Memory and learning are considered as the most complicated and important processes of behavioral sciences. On the other hand, considering the wide .and progressively increasing applications of anesthetic agents all over the world, it is of great importance to have a reasonable knowledge regarding their effects on the memory process and its retrieval. The main purpose of this study was to evaluate anterograde and retrograde effects of isoflurane anesthesia on the memory process. For this purpose, male rats were divided into one control and two treatment groups. All of the groups underwent the training program of single trial passive avoidance learning, and the treatment groups (b and c) were exposed to isoflurane anesthesia (1.4% for 60 min) before and after the learning program. After 24 hours, the memory retrieval test was performed. The results showed that the mean retention latency value (which was considered as total in the control groups and measured as 600 sec) significantly decreases to 139 and 179 sec in groups b and c respectively (p<0.05). It can be concluded that that administration of isoflurane both before and after learning program causes disturbances in retrieval process of memory and also results in anterograde and retrograde amnesia in rats.

Keywords: Isoflurane; Memory; Passive avoidance learning; Anterograde and retrograde amnesia