Effect of a contralateral lesion on neurological recovery from stroke in rats.

ABSTRACT

PURPOSE: Clinical studies suggest a correlation between changes in activity of the contralesional cerebral cortex and spontaneous recovery from stroke, but whether this is a causal relationship is uncertain. METHODS: Young adult Sprague-Dawley male rats underwent unilateral or bilateral permanent distal middle cerebral artery occlusion (dMCAO). Infarct volume was determined by 2,3,5-triphenyltetrazolium chloride (TTC) staining 24 hr after dMCAO, and functional outcome was assessed 1-28 days after dMCAO using the ladder rung walking and limb placing tests. RESULTS: Infarct volume was unchanged, but functional neurological deficits were reduced 1 day after bilateral compared to unilateral dMCAO. CONCLUSIONS: Activity in the contralesional cerebral cortex may inhibit functional motor recovery after experimental stroke.