Protective effect of losartan on bovine cerebral microvessel endothelial cell injury induced by angiotensin II in culture

AimTo investigate the protective effects of losartan on bovine cerebral microvessel endothelial cell (BCMEC) injury induced by angiotensin II (Ang II) in culture. MethodsIn this study, cultured bovine cerebral microvessel endothelial cells were used and the lactate dehydrogenase (LDH) leakage from bovine cerebral microvessel endothelial cells were observed. Flow cytometry was used to evaluate intercellular adhesion molecule-1 (ICAM-1) expression in bovine cerebral microvessel endothelial cells. Supernatant nitric oxide (NO) and endothelin-1 (ET₁) contents in bovine cerebral microvessel endothelial cells were measured, by NO assay kit and radioimmunoassay, respectively. ResultsAngiotensin II, in a dose-dependent manner, increased lactate dehydrogenase leakage, NO and ET₁ releases, intercellular adhesion molecule-1 expression of bovine cerebral microvessel endothelial cells. These effects induced by 1×10^-6 mol·L^-1 angiotensin II were all significantly inhibited by 1×10^-5 mol·L^-1 losartan. ConclusionAngiotensin II may be involved in the initiation and progression of cerebrovascular disease by injuring cerebral endothelium directly and causing endothelial dysfunction. Losartan was shown to protect against angiotensin II-induced bovine cerebral microvessel endothelial cells injury by blocking AT₁ receptor, suggesting that losartan may play a role in the prevention and treatment of cerebrovascular diseases.