From connelly.bill from gmail.com Fri Jun 6 02:44:34 2008 From: connelly.bill from gmail.com (Bill) Date: Fri Jun 6 07:07:15 2008 Subject: [Neuroscience] Relationship between current and voltage in an RC circuit Message-ID: <05b7bbfd-5571-49d1-82dd-d6098d59bbfa@c19g2000prf.googlegroups.com> Hi, I know I'm being dumb here but I can't figure out the relationship between the voltage generated over a cell membrane and current injected into it. I understand it for a simple square step, but for a more complex current function, what is the relationship? From connelly.bill from gmail.com Fri Jun 6 04:34:56 2008 From: connelly.bill from gmail.com (Bill) Date: Fri Jun 6 07:07:37 2008 Subject: [Neuroscience] Re: Relationship between current and voltage in an RC circuit References: <05b7bbfd-5571-49d1-82dd-d6098d59bbfa@c19g2000prf.googlegroups.com> Message-ID: Don't worry I've figured it out. I was confused because intuitively I could see that the relationship was going to be something like dV/dt = I/C but I was confused because that would imply that after the current was turned off, the membrane voltage would stay perturbed by the current, i.e. it would settle back down to zero. However I had of course forgotten about the 'leak' conductances so its more like dV/dt = I(excite)/C - I(leak)/C and of course, thoses Is would be better replaced with g(V-E). On Jun 6, 7:44 pm, Bill wrote: > Hi, > > I know I'm being dumb here but I can't figure out the relationship > between the voltage generated over a cell membrane and current > injected into it. I understand it for a simple square step, but for a > more complex current function, what is the relationship? From tehgabriel from web.de Fri Jun 6 08:50:17 2008 From: tehgabriel from web.de (Tom) Date: Fri Jun 6 11:45:32 2008 Subject: [Neuroscience] Alternative software for a "Coolsnap HQ" camera Message-ID: <3cdf9fe7-d04d-4549-b1e1-6a752f04243c@y21g2000hsf.googlegroups.com> Hi! I have a 'Coolsnap HQ' from Princeton that came together with a software package called "WinView". Unfortunately this software is full of bugs and really a pain to use. So i am wondering if anybody knows an image acquisition software that can be used to control a 'Coolsnap HQ' camera? If possible, this software should run under linux, but windows is fine too. It should allow high frequency imaging (up to 20 Hz), where the timing is triggered by an external device. I already tried a software called "micro-manager" but didn't find this suitable for my needs Any comments are appreciated! Regards, Thomas From paradox137 from teranews.com Fri Jun 6 14:09:03 2008 From: paradox137 from teranews.com (paradox137) Date: Fri Jun 6 14:59:17 2008 Subject: [Neuroscience] neuron numbers? In-Reply-To: <3cdf9fe7-d04d-4549-b1e1-6a752f04243c@y21g2000hsf.googlegroups.com> References: <3cdf9fe7-d04d-4549-b1e1-6a752f04243c@y21g2000hsf.googlegroups.com> Message-ID: <5fd3b$48498b5c$15739@news.teranews.com> Leads to the following topics appreciated: One of my particular interests is the "neuron numbers" in specific brain nuclei. Also, the various in-utero timings for the establishing of nuclei-specific neuron numbers, which can be related to gender. Also, eventually, the co-factors which can be naturally modulated so as to render atypical the organism's developmental determining of neuron numbers. ** Posted from http://www.teranews.com ** From tehgabriel from web.de Mon Jun 9 04:55:31 2008 From: tehgabriel from web.de (Tom) Date: Mon Jun 9 11:33:26 2008 Subject: [Neuroscience] Re: neuron numbers? References: <3cdf9fe7-d04d-4549-b1e1-6a752f04243c@y21g2000hsf.googlegroups.com> <5fd3b$48498b5c$15739@news.teranews.com> Message-ID: <54508d8e-d7de-431c-a31c-314ac21d7663@d1g2000hsg.googlegroups.com> Thanks! A really helpful answer. From tehgabriel from web.de Mon Jun 9 04:56:47 2008 From: tehgabriel from web.de (Tom) Date: Mon Jun 9 11:33:33 2008 Subject: [Neuroscience] Technical question: Alternative software for a "Coolsnap HQ" camera Message-ID: <4d10d8e2-632f-4066-ab3a-901261f5e956@k30g2000hse.googlegroups.com> Hi! I have a 'Coolsnap HQ' from Princeton that came together with a software package called "WinView". Unfortunately this software is full of bugs and really a pain to use. So i am wondering if anybody knows an image acquisition software that can be used to control a 'Coolsnap HQ' camera? If possible, this software should run under linux, but windows is fine too. It should allow high frequency imaging (up to 20 Hz), where the timing is triggered by an external device. I already tried a software called "micro-manager" but didn't find this suitable for my needs Any comments are appreciated! Regards, Thomas From blueocean12 from tom.com Wed Jun 11 14:36:59 2008 From: blueocean12 from tom.com (blueocean12@tom.com) Date: Wed Jun 11 19:18:37 2008 Subject: [Neuroscience] Long-term potentiation and depression Message-ID: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> Hi, I am confused about the LTP, LTD things. Are LTP and LTD only expressed at excitatory synapse? Why people often include bicuculline in their eternal solution during recording? How long the potentiation should last we can call it long-term potentiation contrast to short- term plasticity. Thanks! From usenet02 from out-of-phase.de Thu Jun 12 09:24:29 2008 From: usenet02 from out-of-phase.de (Christian Wilms) Date: Thu Jun 12 10:01:00 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> Message-ID: <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> Hi, you are understandably confused. Long-term plasticity is a vast field, which has so far evaded any attempt to sort things. You might want to have a look at the following papers for a humorous look at the field: J. Sanes and J. Lichtmann. Can molecules explain long-term potentiation. Nature Neuroscience, 2:597-604, 1999. S. J. Lisman J, Lichtman JW. Ltp: perils and progress. Nature Reviews Neuroscience, 4, 2003. Now to your questions. LTP and LTD are expressed in both excitatory and inhibitory synapses. While initial studies focused only on excitatory synapses, inhibitory synapses are coming more and more into focus. Researchers add bicuculline to the external solution as they want to be able to stimulate excitatory inputs to the cell they are recording from, without stimulating inhibitory inputs. I think in general short-term plasticity refers to changes lasting seconds and minutes, while long-term refers to changes lasting hours (though 30 minutes is commonly considered to be long-enough-term for experimental purposes ;) Hope that helps for starters, Christian From decoy from mindyaown.biz Thu Jun 12 20:24:40 2008 From: decoy from mindyaown.biz (Entertained by my own EIMC) Date: Fri Jun 13 11:03:02 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> Message-ID: <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> "Christian Wilms" wrote in message news:1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de... > I think in general short-term plasticity refers to changes lasting > seconds and minutes, while long-term refers to changes lasting hours > (though 30 minutes is commonly considered to be long-enough-term for > experimental purposes ;) That a brainscientist (presumably) can be so narrow-minded as to limit his definition of LTP to "hours" is *almost* unbelievable, to me. From r_s_norman from _comcast.net Thu Jun 12 20:50:04 2008 From: r_s_norman from _comcast.net (r norman) Date: Fri Jun 13 11:03:14 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> Message-ID: <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> On Fri, 13 Jun 2008 11:24:40 +1000, "Entertained by my own EIMC" wrote: >"Christian Wilms" wrote in message >news:1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de... > >> I