GLYCINE FACILITATES INDUCTION OF LONG-TERM POTENTIATION OF EVOKED-POTENTIAL IN RAT HIPPOCAMPUS

Effects of glycine were investigated in Schaffer/commissural-CA1 pyramidal cell synapses of the rat hippocampal slices. Perfusion of glycine (0.05 mM) did not change baseline population spikes evoked by test stimulation but significantly enhanced short-term potentiation induced by a single shorter tetanus (100 Hz, 11 impulses); the effects resulted in production of long-term potentiation (LTP). LTP produced by a longer tetanus (100 Hz, 100 impulses, 2 trains) was not significantly influenced. Higher concentration (0.5 mM) of glycine increased the baseline spike amplitude. All these effects of glycine were not observed in the presence of 10-5 M 2-amino-5-phosphonovalerate, an N-methyl-d-aspartate (NMDA) antagonist. These results demonstrate that glycine can facilitate induction of LTP probably by activating NMDA receptor. © 1990.