Evaluation of effects of memantine on cerebral ischemia in rats.

OBJECTIVE To evaluate the effects of memantine on infarct size in cerebral ischemia and on neurological outcome after temporary middle cerebral artery occlusion (MCAO) and reperfusion in rats. METHODS In this study, performed between 2002-2004 in Dicle University School of Medicine, Diyarbakir, Turkey, 30 adult Sprague-Dawley rats were used. Cerebral ischemia was constituted by the intraluminal filament method with a 4-0 nylon suture. Reperfusion was started after 2 hours of MCAO. The rats were randomly divided into 2 groups as control and memantine. Saline 0.9% (0.5 ml/kg) and memantine (30 mg/kg) were administered via nasogastric intubations. Three coronal slices of 2 mm thickness were obtained from cerebrum, cerebellum, and brain stem, and were stained with a 2% solution of triphenyltetrazolium chloride. Transparent sheets were placed over each section and the areas of the brain and infarct were measured. RESULTS Forty-five slices from each group (total 90) were obtained. Percent of ischemic area (%) in cerebrum, cerebellum, and brain stem level in memantine was lower than those of the control group (p<0.0001). In addition, we determined an improvement in neurological score at 24th and 72nd hours in the rats that have been given memantine. The memantine group showed significantly better recovery than the control group (p<0.0001). CONCLUSION We concluded that memantine may decrease ischemic area in experimental cerebral ischemia in rats and it seems that memantine may be beneficial in cerebral ischemia.