think in general short-term plasticity refers to changes lasting >> seconds and minutes, while long-term refers to changes lasting hours >> (though 30 minutes is commonly considered to be long-enough-term for >> experimental purposes ;) > >That a brainscientist (presumably) can be so narrow-minded as to limit his >definition of LTP to "hours" is *almost* unbelievable, to me. > What is unbelievable? I understood "hours" to mean "hours or more". From decoy from mindyaown.biz Thu Jun 12 22:21:38 2008 From: decoy from mindyaown.biz (Entertained by my own EIMC) Date: Fri Jun 13 11:03:19 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> Message-ID: <4851e7ba$0$12978$5a62ac22@per-qv1-newsreader-01.iinet.net.au> "Entertained by my own EIMC" wrote in message news:4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au... > "Christian Wilms" wrote in message > news:1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de... > >> I think in general short-term plasticity refers to changes lasting >> seconds and minutes, while long-term refers to changes lasting hours >> (though 30 minutes is commonly considered to be long-enough-term for >> experimental purposes ;) > > That a brainscientist (presumably) can be so narrow-minded as to limit his > definition of LTP to "hours" is *almost* unbelievable, to me. > What made me react - a bit too rapidly - was this (interest and concern of mine): The *truly long-term* consequences of LTP (and the kinds of learning or conditioning that it allows) do obviously underpin the insidious dynamic neural states ("primal pain" or CURSES) that drive *not just* symptoms that are so easily recognized as being caused by a conditioned-in aftereffect of some specific predicament that a person has been (is no longer) in, that they have come to be called "PTSD(s)" *but do also* underpin symptoms of anything from the most sophisticated adaptive (in some cases not just socially accepted but idolized) forms of 'AE_VASIVE ("Ambiadvantageously Evolved" and learned/developed) behavior' [or more conventionally, but less precisely, put: "successful neurotic defenses"] to the most bizarre and antisocial symptoms of overloaded and broken-down neural means of coping with CURSES. [It is highly unrealistic to expect that primal pain (or CURSES) can be cleanly or neutrally contained within a brain. Instead, on fundamental evolutionary ('naturally selective') and neurophysiological grounds, potentially self-defeating pain/fear/distress-motivating excitatory signals are inevitably not just getting blocked (or "gated") but also tending to get *rerouted* to co-motivate much of people's focusing (paying) of more or less adaptive "actentions" {"actention"=either or both visceromotor, 'sceletomotor', and "mental" (intellectual or cognitive) activities - or ditto preoccupations}.] From decoy from mindyaown.biz Thu Jun 12 22:40:52 2008 From: decoy from mindyaown.biz (Entertained by my own EIMC) Date: Fri Jun 13 11:03:24 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> Message-ID: <4851ec3b$0$12992$5a62ac22@per-qv1-newsreader-01.iinet.net.au> "r norman" wrote in message news:9hk3541so7j4teh5f252hmo27colba36gt@4ax.com... > On Fri, 13 Jun 2008 11:24:40 +1000, "Entertained by my own EIMC" > wrote: > >>"Christian Wilms" wrote in message >>news:1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de... >> >>> I think in general short-term plasticity refers to changes lasting >>> seconds and minutes, while long-term refers to changes lasting hours >>> (though 30 minutes is commonly considered to be long-enough-term for >>> experimental purposes ;) >> >>That a brainscientist (presumably) can be so narrow-minded as to limit his >>definition of LTP to "hours" is *almost* unbelievable, to me. >> > > What is unbelievable? I understood "hours" to mean "hours or more". I think hours - e.g. from 2 - 24 for all I care - of LTP might be enough to cause life-long changes of some excitatory and inhibitory interneurons. I understand how - but I still find it hard to take *that* - so many people (especially people who purport, or whose job it is to try, to understand 'how we tick') don't see much beyond a narrow (too narrow) field of interest. From r_s_norman from _comcast.net Fri Jun 13 08:05:35 2008 From: r_s_norman from _comcast.net (r norman) Date: Fri Jun 13 11:03:29 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> <4851ec3b$0$12992$5a62ac22@per-qv1-newsreader-01.iinet.net.au> Message-ID: On Fri, 13 Jun 2008 13:40:52 +1000, "Entertained by my own EIMC" wrote: > >"r norman" wrote in message >news:9hk3541so7j4teh5f252hmo27colba36gt@4ax.com... >> On Fri, 13 Jun 2008 11:24:40 +1000, "Entertained by my own EIMC" >> wrote: >> >>>"Christian Wilms" wrote in message >>>news:1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de... >>> >>>> I think in general short-term plasticity refers to changes lasting >>>> seconds and minutes, while long-term refers to changes lasting hours >>>> (though 30 minutes is commonly considered to be long-enough-term for >>>> experimental purposes ;) >>> >>>That a brainscientist (presumably) can be so narrow-minded as to limit his >>>definition of LTP to "hours" is *almost* unbelievable, to me. >>> >> >> What is unbelievable? I understood "hours" to mean "hours or more". > >I think hours - e.g. from 2 - 24 for all I care - of LTP might be enough to >cause life-long changes of some excitatory and inhibitory interneurons. > >I understand how - but I still find it hard to take *that* - so many people >(especially people who purport, or whose job it is to try, to understand >'how we tick') don't see much beyond a narrow (too narrow) field of >interest. > I still don't understand your problem. Neurobiologists have no difficulty at all understanding that memory and learning can last a lifetime. It is just that there is a whole array of changes caused by experience within neurobiology, all produced by different mechanisms, some lasting milliseconds, some lasting seconds or minutes or hours. And some are permanent. There do seem to be connections between long-term potentiation and permanent memory but permanence is almost certain to involve still other mechanisms at work than those that ultimately fade away. From tehgabriel from web.de Fri Jun 13 09:47:50 2008 From: tehgabriel from web.de (Tom) Date: Fri Jun 13 11:03:34 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> <4851ec3b$0$12992$5a62ac22@per-qv1-newsreader-01.iinet.net.au> Message-ID: <8196500b-1cec-40ad-82b2-8f759bb93f8e@a1g2000hsb.googlegroups.com> Hi, i think Christian already gave a nice summary. I'd like to add that LTP/LTD has basically nothing to do with short-term-plasticity (STP). The first describing the change of synaptiv weights/efficiancy as result corelated activity in both presynaptic and postsynaptic neuron. The latter rather summarizes (mainly) presynaptic effects like vesicle pool depletion, change of poolsize etc. Whereas LTP/LTD are commonly associated with learning, STP seems to be important for shaping activity patterns within spike trains. From usenet02 from out-of-phase.de Fri Jun 13 10:02:37 2008 From: usenet02 from out-of-phase.de (Christian Wilms) Date: Fri Jun 13 11:03:43 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> Message-ID: <1iihdrs.1px8y3v1fwmyf4N%usenet02@out-of-phase.de> r norman wrote: > What is unbelievable? I understood "hours" to mean "hours or more". That was what I meant. I had initially thought that would be clear. Well, proved wrong again ;) Chris From decoy from mindyaown.biz Fri Jun 13 20:53:03 2008 From: decoy from mindyaown.biz (Entertained by my own EIMC) Date: Sat Jun 14 12:14:29 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> <1iihdrs.1px8y3v1fwmyf4N%usenet02@out-of-phase.de> Message-ID: <48532472$0$12975$5a62ac22@per-qv1-newsreader-01.iinet.net.au> "Christian Wilms" wrote in message news:1iihdrs.1px8y3v1fwmyf4N%usenet02@out-of-phase.de... >r norman wrote: > >> What is unbelievable? I understood "hours" to mean "hours or more". > That was what I meant. I had initially thought that would be clear. > Well, proved wrong again ;) > > Chris Yes, when "hours" is meant to imply "a lifetime" it takes just a second for someone like me to misinterpret the minutiae of this meaning. I wish people were as accomodating with my definitional deficiencies. ;-> From connelly.bill from gmail.com Fri Jun 13 22:23:47 2008 From: connelly.bill from gmail.com (Bill) Date: Sat Jun 14 12:14:33 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> Message-ID: People often put bicucculine in the mix because if you're having trouble getting LTP (ot at least maintaining it), you put a GABA(A) blocker in the mix and you often get it. On Jun 13, 2:24 am, usene...