A KINETIC-MODEL OF SHORT-TERM AND LONG-TERM POTENTIATION

We present a kinetic model that can account for several experimental f indings on short- and long-term potentiation (STP and LTP) and their p harmacological modulation. The model, which is consistent with Hebb's postulate, uses the hypothesis that part of the origin of LTP may be a consequence of an increased release of neurotransmitter due to a retr ograde signal. The operation of the model is expressed by a set of irr eversible reactions, each of which should be thought of as equivalent to a set of more complex reactions. We show that a retrograde signal a lone is not sufficient to maintain LTP unless long-term change of the rate constant of some of the reactions is caused by high-frequency sti mulation. Pharmacological manipulation of LTP is interpreted as modifi cations of the rate constants of one or more of the reactions that exp ress a given mechanism. The model, because of its simplicity, can be u seful to test more specific mechanisms by expanding one or more reacti ons as suggested by new experimental evidence.