EVIDENCE FOR ACTIVATION OF NMDA RECEPTORS WHEN MEMORY FUNCTION IS REINSTATED IN RATS WITH GLUTAMATERGIC TEMPORAL SYSTEMS DISRUPTED

Disruption of the fiber connections between the temporal cortex (TC) a nd lateral entorhinal cortex (LEC) results in impaired memory and decr ease of glutamate in both denervated areas. Administration of glutamat ergic agonists fully restores the mnemonic function in rats with TC/LE C lesions. The purpose of the present study was to examine whether the pharmacologically supported recovery of function may act via NMDA rec eptors. Rats with TC/LEC lesions either received saline, the NMDA anta gonist HA-966, the NMDA agonist glycine or HA-966 + glycine. The resul ts show that saline-treated rats are severely impaired in retention, w hereas rats treated with glycine perform like normal controls. Rats pr etreated with HA-966 are not able to profit from the beneficial effect s of glycine. These data support the notion that the restoration of me mory function obtained by glycine in lesioned animals involves activat ion of NMDA receptors.