Cognitive Deficits After Focal Cerebral Ischemia in Mice

Abstract

Background and Purpose—The interpretation of cognitive data in many experimental stroke studies is problematic because middle cerebral artery occlusion (MCAO) is associated with sensorimotor alterations that may become confounding factors in cognitive testing. The purpose of the current study was to determine if it is possible to measure MCAO-induced cognitive deficits by using short durations of ischemia that do not result in alterations in sensorimotor behavior in mice. Methods—Male C57/Bl6 mice were subjected to 60 or 90 minutes of intraluminal MCAO or sham surgery. In the first cohort of animals (n=12/group), locomotor activity, balance, and coordination were evaluated 2 weeks after surgery. In a second cohort of animals (n=10/group), the effects of 60 minutes of MCAO on subsequent learning and memory were assessed with a step-down passive avoidance task beginning 1 week after surgery. In a third cohort of animals (n=8 to 10/group), training in a passive avoidance task was completed before 60 minutes ...