Department of Psychology, McGill University, 1205 Dr. Penfield Ave., Montreal, Quebec, Canada H3A 1B1.
Behav Brain Res. 2011 Jan 1;216(1):281-4. doi: 10.1016/j.bbr.2010.08.009. Epub 2010 Aug 14.
Previously consolidated memories may become labile when they are reactivated and require reconsolidation. It has been suggested that when novel information is present at the time of memory reactivation reconsolidation is engaged but when no new information is present, reconsolidation may not occur, and extinction may be the dominant process instead. To test this idea we trained rats to associate a context with the rewarding properties of morphine (5 mg/kg, sc) over four conditioning pairings. Following training, animals were reactivated by a 30-min test session, once a day for 3 days. Rats were injected with the amnestic drug propranolol (10 or 40 mg/kg, sc) following reactivation either on the first or on the second day. They received saline on the alternate day. Propranolol disrupted reconsolidation for a conditioned place preference only when given on the first reactivation day, and this effect was more robust following the higher dose of propranolol. In contrast, animals given propranolol on the second reactivation day still displayed a preference for the morphine-paired context on the final test day. These results support the view that for memory to return to a labile state, the situation that evokes reactivation needs to be novel in some way. If the reactivation situation is familiar, reconsolidation may not occur.
先前巩固的记忆在被重新激活时可能变得不稳定，需要重新巩固。有人提出，当新信息在记忆重新激活时出现，重新巩固就会发生，但当没有新信息出现时，重新巩固可能不会发生，而灭绝可能是主导过程。为了验证这一观点，我们训练大鼠将一种环境与吗啡（5mg/kg，sc）的奖赏特性联系起来，共进行了四次条件配对。训练结束后，动物在 3 天内每天接受 30 分钟的测试，以进行重新激活。在重新激活后，动物被注射遗忘药物普萘洛尔（10 或 40mg/kg，sc），分别在第一天或第二天。它们在交替日接受生理盐水。只有当普萘洛尔在第一天的重新激活日给予时，才会破坏条件性位置偏好的重新巩固，而较高剂量的普萘洛尔的效果更明显。相比之下，在第二天的重新激活日给予普萘洛尔的动物在最后一次测试日仍然对吗啡配对的环境表现出偏好。这些结果支持这样一种观点，即记忆要恢复到不稳定状态，重新激活的情况需要以某种方式具有新颖性。如果重新激活的情况是熟悉的，重新巩固可能不会发生。