@out-of-phase.de (Christian Wilms) wrote: > Hi, > > you are understandably confused. Long-term plasticity is a vast field, > which has so far evaded any attempt to sort things. You might want to > have a look at the following papers for a humorous look at the field: > > J. Sanes and J. Lichtmann. Can molecules explain long-term potentiation. > Nature Neuroscience, 2:597-604, 1999. > > S. J. Lisman J, Lichtman JW. Ltp: perils and progress. Nature Reviews > Neuroscience, 4, 2003. > > Now to your questions. LTP and LTD are expressed in both excitatory and > inhibitory synapses. While initial studies focused only on excitatory > synapses, inhibitory synapses are coming more and more into focus. > > Researchers add bicuculline to the external solution as they want to be > able to stimulate excitatory inputs to the cell they are recording from, > without stimulating inhibitory inputs. > > I think in general short-term plasticity refers to changes lasting > seconds and minutes, while long-term refers to changes lasting hours > (though 30 minutes is commonly considered to be long-enough-term for > experimental purposes ;) > > Hope that helps for starters, > > Christian From usenet02 from out-of-phase.de Sat Jun 14 07:35:15 2008 From: usenet02 from out-of-phase.de (Christian Wilms) Date: Sat Jun 14 12:14:38 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> <1iihdrs.1px8y3v1fwmyf4N%usenet02@out-of-phase.de> <48532472$0$12975$5a62ac22@per-qv1-newsreader-01.iinet.net.au> Message-ID: <1iij1kl.8a7xcz10ggndiN%usenet02@out-of-phase.de> Entertained by my own EIMC wrote: > Yes, when "hours" is meant to imply "a lifetime" it takes just a second > for someone like me to misinterpret the minutiae of this meaning. I would be willing to bet against "a lifetime" when it comes to classic LTP/LTD. I think long-term "storage" will prove to be mediated by a different mechanism. Best, Chris From usenet02 from out-of-phase.de Sat Jun 14 07:35:15 2008 From: usenet02 from out-of-phase.de (Christian Wilms) Date: Sat Jun 14 12:14:43 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> Message-ID: <1iij1o0.1c71ezk7s4vetN%usenet02@out-of-phase.de> Bill wrote: > People often put bicucculine in the mix because if you're having > trouble getting LTP (ot at least maintaining it), you put a GABA(A) > blocker in the mix and you often get it. Wouldn't that imply that one is stimulating inhibitory input as well and thus possibly not only inducing plasticity in the excitatory path, but also in the inhibitory path. That would do quite a good job at complicating the results. Best, Chris From connelly.bill from gmail.com Sat Jun 14 18:05:09 2008 From: connelly.bill from gmail.com (Bill) Date: Sun Jun 15 11:56:35 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> <1iihdrs.1px8y3v1fwmyf4N%usenet02@out-of-phase.de> <48532472$0$12975$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <1iij1kl.8a7xcz10ggndiN%usenet02@out-of-phase.de> Message-ID: <1653872d-fef6-4dcc-b46c-d6a088f73d11@w8g2000prd.googlegroups.com> On Jun 15, 12:35 am, usene...@out-of-phase.de (Christian Wilms) wrote: > Entertained by my own EIMC wrote: > > > Yes, when "hours" is meant to imply "a lifetime" it takes just a second > > for someone like me to misinterpret the minutiae of this meaning. > > I would be willing to bet against "a lifetime" when it comes to classic > LTP/LTD. I think long-term "storage" will prove to be mediated by a > different mechanism. > > Best, Chris Well there is LTP and there is LTP like mechanisms. Nothing in the brain is done by LTP (100Hz for 1 sec 3 times). However strong depolarisation leading to NMDA receptor dependent enhancement of synaptic strength, I would be willing to bet that memory formation, and maintainance is deeply dependent on this kind of mechanisms. (Re: How long does LTP last, at least a year in an Adult Rat Perforant path- DG (Abraham WC. How long will long-term potentiation last? Philos Trans R Soc Lond B Biol Sci. 2003 358(1432):735-44) From connelly.bill from gmail.com Sat Jun 14 18:13:37 2008 From: connelly.bill from gmail.com (Bill) Date: Sun Jun 15 11:56:41 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <1iij1o0.1c71ezk7s4vetN%usenet02@out-of-phase.de> Message-ID: On Jun 15, 12:35 am, usene...@out-of-phase.de (Christian Wilms) wrote: > Bill wrote: > > People often put bicucculine in the mix because if you're having > > trouble getting LTP (ot at least maintaining it), you put a GABA(A) > > blocker in the mix and you often get it. > > Wouldn't that imply that one is stimulating inhibitory input as well and > thus possibly not only inducing plasticity in the excitatory path, but > also in the inhibitory path. That would do quite a good job at > complicating the results. > > Best, Chris Well I don't think there is any doubt that field stimulation in the hippocampus recruits (often powerful) inhibition, whether directly or or via the local circuit. I get your meaning, but I definately know of LTP researchers who think adding a GABA(A) antagonist is cheating. When you're looking at field EPSPs GABAergic inhibtion has almost no impact on the size or kinetics of the event, so you are essentially looking at a selective glutamatergic event. (While of course I appreciate GABA will be having large impacts of the integration of said EPSP). With field stimulation, in the presence of of GABA blockade, you often get epileptiform activity, so you're confounding things that way as well. If you were looking at spike timing dependent plasticity, and were only recruiting a single axon, then you'd be fine in blocking GABA, as your source of (back propagating) AP formation is your current injection. But if you're hoping to recruit the APs with field stimulation, then GABA(A) blockade is going to be doing some odd stuff. From connelly.bill from gmail.com Sat Jun 14 18:20:00 2008 From: connelly.bill from gmail.com (Bill) Date: Sun Jun 15 11:56:48 2008 Subject: [Neuroscience] Horse Radish Peroxidase -DAB Reaction Message-ID: Hi, Does the chromogenic reaction of HRP with DAB actually require H2O2 at the same time? That is to say, in an isolated system (with no endogenous peroxisdases to complicate things), does HRP + DAB = BROWN require H2O2? If so, how is that reaction actually happening, i.e. what is being released or consumed by the HRP such that DAB reacts? Thanks From r_s_norman from _comcast.net Sat Jun 14 18:20:07 2008 From: r_s_norman from _comcast.net (r norman) Date: Sun Jun 15 11:56:55 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> <1iihdrs.1px8y3v1fwmyf4N%usenet02@out-of-phase.de> <48532472$0$12975$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <1iij1kl.8a7xcz10ggndiN%usenet02@out-of-phase.de> <1653872d-fef6-4dcc-b46c-d6a088f73d11@w8g2000prd.googlegroups.com> Message-ID: On Sat, 14 Jun 2008 16:05:09 -0700 (PDT), Bill wrote: >On Jun 15, 12:35 am, usene...