Topiramate diminishes fear memory consolidation and extinguishes conditioned fear in rats

Background: topiramate has been recognized as a drug that can induce memory and cognitive impairment. using the one-trial inhibitory avoidance task,we sought to verify the effect of topiramate on consolidation and extinction of aversive memory. our hypothesis was that topiramate inhibits the consolidation and enhances the extinction of this fear memory. methods: in experiment 1,which occurred immediately or 3 hours after training,topiramate was administered to rats,and consolidation of memory was verified 18 days after the conditioning session. in experiment 2,which occurred 18-22 days after the training session,rats were submitted to the extinction protocol. rats received topiramate 14 days before or during the extinction protocol. results: topiramate blocked fear memory retention (p < 0.01) and enhanced fear memory extinction (p < 0.001) only when administered during the extinction protocol. limitations: this experimental design did not allow us to determine whether topiramate also blocked the reconsolidation of fear memory. conclusion: topira mate diminishes fear memory consolidation and promotes extinction of inhibitory avoidance memory. © 2011 canadian medical association.