Metaplasticity....

mat mats_trash at hotmail.com
Tue Apr 23 12:00:57 EST 2002


Nyquist <giddeon_nyquist at hotmail.com> wrote in message news:<fP7x8.5548$xv5.1728537 at carnaval.risq.qc.ca>...
> Hi there, 
> 
> I'm having some difficulty understanding the concept of "metaplasticity."
> While I have been attempting to read the literature, the material there is 
> something that I must be missing.  Is metaplasticity an event that happens 
> subsequent to LTP or other modes of plasticity causing the neuron to act 
> function differently if subjected to the same stimulus?
> 
> Also, if someone could explain why exactly after inducing LTP can LTD be 
> induced?  
> 
> Thanks for your attention, 
> -Nyquist

Metaplasticity is simply the term used to describe how the plasticity
of a synpase in response to a given stimulus changes with time.  For
example, if a particular synpase is potentiated to different degrees
by the same stimulus, then what regulates this change in effect and
how it varies over time is called the metaplasticity.  Like velocity
and acceleration really.  Metaplasticity is the description of the
higher-level processes that change the 'susceptibility' of synpases to
plastic change.  It thus incoroporates elements of the history of
activity at the synpase, which regulate how the synpase will react in
the local future.  Metaplasticity, more than plasticity itself,
involves the actions of neuromodulators such as substance P and other
slow acting agents which will have their effects over a relatively
extended period of time compared to the quick plastic changes that
occur at the synpase such as the relief of the Mg block on NMDA
receptors


as to your second question I'm not really that well versed, but from
what I do know I suspect it is highly specific to the individual type
of synpase.




More information about the Neur-sci mailing list