A long‐term locomotor function and cognition study following middle cerebral artery occlusion in rats

A long-term study of a cerebral ischemia model, considered valuable in developing better treatments of ischemia, was performed to understand the nature of the dysfunctions associated with stroke. This study focused on the behavioral recovery and cognitive learning and memory of rats over a 17-week period following middle cerebral artery occlusion (MCAO). The present study involved the design of a comprehensive guideline for clinical behavior evaluation. The behavior of ischemic rats was examined over 17 weeks from 4 different aspects: posture & balance tests (4 subtests), reflex tests (6 subtests), muscle-tone tests (3 subtests), and a foot-fault test. After the tests, the results were analyzed to reveal the relationship between hemispheric atrophy and functional evaluation scores. Each battery of behavioral tests revealed multiple recovery phases in the time courses. Also, in the passive avoidance test, the MCAO group differed significantly from the sham group until 8 weeks, at which point the latencies to the sham group levels had occurred and after which there was no significant difference until 17 weeks. Thus, the present study provides a valuable protocol in long-term neuroprotection studies and presents an important profile of motor function that will supplement standard histopathological analysis at a later stage of ischemia.