Study on eNOS phosphorylation induced by monomethylarsonous acid

ObjectiveTo observe the effects of monomethylarso nous acid(MMAⅢ)on eNOS phosphor ylation and reactive oxygen species(ROS)generation in bovine aortic endothelial cells(BAEC).MethodCultured BAEC was exposed to MMAⅢ(0.75 μmol/L,0~15 min)without or with acetylcysteine(NAC)pretreatment(1 mmol/L,2 h),or iAsⅢ(100 Lmol/L,0~60 min).Western blot was done with the specific antibodies for phospho-eNOS_Ser1179.Intracellular ROS generation was assessed with the fluorescent probe,2',7'-dichlorodihydrofluorescein diacetate(H2DCFDA).ResultsMMAⅢ (0.75 μmol/L)caused a rapid increase in phosphorylated eNOS_Ser1179 at 15 min after exposure(P<0.05).In contrast,up to 100 μmol/L iAsⅢ caused the increase of phosphorylated eNOS_Ser1179 at 30 min(P<0.05).MMAⅢs timulated the ROS production in live cells.Both the MMAⅢ-induced eNOS_Ser1179 phosphory lation and ROS generation were blocked by NAC pretreatment(1 mmol/L,2 h).ConclusionMMAⅢ exposure can induce ROS generation and ROS-dependent eNOS phosphor ylation.