In article <OQkI5.1854$AD1.66184 at typhoon1.ba-dsg.net>, "Bill Browning"
<bbrownin at nospambellatlantic.net> wrote:
> What mechanism carries substances along the axon, inside it? Surely, simple
> Fick's Law diffusion would take years to move along that long slender
> Bill B.
there are motor molecules that actively transpost organelles along the
axon, proteins on the other hand are transported much MUCH more slowly (i
forget hte order, but something along the lines of millimeters per day)
PS- thanks rich (and the dream quote is from a moby song, it hits me hard
though, thats why i made it a sig... at least for a little while)
> Richard Norman <rsnorman at mediaone.net> wrote in message
> news:9JhI5.2032$EA6.137446 at typhoon.mw.mediaone.net...> > "mike" <mike-anderson at nwu.edu> wrote in message
> > news:mike-anderson-2110000251100001 at dhcp083174.res-hall.nwu.edu...> > > i am confused as to the direction that different molecules travel along
> > > the axon, i know that organelles can be carried antero, or retrograde,
> > > what about things such as nerve growth factor? Just a little confused.
> > > Forgive me if this is the wronog place to ask.
> > > --
> > > mike
> > > In my dreams i'm dying all the time
> > > http://www.mp3.com/mikeanderson> >
> > This is a good place to ask. I believe it is possible for pretty much
> > anything
> > inside the neuron to be carried in any which direction. What is more to
> > point is where is the stuff likely to come from?
> > If a cell is manufacturing a protein, then that must be done in the rough
> > ER in the soma. Therefore it will be transported anterograde down the
> > axon. On the other hand, if a protein is made somewhere else outside
> > the cell and acts as a signaling agent, then it is possible for it to be
> > picked up by endocytosis and transported. So something that is picked
> > up at the axon terminal (where the vesicle recycling allows for a lot of
> > that
> > kind of thing) might well be transported retrograde back to the cell body
> > Something picked up in the soma or dendrite area might be transported
> > anterograde down the axon.
> > I don't know specifically where nerve growth factor fits in the story.
> > And I would suggest you talk to someone about your dreams!
In my dreams i'm dying all the time