Quillfeldt J A, Zanatta M S, Schmitz P K, Quevedo J, Schaeffer E, Lima J B, Medina J H, Izquierdo I
Departamento de Bioquímica, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil.
Neurobiol Learn Mem. 1996 Sep;66(2):97-101. doi: 10.1006/nlme.1996.0050.
Rats were trained in a step-down inhibitory avoidance task and tested for retention 1, 31, or 60 days later. Three to 7 days prior to testing, they were bilaterally implanted with cannulae in the CA1 region of the dorsal hippocampus and in the amygdaloid nucleus (H + A), in the entorhinal cortex (EC), and in the posterior parietal cortex (PPC). Ten minutes prior to testing, the animals received, through the cannulae, 0.5-microliter microinfusions of vehicle (20% dimethylsulfoxide in saline) or of 0.5 microgram of CNQX dissolved in the vehicle. A second test session was carried out 90 min after the first. CNQX blocked retention test performance when given into H + A 1 day after training but not later; when given into EC 1 or 31 days after training, but not later; and when given into PPC 1, 31, or 60 days after training. In all cases performance returned to normal levels in the second test session. The data suggest that H and A are involved in memory expression for only a few days after acquisition; that EC is involved in memory expression for up to 31, but less than 60, days after acquisition; and that PPC is involved in memory expression for up to at least 2 months after acquisition.
大鼠接受了一步式抑制性回避任务训练，并在1天、31天或60天后进行记忆保持测试。在测试前3至7天，它们双侧植入套管，分别位于背侧海马体的CA1区域和杏仁核（H + A）、内嗅皮层（EC）以及顶叶后皮质（PPC）。在测试前10分钟，动物通过套管接受0.5微升的溶剂（20%二甲基亚砜溶于生理盐水）或溶于该溶剂的0.5微克CNQX的微量注射。在第一次测试后90分钟进行第二次测试会话。CNQX在训练后1天注入H + A时会阻断记忆保持测试表现，但之后则不会；在训练后1天或31天注入EC时会阻断测试表现，但之后则不会；在训练后1天、31天或60天注入PPC时也会阻断测试表现。在所有情况下,第二次测试会话中的表现均恢复到正常水平。数据表明，H和A仅在习得后的几天内参与记忆表达；EC在习得后长达31天但少于60天的时间内参与记忆表达；而PPC在习得后至少长达2个月的时间内参与记忆表达。
