Bianchin M., Da Silva R.C., Schmitz P.K., Medina J.H., Izquierdo I.
Departamento de Bioquimica, Instituto de Biociencias, Universidade Federal do Rio Grande Do Sul, 90046-900 Porto Alegre, RS, Brazil.
Behav Pharmacol. 1994 Jun;5(3):356-359. doi: 10.1097/00008877-199406000-00014.
This experiment investigated the effect on memory, in rats, of the bilateral intrahippocampal post-training infusion of the glutamate metabotropic receptor (mGLUR) agonist, ACPD (1S, 2R-aminocyclopentane dicarboxylate) and of the mGLUR antagonist, MCPG ([RS]-alpha-methyl-4-carboxyphenyl glycine). Male Wistar rats were implanted bilaterally with cannulae in the CA1 region of the dorsal hippocampus. After recovery from surgery they were trained in a step-down inhibitory avoidance task and tested for retention 24h later. Immediately or 180min after training they received a bilateral intrahippocampal infusion of saline (0.5µl), ACPD (1.0 or 2.5µg/side), MCPG (2.5µg/side) or ACPD plus MCPG, in 0.5µl saline. Upon immediate post-training infusion, ACPD caused a dose-dependent enhancement of memory and MCPG was amnestic. The effect of MCPG was antagonized by the simultaneous administration of ACPD. When given 180min after training, the drugs had no effect on memory. The results indicate that the early phase of memory is regulated by mGLURs in the hippocampus, and support the suggestion that memory involves long-term potentiation initiated at the time of training in the hippocampus.
本实验研究了在大鼠中，双侧海马内训练后注入代谢型谷氨酸受体（mGLUR）激动剂ACPD（1S，2R -氨基环戊烷二羧酸）和mGLUR拮抗剂MCPG（[RS]-α-甲基-4-羧基苯基甘氨酸）对记忆的影响。雄性Wistar大鼠双侧在背侧海马CA1区植入套管。术后恢复后，它们接受了一步式抑制性回避任务训练，并在24小时后进行记忆保持测试。训练后立即或180分钟后，它们在0.5微升生理盐水中接受双侧海马内注入生理盐水（0.5微升）、ACPD（1.0或2.5微克/侧）、MCPG（2.5微克/侧）或ACPD加MCPG。训练后立即注入时，ACPD引起剂量依赖性的记忆增强，而MCPG具有遗忘作用。同时给予ACPD可拮抗MCPG的作用。训练后180分钟给予药物时，对记忆无影响。结果表明，记忆的早期阶段受海马中mGLURs的调节，并支持记忆涉及在海马训练时启动的长期增强作用这一观点。
