Transient focal ischemia induces motor deficit but does not impair the cognitive function in middle cerebral artery occlusion model of stroke in rats.

The effect on cognition was evaluated in the transient ischemia model of stroke in rats. Male Wistar rats were subjected to 2 h of transient ischemia by occluding the middle cerebral artery using the 4-0 intraluminal nylon thread. Neurological tests performed after 24 h, 7 and 15 days of middle cerebral artery (MCA) occlusion showed motor impairment as evidenced by decrease in the rota rod performance test. This was also confirmed histologically. However, when the learning and memory tests were performed, no change was observed in the learning and behavior as evidenced by insignificant difference in the retention latency in the passive avoidance test (334+/-31 s) and the transfer latency in the elevated plus maze (11+/-4.5 s) as compared to the sham-operated rats 369+/-34 and 8+/-1.7 s, respectively. The results of the present study demonstrates that transient occlusion of middle cerebral artery does not impair the learning and memory behavior of the rats.