[Effects of S-adenosyl-L-methionine on experimental cerebral ischemia]

Effects of S-adenosyl-L-methionine (SAMe) on experimental cerebral ischemia were investigated using two different ischemic models. Cerebral energy metabolites (ATP, lactate, c-AMP) and brain water content were measured. It is reported that SAMe accelerates synthesis of phosphatidyl choline and increases erythrocyte membrane fluidity. Complete ischemia was produced by heart excision using wistar kyoto rats. SAMe (100 mg/kg, I.P.) was administered twice at one hour and immediately before inducing ischemia. The brain of rats were irradiated by microwave to stop the enzyme activity exactly 60 seconds after inducing ischemia and brain energy metabolites were measured. Recirculation model was produced by one hour recirculation following two hours ischemia induced by clipping of bilateral common carotid arteries using stroke-prone spontaneously hypertensive rats. SAMe (100 mg/kg, I.V.) was administered twice one hour after clipping and ten minutes after recirculation. The brain metabolites and water content were measured one hour after recirculation. In the complete ischemia, ATP and c-AMP levels were statistically high in the SAMe treated group compared to the untreated group (vehicle). But there was no statistical difference in lactate between the treated group and the untreated group. In the recirculation model, lactate elevation was suppressed in the SAMe treated group compared to the vehicle group with statistical difference, but there was no difference in ATP and c-AMP. Also, there was no difference in water content between the treated and the untreated group. SAMe protected energy failure in ischemia and accelerated recovery from ischemia. It is indicated that this agent is beneficial for treatment of cerebral ischemia in the acute stage.