S-emopamil ameliorates ischemic brain damage in rats: Histological and behavioural approaches

Transient ischemia induced by 4 vessel occlusion (4VO) in rats is known to produce neuronal damage to particular brain structures such as the CAl sector of the hippocampus. Behavioural changes associated with ischemic lesioning of this brain region are an impairment in spatial learning of rats tested in a water maze (14). In the present study, it was investigated whether pretreatment with S-emopamil, a Ca2+-channel blocker as well as a 5-HT2 antagonist, prevents the occurence of hippocampal cell damage and/or spatial learning impairments in rats subjected to 4VO. Neuronal lesioning in the hippocampus was significantly reduced following pretreatment with S-emopamil in 4VO rats. In addition, S-emopamil treated animals showed an improved spatial learning ability compared to saline treated 4VO rats. It is suggested that S-emopamil may exert a protective effect under ischemic conditions. The possible mechanisms involved are discussed.