Bilateral ischaemic lesions of the medial prefrontal cortex are anxiogenic in the rat

Objective: Stroke patients often suffer from delayed disturbances of mood and cognition. In rodents, the prefrontal cortex (PFC) is involved in both higher order cognition and emotion. Our objective was to determine if bilateral focal ischaemic lesions restricted to the medial prefrontal cortex (mPFC) could be used to model post-stroke anxiety and/or cognitive deficits. Methods: Groups of adult male Sprague-Dawley rats (n = 9) received bilateral injections of either endothelin-1 (ET-1) (400 pmol) or vehicle (artificial cerebrospinal fluid) into the mPFC and were tested at various times using both a test of temporal order memory and in an elevated plus maze. Lesions were verified histologically. Results: ET-1 lesioned rats had reduced mobility on post-surgery day 8 that had resolved by day 29 at which time they spent significantly more time in the closed arm of the plus maze Conclusion: We conclude that ischaemic lesions localised to the mPFC can be used to model post-stroke anxiety in rats.