Izquierdo I, Pereira M E
Departamento de Biquimica, Instituto de Biociencias, U.F.R.G.S., Porto Alegre, Brazil.
Behav Neural Biol. 1989 Jan;51(1):108-13. doi: 10.1016/s0163-1047(89)90725-5.
Rats were trained in a step-down inhibitory avoidance task using a 0.2-mA footshock and tested 6 h later. Exposure to a session of extinction (animals placed on the box where they had been trained and left to explore it freely for 100.0 s without footshocks) or to a series of 10 tones presented in another box, in the dark, 2 h after training, hindered retention test performance. The immediate post-training ip administration of epinephrine (5.0 micrograms/kg), ACTH-(1-24) (0.2 microgram/kg), or lysine-vasopressin (10.0 micrograms/kg) facilitated retention test performance and cancelled the effect of extinction, but not the retroactive interference caused by exposure to the tones. These results support the concept that post-training facilitation induced by the hormones is due to a strengthening of the memory trace left by the avoidance task, whereas the retroactive interference caused by the tones occurs independently from that process and is more likely due to the incorporation of postevent information.
使用0.2毫安的足部电击对大鼠进行逐步抑制性回避任务训练，并在6小时后进行测试。训练后2小时，让动物暴露于消退阶段（将动物放置在其接受训练的箱子中，让它们在无电击的情况下自由探索100.0秒）或在另一个箱子中在黑暗中呈现一系列10次音调，这会妨碍记忆保持测试表现。训练后立即腹腔注射肾上腺素（5.0微克/千克）、促肾上腺皮质激素（1-24）（0.2微克/千克）或赖氨酸加压素（10.0微克/千克）可促进记忆保持测试表现并消除消退的影响，但不能消除暴露于音调所引起的逆向干扰。这些结果支持这样一种概念，即激素诱导的训练后促进作用是由于回避任务留下的记忆痕迹得到加强，而音调引起的逆向干扰独立于该过程发生，并且更可能是由于事件后信息的整合。
