Effect of Extract of Astragalus on Alterations of Blood Brain Barrier Induced by Local Cerebral Ischemia-reperfusion Injury

OBJECTIVE To study the effect of extract of astragalus (EA) on alterations of blood brain barrier after local cerebral ischemia-reperfusion injury in rats. METHODS Middle cerebral artery occlusion (MCAO) was used to make local cerebral ischemia-reperfusion model with intravascular nylon filament occlusion. The neurological function score, brain edema and infarct volume, the counts of peripheral blood circulating cells, the expression of intercellular adhesion molecule-1, pathological changes in blood-brain barrier ultrastructure in rats after focal cerebral ischemia-reperfusion were observed. RESULTS EA 80 mg·kg^-1 decreased the neurological function score; EA(40 and 80 mg·kg^-1) reduced brain edema and infarct volume, the counts of peripheral blood circulating cells, pathological changes in blood-brain barrier ultrastructure; EA(20, 40 and 80 mg·kg^-1) decreased the expression of intercellular adhesion molecule-1 in brain tissue. CONCLUSION EA has protective effects against cerebral ischemia reperfusion injuries, the mechanism may be related with reducing BBB injury induced by local cerebral ischemia-reperfusion.