[Posttetanic and frequency potentiation in slices of the olfactory cortex from the rat brain].

A 15-sec tetanization of lateral olfactory tract at the frequency of 30/sec produced a short-term (20 min) posttetanic potentiation of the field potentials (FPs) in the rat olfactory cortex slices. Rhythmical stimulation of lateral olfactory tract (6 trains of 10 pulses each at the frequency of 10/sec, with 4-5 sec intertrain interval) evoked a progressive increase in the amplitude of postsynaptic components of the FPs (EPSP and IPSP) but not in amplitude of presynaptic component--the compound AP of lateral olfactory tract. The findings suggest the development of the 2-form functional plasticity: posttetanic and frequency potentiation in pyriform cortex.