@out-of-phase.de (Christian Wilms) wrote: >> Entertained by my own EIMC wrote: >> >> > Yes, when "hours" is meant to imply "a lifetime" it takes just a second >> > for someone like me to misinterpret the minutiae of this meaning. >> >> I would be willing to bet against "a lifetime" when it comes to classic >> LTP/LTD. I think long-term "storage" will prove to be mediated by a >> different mechanism. >> >> Best, Chris > >Well there is LTP and there is LTP like mechanisms. Nothing in the >brain is done by LTP (100Hz for 1 sec 3 times). However strong >depolarisation leading to NMDA receptor dependent enhancement of >synaptic strength, I would be willing to bet that memory formation, >and maintainance is deeply dependent on this kind of mechanisms. (Re: >How long does LTP last, at least a year in an Adult Rat Perforant path- >DG (Abraham WC. How long will long-term potentiation last? Philos >Trans R Soc Lond B Biol Sci. 2003 358(1432):735-44) Once you start a second messenger cell signaling pathway, what you call a "different" mechanism becomes much a matter of philosophy. If you temporarily upregulate a synaptic receptor pathway so that the effect lasts hours or days until protein turnover restores it to the old value, is that a different mechanism from one that activates a different kind of gene switch that can last forever but still uses a number of the same intermediaries? I would call these different. From connelly.bill from gmail.com Sat Jun 14 20:30:37 2008 From: connelly.bill from gmail.com (Bill) Date: Sun Jun 15 11:57:00 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> <1iihdrs.1px8y3v1fwmyf4N%usenet02@out-of-phase.de> <48532472$0$12975$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <1iij1kl.8a7xcz10ggndiN%usenet02@out-of-phase.de> <1653872d-fef6-4dcc-b46c-d6a088f73d11@w8g2000prd.googlegroups.com> Message-ID: <5ccc1238-fba5-45a1-a6bb-88497c9dcf53@q27g2000prf.googlegroups.com> Hm, I suppose you're right. Initially I wrote this post disagreeing with you, but as I explored the following analogy, I changed my mind to a degree. Would you say, that the people in Hiroshima who were vaporised directly by the high density of photons, and those that died six weeks later from radiation poisoning were killed by the same mechanism. You could argue that they were (the mechanism being a nuclear explosion) or you could argue that they weren't. I thought you were meaning that while an NMDA-R dependent mechanism causes an initial change in synaptic weights in the hippocampus/MTL sturctures, but the distribution of the engram throughout the cortex require something completely different. On Jun 15, 11:20 am, r norman wrote: > > Once you start a second messenger cell signaling pathway, what you > call a "different" mechanism becomes much a matter of philosophy. If > you temporarily upregulate a synaptic receptor pathway so that the > effect lasts hours or days until protein turnover restores it to the > old value, is that a different mechanism from one that activates a > different kind of gene switch that can last forever but still uses a > number of the same intermediaries? I would call these different. From connelly.bill from gmail.com Sat Jun 14 20:36:59 2008 From: connelly.bill from gmail.com (Bill) Date: Sun Jun 15 11:57:05 2008 Subject: [Neuroscience] Re: Horse Radish Peroxidase -DAB Reaction References: Message-ID: <6caa8880-070a-48cc-9516-e917632e2e2d@w34g2000prm.googlegroups.com> Don't worry. I found the answer. H2O2 reacts, which releases O2, which reacts with the DAB. On Jun 15, 11:20 am, Bill wrote: > Hi, > > Does the chromogenic reaction of HRP with DAB actually require H2O2 at > the same time? That is to say, in an isolated system (with no > endogenous peroxisdases to complicate things), does HRP + DAB = BROWN > require H2O2? If so, how is that reaction actually happening, i.e. > what is being released or consumed by the HRP such that DAB reacts? > > Thanks From r_s_norman from _comcast.net Sun Jun 15 09:00:34 2008 From: r_s_norman from _comcast.net (r norman) Date: Sun Jun 15 11:57:17 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> <1iihdrs.1px8y3v1fwmyf4N%usenet02@out-of-phase.de> <48532472$0$12975$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <1iij1kl.8a7xcz10ggndiN%usenet02@out-of-phase.de> <1653872d-fef6-4dcc-b46c-d6a088f73d11@w8g2000prd.googlegroups.com> <5ccc1238-fba5-45a1-a6bb-88497c9dcf53@q27g2000prf.googlegroups.com> Message-ID: On Sat, 14 Jun 2008 18:30:37 -0700 (PDT), Bill wrote: > >On Jun 15, 11:20 am, r norman wrote: >> >> Once you start a second messenger cell signaling pathway, what you >> call a "different" mechanism becomes much a matter of philosophy. If >> you temporarily upregulate a synaptic receptor pathway so that the >> effect lasts hours or days until protein turnover restores it to the >> old value, is that a different mechanism from one that activates a >> different kind of gene switch that can last forever but still uses a >> number of the same intermediaries? I would call these different. >Hm, I suppose you're right. Initially I wrote this post disagreeing >with you, but as I explored the following analogy, I changed my mind >to a degree. Would you say, that the people in Hiroshima who were >vaporised directly by the high density of photons, and those that died >six weeks later from radiation poisoning were killed by the same >mechanism. You could argue that they were (the mechanism being a >nuclear explosion) or you could argue that they weren't. > >I thought you were meaning that while an NMDA-R dependent mechanism >causes an initial change in synaptic weights in the hippocampus/MTL >sturctures, but the distribution of the engram throughout the cortex >require something completely different. OK, to be more specific: I would look more at the way that last, key step works than at the route taken. So if several routes all ultimately increase the number of post-synaptic receptors at a site then they are the "same" mechanism at least in so far as the result of increasing synaptic efficacy. However, changing the specific molecular form of a receptor while also building in number is a different mechanism, as is adding any other synaptic structure or building the size of the synapse even though the number of receptors is still increased. I still think that what we ordinarily call permanent "learning" or "memory" differs in mechanism in this sense than the factors that cause the long term potentiation that lasts hours and days. From decoy from mindyaown.biz Wed Jun 18 03:25:39 2008 From: decoy from mindyaown.biz (Entertained by my own EIMC) Date: Wed Jun 18 11:38:06 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> <1iihdrs.1px8y3v1fwmyf4N%usenet02@out-of-phase.de> <48532472$0$12975$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <1iij1kl.8a7xcz10ggndiN%usenet02@out-of-phase.de> <1653872d-fef6-4dcc-b46c-d6a088f73d11@w8g2000prd.googlegroups.com> Message-ID: <4858c683$0$11607$5a62ac22@per-qv1-newsreader-01.iinet.net.au> "r norman" wrote in message news:eak8545lshq32jothp7uee7abeuccv6l8c@4ax.com... > On Sat, 14 Jun 2008 16:05:09 -0700 (PDT), Bill > wrote: > >>On Jun 15, 12:35 am, usene...