My understanding is that LTP as usually studied IS "post-tetanic"
potentiation, because the usual procedure has been to use high rates of
suprathreshold stimulation, driving the neurons--i.e. into tetanus.
More recently, some have adopted a procedure using stimulation
parameters more like those occurring naturally, called "prime burst
potentiation" sometimes (or sometimes simply "LTP", but with
specification that the stimuli are not tetanic). It has been argued
that LTP accomplished this way is vulnerable to manipulations of
conditions that tetanic LTP is not (e.g. altered cortisol levels??),
and thus more physiologically relevant.
I don't know exact details of what Sturla refers to, but this may be
relevant: NO normally amplifies/perpetuates/spatially distributes
effects of NMDA activation, including enhanced LTP; but excessive or
untimely NO will block LTP. (see, for example, Izumi & Zorumski,
Neuroreport 1993, 4, 1131-1134; I had the pleasure of discussing this
with Izumi when he stopped by my poster at Society for Neuroscience,
F. Frank LeFever, Ph.D.
New York Neuropsychology Group
In <37090de3.25058581 at news.ox.ac.uk> james.teo at chch.ox.ac.uk (Grushnik)
>>On 2 Mar 1999 17:07:14 GMT, Sturla Molden <stumol at stud.ntnu.no> wrote:
>>>I have a technical question regarding LTP and PTP:
>>If LTP is induced massively in a brain slice (until
>>saturation level), will that also occlude new PTP
>>in the slice? Or, rephrased, do LTP and PTP have
>>some common expression mechnisms? I would be very happy
>>if anyone could direct me to recent litterature on the
>>I'm not too sure about this, but I thought PTP was an artefact of the
>electrical stimulation of the presynaptic cell. (ie. after a tetanus,
>there is an accumulation of calcium (or whatever signal)
>intracellularly and so less is needed if the cell is stimulated
>Perhaps what you mean is STP. In which case I can't help you since I
>don't know much about it either. I don't think much is known about it,
>although I do recall being told by my tutor or someone that they
>probably share some common elements.