BENEFICIAL-EFFECTS OF S-ADENOSYL-L-METHIONINE ON BLOOD-BRAIN-BARRIER BREAKDOWN AND NEURONAL SURVIVAL AFTER TRANSIENT CEREBRAL-ISCHEMIA IN GERBILS

We have studied the beneficial effects of S-adenosyl-L-methionine (SAM ) tosylate on blood-brain barrier (BBB) breakdown and neuronal surviva l after transient cerebral ischemia in gerbils. BBB breakdown experime nts were performed in pentobarbital anesthetized gerbils subjected to 10 min of bilateral carotid artery occlusion and 6 h of reperfusion. F or BBB breakdown measurements, SAM (120 mg/kg, i.p.) was administered to gerbils just after occlusion and thereafter every hour up to 5 h. F luorometric measurements quantified the blood-brain permeability trace r, Evans blue (EB). SAM treatment significantly reduced the BBB breakd own as indicated by reduced levels of EB fluorescence. Neuronal count experiments were conducted in gerbils subjected to transient ischemia and 7 days of reperfusion. For neuronal count experiments SAM(15-120 m g/kg) was administered at 6 and 12 h after reperfusion, and twice each day thereafter for 7 days. SAM dose dependently protected the hippoca mpal CAI neurons assessed by histopathological methods. SAM has a bene ficial effect on the outcome of ischemic injury by reducing the BBB br eakdown and neuronal death.