@out-of-phase.de (Christian Wilms) wrote: >>> Entertained by my own EIMC wrote: >>> >>> > Yes, when "hours" is meant to imply "a lifetime" it takes just a >>> > second >>> > for someone like me to misinterpret the minutiae of this meaning. >>> >>> I would be willing to bet against "a lifetime" when it comes to classic >>> LTP/LTD. I think long-term "storage" will prove to be mediated by a >>> different mechanism. >>> >>> Best, Chris >> >>Well there is LTP and there is LTP like mechanisms. Nothing in the >>brain is done by LTP (100Hz for 1 sec 3 times). However strong >>depolarisation leading to NMDA receptor dependent enhancement of >>synaptic strength, I would be willing to bet that memory formation, >>and maintainance is deeply dependent on this kind of mechanisms. (Re: >>How long does LTP last, at least a year in an Adult Rat Perforant path- >>DG (Abraham WC. How long will long-term potentiation last? Philos >>Trans R Soc Lond B Biol Sci. 2003 358(1432):735-44) > > Once you start a second messenger cell signaling pathway, what you > call a "different" mechanism becomes much a matter of philosophy. If > you temporarily upregulate a synaptic receptor pathway so that the > effect lasts hours or days until protein turnover restores it to the > old value, is that a different mechanism from one that activates a > different kind of gene switch that can last forever but still uses a > number of the same intermediaries? I would call these different. > It will is of course always be possible to "split hairs". %} The possibility (to split hairs) does not change the fact that there are precise changes within brains (changes that are not perfectly specified, or defined, nor necessarily ever perfectly specifiable) that LTP is a (far from 'inEPT') explanatory pointer toward. These are not uncommon changes, And, why and how they occur, and *that* they have consequences that are deeply ironic (and far from completely comedic). I don't know of a careful and conventional science-reflecting expression that is better than LTP (though it is of course even better if supplemented by references to all relevant forms of "neural plasticity") at serving the purpose of referring to how excitatory and inhibitory neurons [that most centrally and directly maintain the kind of states that I call CURSES - a concept (concEPT) that Janov calls primal pain and that the commercially and legally clever originators of a sect that calls itself The Church of Scientology euphemistically refer to as "engrams" and that 'mainstream followers of Freud' would tend to describe something like "repressed memories imprinted by traumatizing predicaments"] can and do get 'conditioned' (i.e. CURSES-specific neurons can/do get 'functurally' altered) by predicaments of a type that "implores" (a figurative stand-in for "requires" - i.e., requires for reproductive and/or individual survival) "_specific/synaptic hibernation_". "Specific/synaptic hibernation" is part of a fresh (by me found and funnily formulated) way of perceiving and poignantly pointing out that, why, and how we function and have evolved to have the capacity to function, and normally develop (and tend to be environmentally conditioned) to function, in ways that contain CURSES; That is, contain and often allows creative coping with CURSES type states after these have been 'created' (or as if 'put') inside people's central nervous {and "actention selection serving"} systems by predicaments that by definitely *not* inEPT definition "implore Specific/synaptic Hibernation". Specific/synaptic hibernation is to be understood against the contrasting background of "general hibernation" (or aestivation, for the fact that an important part of the common functional character of general and specific hibernation is, that any 'default response' (that is, the response that would occur in the absence of a capacity to cope by way of either specific hibernation or general hibernation) would _not_ essentially involve a self-regulatory function that achieves either a highly specific (post-synaptic) or general (affecting the entire inividual organism) state of "muted" (or minimized) metabolism. Human individuals (especially immature ones that are dependent on parents or others for having their needs met - but of course other animals too) can significantly often be found to be in anything from very slowly to very rapidly occurred natural or 'socially natural' predicament (or ordeal) that can be referred to as "SHI (by approximate and MAD-inspired abbrevation from Specific/synaptic Hibernation Imploring) type situations". N.B.: Replacing the figurative word "imploring" with "inducing" would immediately collapse the completely generic quality of this concEPT/definition! The consequences of SHI-type situations come CURSES are ironic in the sense that they cause people [not the least those that are dedicated to (and/or professionally preoccupied with) trying to understand our own brains and behavior] to be selectively unconscious. However, as it is can be encompassingly explained in an in-dEPTh (or in the one and only EPT) way, this kind of automatic defensive psychophysiological adjustment to inescapable adversity does often have a spin-off in that the LTP'ed excitatory component of the corresponding CURSES come to be channelled (or "rerouted") into and play a co-motivating part in people's learning of procreation promoting or [IOW, and in the context of conceivable, realistic, and relevant examples of "the naturally selective/Evolutionary Pressure Totality"] _"opportune" or 'opportunity-taking ways of paying/focusing "actention". This thus "double-edged" (obviously-to-have-been-naturally-selected-for) coping capability can be referred to (using pragmatically loose grammar and strategically smudged sem_antics) as "AEVASIVE" adjustments/adaptations/behaviors (etc). Hence, it follows from EPT logic ;) that people who in their most vulnerable and formative stage of life were challanged by SHI-type predicaments (or ordeals) that turned into "selective hibernation _inducing_" type situations and CURSES in general (with very few excEPTions ;)) tend to be selectively incapable of percEPTivity and of coming to conceptual - even less often concEPTual - grips with) this very aspect of What Is (what has, is, and will be) going on. The irony of this aspect is what I have ironed-out by help of an approach that combines perverse percEPTivity with science-aligned 'fuzz_silly' logic" (EPTly so to speak). Or, as it can be expressed by help of a more frivolous (but still only decEPTively nothing but silly) MAD-inspired encoding: I ironed-out this by me originally only intuitively and eventually too irritatingly understood aspect by way of error plagued trials of a 'S_EPT_IC humored' analytical approach. Mind you, this my pursuit and preoccupation has been no less AEVASIVE and no less originally co-motivated by SHI-type predicaments and subsequently crucially co-motivated by CURSES than different other AEVASIVE pursuits or preoccupations by others. However, mine has most definitely been 'more EPT' than any other AEVASIVE historical and prehistorical human endeavor! ;-) My regards to whoever tried to read and could stomach this reply P -- P.S. The meaning of the acronym AEVASIVE makes the meaning of "AEVASIVE endeavors" (or ditto preoccupations) not merely approximately synonymous with but far more in-depth, objective, and balanced than the meaning of: "endeavors [or preoccupations or pursuits] that nearly in every individual and collective case symptomatic of "neurotic defenses" at work". From wwt0657 from gmail.com Wed Jun 18 19:47:38 2008 From: wwt0657 from gmail.com (wwt) Date: Thu Jun 19 11:39:28 2008 Subject: [Neuroscience] question of inferior olive slice Message-ID: <5d4fe632-7607-4241-a86d-ec762c6d2f34@j33g2000pri.googlegroups.com> Hi! everyone. Recently, I was cutting inferior olive sagittal slice in rats (about 20d, female and male) and doing patch on these. Unfortunately, the health of slice always was too bad. As you know, the inferior olive is at very superficial position of ventral brain stem. When I extract the brain stem, I feel it