Boccia M M, Blake M G, Acosta G B, Baratti C M
Laboratorio de Neurofarmacología de Procesos de la Memoria, Cátedra de Farmacología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Argentina.
Neuroscience. 2005;135(1):19-29. doi: 10.1016/j.neuroscience.2005.04.068.
CF-1 male mice were trained in an inhibitory avoidance task using a high footshock (1.2mA, 50Hz, 1 s) in order to reduce the influence of extinction on retention performance. A single session of 5 min exposure to a hole-board (nose-poke behavior), either immediately after training or the first retention test (memory reactivation) impaired retention performance over two consecutive days. The effects were time-dependent since they were not observed when the exposure to the hole-board was delayed 3 h. When mice were habituated to the hole-board (5 min/day, 5 days), and then trained in an inhibitory avoidance task, the immediately post-training or memory reactivation exposure to the hole-board did not modify retention performance over two consecutive days. The effects of the post-reactivation acute exposure to the hole-board were long-lasting (21 days). Reinstatement was not observed in our experimental conditions. The non-spontaneous recovery of retention performance over 21-days and the lack of reinstatement, suggest that the impairment of retention performance observed was not probably due to a deficit in memory retrieval. These findings suggest that the exposure to a potential new learning situation impairs not only memory consolidation but also memory reconsolidation of the original learning task.
CF-1雄性小鼠使用高强度电击（1.2毫安，50赫兹，1秒）在抑制性回避任务中接受训练，以减少消退对记忆保持表现的影响。在训练后或首次记忆保持测试（记忆再激活）后立即进行单次5分钟的洞板暴露（探鼻行为），会损害连续两天的记忆保持表现。这些影响是时间依赖性的，因为当洞板暴露延迟3小时时未观察到这些影响。当小鼠适应洞板（每天5分钟，共5天），然后在抑制性回避任务中接受训练时，训练后或记忆再激活后立即进行的洞板暴露在连续两天内并未改变记忆保持表现。再激活后急性暴露于洞板的影响是持久的（21天）。在我们的实验条件下未观察到恢复现象。记忆保持表现在21天内的非自发恢复以及恢复现象的缺乏，表明观察到的记忆保持表现受损可能并非由于记忆检索缺陷所致。这些发现表明，暴露于潜在的新学习情境不仅会损害记忆巩固，还会损害原始学习任务的记忆再巩固。