is too difficult to avoid hurting the inferior olive. And there is a layer of meninge adhering on the surface of inferior olive. It is almost impossible to cut off meninges clearly in 20d rats during my operation. So the brain stem is always extruded during cutting process. But if I clean the meninges before cutting, it is ease to drag the tissue, even operation carefully. How can I do for avoiding these? Yosi Yarom's Research Lab use sucrose ACSF to cut inferior olive slice. The concentration of sucrose is about 124mM in their cutting solution( for example: J Neurophysiol 85:1686-1696, 2001. http://jn.physiology.org/cgi/content/full/85/4/1686#BIBL). And there are no NaCl in cutting solution. But this solution is a kind of low osmotic pressure, about 220 mOsm. I feel it is strange. Do you know the principle or reason of it? From connelly.bill from gmail.com Mon Jun 23 18:41:29 2008 From: connelly.bill from gmail.com (Bill) Date: Mon Jun 23 22:39:10 2008 Subject: [Neuroscience] Re: question of inferior olive slice References: <5d4fe632-7607-4241-a86d-ec762c6d2f34@j33g2000pri.googlegroups.com> Message-ID: <26c41702-f2cc-44e5-af44-0f120e564339@z16g2000prn.googlegroups.com> The principle behind the sucrose solution is simple. During strong insults to the brain, depolarization causes Cl- influx which eventually bursts the cell due to osmotic pressure. Further down the track, the calcium influx causes by the depolarization has activated cell death pathways. By removing Na+ and Cl- from the solution, you stop any depolarization and you stop and Cl- influx respectively. You can actually use a low sodium solution (Like Choline Cl-) because without the Na+ you can't get the depolarization in the first place. But weighing out sucrose is more pleasant than choline chloride. See the original paper on Sucrose by George Aghajanian, where it was developed for making slices of the facial nuclei (not too far from where you are working) Aghajanian GK, Rasmussen K. Intracellular studies in the facial nucleus illustrating a simple new method for obtaining viable motoneurons in adult rat brain slices. Synapse. 1989;3(4):331-8 I think who ever said they used 124mM sucrose made a mistake (I hope they did at least), you need to double the sucrose relative to NaCl... The solution I use is 248 sucrose, 3 KCl, 2 MgCl2, 1 CaCl2, 1.25 NaH2PO4, 26 NaHCO3, and 10 D-glucose. Some people use 10mM Mg2+ and 0.1mM Ca2+ but I never found it made a difference. I strongly recommend the sucrose solution, I expect you will find a vast improvement in your slices (where ever you cut your slices from in fact). I also recommend incubating your slices at 35 degrees for half an hour to an hour after slicing. Another thing which I have found enhances the viability of some neurons is adding 1mM Na Ascorbate and 3mM Pyruvate (makes CA3 pyramidal, dentate granule and cerebellar granule neurons appear more healthy, but seems to have no effect on cortical neurons). Finally, 20 days seems to be getting a little on the old side for such a mylin rich area. When I have worked in those kind of places, 21 days old was my absolute limit for finding viable cells. If at all possible I would work from 17 days old or younger. All of that wont help too much with the problem of minigies. My only advise would be to take your time. With animals of this age, the decapitated brain seems to survive for a long time before you need to cut slices. Get you boss to buy you some ultra fine forceps, some moria spring scissors and a dissecting scope, and make sure you don't have any coffee before the dissection! On Jun 19, 12:47?pm, wwt wrote: > Hi! everyone. Recently, I was cutting inferior olive sagittal slice in > rats (about 20d, female and male) and doing patch on these. > Unfortunately, the health of slice always was too bad. As you know, > the inferior olive is at very superficial position of ventral brain > stem. When I extract the brain stem, I feel it is too difficult to > avoid hurting the inferior olive. And there is a layer of meninge > adhering on the surface of inferior olive. It is almost impossible to > cut off meninges clearly in 20d rats during my operation. So the brain > stem is always extruded during cutting process. But if I clean the > meninges before cutting, it is ease to drag the tissue, even operation > carefully. How can I do for avoiding these? > Yosi Yarom's Research Lab use sucrose ACSF to cut inferior olive > slice. The concentration of sucrose is about 124mM in their cutting > solution( for example: J Neurophysiol 85:1686-1696, 2001.http://jn.physiology.org/cgi/content/full/85/4/1686#BIBL). And there > are no NaCl in cutting solution. But this solution is a kind of low > osmotic pressure, about 220 mOsm. I feel it is strange. Do you know > the principle or reason of it? From connelly.bill from gmail.com Mon Jun 23 23:40:09 2008 From: connelly.bill from gmail.com (Bill) Date: Tue Jun 24 10:31:20 2008 Subject: [Neuroscience] What electrophysiology software are people using? Message-ID: <7968f31c-773e-45cf-8cd6-3a1e7cb83a81@j33g2000pri.googlegroups.com> Hi, I've been trying to find software that is actually functional for the detection and subsequent analysis of spontaneous synaptic events. I've tried using MiniAnalysis, which works, but is very unstable and about as user friendly as a rusting syringe. We acquire data using CEDs spike2, however it is no good for rejecting/accepting events, and it doesn't have the necessary Stats (KS tests). For what ever reason, I can't get WinEDR to open our data, and I can't get "Serf" (http:// www.bram.org/serf/serf.php) to work. Axograph isn't available on PC yet. What is pCLAMP like? Does anyone have any software that they would actually recommend? From connelly.bill from gmail.com Tue Jun 24 00:21:58 2008 From: connelly.bill from gmail.com (Bill) Date: Tue Jun 24 10:31:27 2008 Subject: [Neuroscience] Re: Technical question: Alternative software for a "Coolsnap HQ" camera References: <4d10d8e2-632f-4066-ab3a-901261f5e956@k30g2000hse.googlegroups.com> Message-ID: <8b4acbda-061e-47c6-85a0-d9273a68164e@u12g2000prd.googlegroups.com> I think the Coolsnap cameras can run a large number of programs. NIS elements from nikon, or PMcapture from photometrics, and various others. See: http://www.photomet.com/pm_downloads/software_pvcam.php On Jun 9, 9:56?pm, Tom wrote: > Hi! > I have a 'Coolsnap HQ' from Princeton that came together with a > software package called "WinView". > Unfortunately this software is full of bugs and really a pain to use. > So i am wondering if anybody knows an image acquisition software that > can be used to control a 'Coolsnap HQ' camera? > If possible, this software should run under linux, but windows is fine > too. > > It should allow high frequency imaging (up to 20 Hz), where the timing > is triggered by an external device. > I already tried a software called "micro-manager" but didn't find this > suitable for my needs > > Any comments are appreciated! > > Regards, > Thomas From wwt0657 from gmail.com Tue Jun 24 07:49:03 2008 From: wwt0657 from gmail.com (wwt) Date: Tue Jun 24 10:31:34 2008 Subject: [Neuroscience] Re: question of inferior olive slice References: <5d4fe632-7607-4241-a86d-ec762c6d2f34@j33g2000pri.googlegroups.com> <26c41702-f2cc-44e5-af44-0f120e564339@z16g2000prn.googlegroups.com> Message-ID: <2b055f12-8951-4d2f-a09d-e1f0f6da6aad@p25g2000pri.googlegroups.com> On Jun 24, 7:41?am, Bill wrote: > The principle behind the sucrose solution is simple. During strong > insults to the brain, depolarization causes Cl- influx which > eventually bursts the cell due to osmotic pressure. Further down the > track, the calcium influx causes by the depolarization has activated > cell death pathways. By removing Na+ and Cl- from the solution, you > stop any depolarization and you stop and Cl- influx respectively. You > can actually use a low sodium solution (Like Choline Cl-) because > without the Na+ you can't get the depolarization in the first place. > But weighing out sucrose is more pleasant than choline chloride. > > See the original paper on Sucrose by George Aghajanian, where it was > developed for making slices of the facial nuclei (not too far from > where you are working) > > Aghajanian GK, Rasmussen K. > Intracellular studies in the facial nucleus illustrating a simple new > method for obtaining viable motoneurons in adult rat brain slices. > Synapse. 1989;3(4):331-8 > > I think who ever said they used 124mM sucrose made a mistake (I hope > they did at least), you need to double the sucrose relative to > NaCl... ?The solution I use is 248 sucrose, 3 KCl, 2 MgCl2, 1 CaCl2, > 1.25 NaH2PO4, 26 NaHCO3, and 10 D-glucose. Some people use 10mM Mg2+ > and 0.1mM Ca2+ but I never found it made a difference. > > I strongly recommend the sucrose solution, I expect you will find a > vast improvement in your slices (where ever you cut your slices from > in fact). > > I also recommend incubating your slices at 35 degrees for half an hour > to an hour after slicing. Another thing which I have found enhances > the viability of some neurons is adding 1mM Na Ascorbate and 3mM > Pyruvate (makes CA3 pyramidal, dentate granule and cerebellar granule > neurons appear more healthy, but seems to have no effect on cortical > neurons). > > Finally, 20 days seems to be getting a little on the old side for such > a mylin rich area. When I have worked in those kind of places, 21 days > old was my absolute limit for finding viable cells. If at all possible > I would work from 17 days old or younger. > > All of that wont help too much with the problem of minigies. My only > advise would be to take your time. With animals of this age, the > decapitated brain seems to survive for a long time before you need to > cut slices. Get you boss to buy you some ultra fine forceps, some > moria spring scissors and a dissecting scope, and make sure you don't > have any coffee before the dissection! > > On Jun 19, 12:47?pm, wwt wrote: > > > > > Hi! everyone. Recently, I was cutting inferior olive sagittal slice in > > rats (about 20d, female and male) and doing patch on these. > > Unfortunately, the health of slice always was too bad. As you know, > > the inferior olive is at very superficial position of ventral brain > > stem. When I extract the brain stem, I feel it is too difficult to > > avoid hurting the inferior olive. And there is a layer of meninge > > adhering on the surface of inferior olive. It is almost impossible to > > cut off meninges clearly in 20d rats during my operation. So the brain > > stem is always extruded during cutting process. But if I clean the > > meninges before cutting, it is ease to drag the tissue, even operation > > carefully. How can I do for avoiding these? > > Yosi Yarom's Research Lab use sucrose ACSF to cut inferior olive > > slice. The concentration of sucrose is about 124mM in their cutting > > solution( for example: J Neurophysiol 85:1686-1696, 2001.http://jn.physiology.org/cgi/content/full/85/4/1686#BIBL). And there > > are no NaCl in cutting solution. But this solution is a kind of low > > osmotic pressure, about 220 mOsm. I feel it is strange. Do you know > > the principle or reason of it?- Hide quoted text - > > - Show quoted text - Thank you for your detaily answer. I will try more according your advises. A little question: What is the difference between Na Ascorbate and Ascorbic acid? Can I use Ascorbic acid to replace the role of Na Ascorbate? From wwt0657 from gmail.com Tue Jun 24 08:14:33 2008 From: wwt0657 from gmail.com (wwt) Date: Tue Jun 24 10:31:38 2008 Subject: [Neuroscience] Re: What electrophysiology software are people using? References: <7968f31c-773e-45cf-8cd6-3a1e7cb83a81@j33g2000pri.googlegroups.com> Message-ID: <0baf7495-5207-415d-94e2-4b16891a2f98@z24g2000prf.googlegroups.com> On Jun 24, 12:40?pm, Bill wrote: > Hi, > > I've been trying to find software that is actually functional for the > detection and subsequent analysis of spontaneous synaptic events. I've > tried using MiniAnalysis, which works, but is very unstable and about > as user friendly as a rusting syringe. We acquire data using CEDs > spike2, however it is no good for rejecting/accepting events, and it > doesn't have the necessary Stats (KS tests). For what ever reason, I > can't get WinEDR to open our data, and I can't get "Serf" (http://www.bram.org/serf/serf.php) to work. Axograph isn't available on PC > yet. > > What is pCLAMP like? Does anyone have any software that they would > actually recommend? In our lab, we use pClamp to analyze the electrophysiological data. I know that it have a function named event detection. Our interesting is not on sEPSCs or mEPSCs, so I don't use this function for synaptic works. But I had used it to detect the events of action potential. I feel it good for me. I think the principle of detecting these two kinds of events are same. You can try to use pCLAMP 9.0 or higher edition (this function is added after 9.0) The problem: I don't know whether the filetype of your acquiring data could be opened by pCLAMP. But the axon file also have two column: time and amplitude. The difference of difference data filetype may be at the head of files. The follow is a example of axon file -- *.abf. ATF 1.0 7 2 "AcquisitionMode=Gap-Free" "Comment=" "YTop=100" "YBottom=-100" "SweepStartTimesMS=0.000" "SignalsExported=IN #15" "Signals=" "IN #15" "Time (s)" "Trace #1 (pA)" 0 -1.31836 4e-4 -1.51367 8e-4 -1.46484 0.0012 -1.51367 0.0016 -1.41602 0.002 -1.26953 0.0024 -1.5625 0.0028 -1.31836 I hope it can help you! good luck! From jonesmat from physiology.wisc.edu Tue Jun 24 12:42:08 2008 From: jonesmat from physiology.wisc.edu (jonesmat) Date: Tue Jun 24 17:18:17 2008 Subject: [Neuroscience] Re: What electrophysiology software are people using? References: <7968f31c-773e-45cf-8cd6-3a1e7cb83a81@j33g2000pri.googlegroups.com> Message-ID: <2ab2068f-c4aa-4e24-b98a-f6d93331dfa2@k30g2000hse.googlegroups.com> On Jun 23, 11:40?pm, Bill wrote: > Hi, > > I've been trying to find software that is actually functional for the > detection and subsequent analysis of spontaneous synaptic events. I've > tried using MiniAnalysis, which works, but is very unstable and about > as user friendly as a rusting syringe. We acquire data using CEDs > spike2, however it is no good for rejecting/accepting events, and it > doesn't have the necessary Stats (KS tests). For what ever reason, I > can't get WinEDR to open our data, and I can't get "Serf" (http://www.bram.org/serf/serf.php) to work. Axograph isn't available on PC > yet. > > What is pCLAMP like? Does anyone have any software that they would > actually recommend? Bill, Personally I think PClamp bites. Check the Axograph website again. It is available for PC now. Although it's no longer in beta testing, Axograph X is still not entirely bug free, even on Mac. But the detection works fine for us. I haven't used the PC version. But even with bugs I think it's better than most other packages. I am not sure it will do the stats you need (but maybe). We always use Prism for KS tests and such, after doing detection & measurement in Axograph. Matt From connelly.bill from gmail.com Tue Jun 24 15:30:44 2008 From: connelly.bill from gmail.com (Bill) Date: Tue Jun 24 17:18:40 2008 Subject: [Neuroscience] Re: What electrophysiology software are people using? References: <7968f31c-773e-45cf-8cd6-3a1e7cb83a81@j33g2000pri.googlegroups.com> <2ab2068f-c4aa-4e24-b98a-f6d93331dfa2@k30g2000hse.googlegroups.com> Message-ID: <40fbac55-326c-45ae-bc6f-3e0ac6b8f3ae@w4g2000prd.googlegroups.com> On Jun 25, 5:42?am, jonesmat wrote: > But even with bugs I think it's better than most other packages. I am > not sure it will do the stats you need (but maybe). We always use > Prism for KS tests and such, after doing detection & measurement in > Axograph. > > Matt Wait, hold the phone. Prism can do KS tests? I know it uses them to test for normality, but I didn't think you could use them to test between two distributions of your choice. Is that a standard feature? What version? Axograph is good (indeed the best I have seen), and I was at a neuroscience course in Australia (ACAN http://acan.jcs.anu.edu.au/acan.html) with John Clements, the guy who makes Axograph. We were running the PC version and it still wasn't 100% stable, certainly not stable enough for me to use it for acquisition of data (though John was bug fixing throughout the course, so maybe its better now). Indeed, if I could get it to work with our CED data loggers I would probably be trying to convince the boss the use it. From connelly.bill from gmail.com Tue Jun 24 15:36:26 2008 From: connelly.bill from gmail.com (Bill) Date: Tue Jun 24 17:18:44 2008 Subject: [Neuroscience] Re: question of inferior olive slice References: <5d4fe632-7607-4241-a86d-ec762c6d2f34@j33g2000pri.googlegroups.com> <26c41702-f2cc-44e5-af44-0f120e564339@z16g2000prn.googlegroups.com> <2b055f12-8951-4d2f-a09d-e1f0f6da6aad@p25g2000pri.googlegroups.com> Message-ID: <53eb9e9a-e3c8-4274-854b-853ac6cc863d@i36g2000prf.googlegroups.com> On Jun 25, 12:49?am, wwt wrote: > On Jun 24, 7:41?am, Bill wrote: > Thank you for your detaily answer. I will try more according your > advises. > A little question: What is the difference between Na ?Ascorbate and > Ascorbic acid? Can I use Ascorbic acid to replace the role of Na > Ascorbate? I'm not actually sure. Ascorbic acid isn't a carboxylic acid, so I don't know how reversible the reaction is, but I assume it is very reversible. From tehgabriel from web.de Wed Jun 25 08:25:35 2008 From: tehgabriel from web.de (Tom) Date: Wed Jun 25 12:40:12 2008 Subject: [Neuroscience] Re: Technical question: Alternative software for a "Coolsnap HQ" camera References: <4d10d8e2-632f-4066-ab3a-901261f5e956@k30g2000hse.googlegroups.com> <8b4acbda-061e-47c6-85a0-d9273a68164e@u12g2000prd.googlegroups.com> Message-ID: <41ac25e6-5105-42d5-919a-deaff3a1c74b@m73g2000hsh.googlegroups.com> Thanks for your reply, Bill! I just realised that i was not vey clear in my post. Of course there are several commercial software solutions but I was rather interested in open source programs. So far i found and tested. - micromanager - WinFluor Even though both programs look good (especially the micro-manager) and work very well, i found them to have some specific restrictions, that leaves them unsuitable for the experiments i have in mind. Regards, Thomas On 24 Jun., 07:21, Bill wrote: > I think the Coolsnap cameras can run a large number of programs. NIS > elements from nikon, or PMcapture from photometrics, and various > others. > > See:http://www.photomet.com/pm_downloads/software_pvcam.php > > On Jun 9, 9:56?pm, Tom wrote: > > > Hi! > > I have a 'Coolsnap HQ' from Princeton that came together with a > > software package called "WinView". > > Unfortunately this software is full of bugs and really a pain to use. > > So i am wondering if anybody knows an image acquisition software that > > can be used to control a 'Coolsnap HQ' camera? > > If possible, this software should run under linux, but windows is fine > > too. > > > It should allow high frequency imaging (up to 20 Hz), where the timing > > is triggered by an external device. > > I already tried a software called "micro-manager" but didn't find this > > suitable for my needs > > > Any comments are appreciated! > > > Regards, > > Thomas From usenet02 from out-of-phase.de Thu Jun 26 05:53:11 2008 From: usenet02 from out-of-phase.de (Christian Wilms) Date: Thu Jun 26 10:38:02 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> <1iihdrs.1px8y3v1fwmyf4N%usenet02@out-of-phase.de> <48532472$0$12975$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <1iij1kl.8a7xcz10ggndiN%usenet02@out-of-phase.de> <1653872d-fef6-4dcc-b46c-d6a088f73d11@w8g2000prd.googlegroups.com> Message-ID: <1ij54vu.1n6j6l3k2zhziN%usenet02@out-of-phase.de> I think a lot of this discussion stems from the insufficient precision of "LTP" there are so many different forms of long-term synaptic plasiticity being discussed in the literature, many of which rely on different and often independent mechaninms. It would be surprising, if these all had different temporal patterns of expression. Best, Christian From usenet02 from out-of-phase.de Thu Jun 26 05:53:11 2008 From: usenet02 from out-of-phase.de (Christian Wilms) Date: Thu Jun 26 10:38:09 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <1iij1o0.1c71ezk7s4vetN%usenet02@out-of-phase.de> Message-ID: <1ij54kp.12ldw7b16dhi6mN%usenet02@out-of-phase.de> Coming from the cerebellum, epileptiform isn't that much of a problem. Long-term plasticity of interneuron inputs is though and not using a GABA-A blocker should lead to very complex results (Mittmann and H?usser, 2007 goes into that direction). Personally, I think that the ideal situation is to record from pairs of identified neurons - keeping the obvious problems with that in the back of my mind of course ;) Cheers, Christian From decoy from mindyaown.biz Thu Jun 26 06:10:32 2008 From: decoy from mindyaown.biz (Entertained by my own EIMC) Date: Thu Jun 26 10:38:14 2008 Subject: [Neuroscience] Re: Long-term potentiation and depression References: <70f15b4c-f43a-4fdc-8dc3-d48126d3fb7d@e53g2000hsa.googlegroups.com> <1iifgvx.1y7rwd71anserqN%usenet02@out-of-phase.de> <4851cc59$0$13000$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <9hk3541so7j4teh5f252hmo27colba36gt@4ax.com> <1iihdrs.1px8y3v1fwmyf4N%usenet02@out-of-phase.de> <48532472$0$12975$5a62ac22@per-qv1-newsreader-01.iinet.net.au> <1iij1kl.8a7xcz10ggndiN%usenet02@out-of-phase.de> <1653872d-fef6-4dcc-b46c-d6a088f73d11@w8g2000prd.googlegroups.com> <1ij54vu.1n6j6l3k2zhziN%usenet02@out-of-phase.de> Message-ID: <48637923$0$19034$5a62ac22@per-qv1-newsreader-01.iinet.net.au> "Christian Wilms" wrote in message news:1ij54vu.1n6j6l3k2zhziN%usenet02@out-of-phase.de... >I think a lot of this discussion stems from the insufficient precision > of "LTP" there are so many different forms of long-term synaptic > plasiticity being discussed in the literature, many of which rely on > different and often independent mechaninms. It would be surprising, if > these all had different temporal patterns of expression. > > Best, Christian I appreciate what you are saying. It is because I am committed to my own attemptedly 'explanatory philosophical type' of agenda that I have resorted to using whatever approximately appropriate term available to make my point(s). :-) Regards, Peter From mpb1211 from uwyo.edu Mon Jun 30 17:16:54 2008 From: mpb1211 from uwyo.edu (Mary P. Brownson) Date: Mon Jun 30 18:03:03 2008 Subject: [Neuroscience] rat brain perfusion and fixation Message-ID: <85F291B637727346BA8274B0A43C24FF0272F921@TELEGRAPH1.uwyo.edu> Hello, I am working on perfusion and fixation of rat brains for the purpose of Fluoro-Jade staining after the brain has been sectioned with a cryostat. I am having problems with the brain sections looking like "Swiss cheese". Has anyone else had this problem? What can I do about this problem? I am using 4% paraformaldehyde in PBS. Any info/hints will be greatly appreciated. Thank you, Mary Brownson, Ph.D. School of Pharmacy University of Wyoming (307)766-6748