RESUMEN
Objective To investigate the effect of thyroid stimulating hormone (TSH) on the expression of endothelial nitric oxide synthase (eNOS) and its mechanism in human microvascular endothelial cells (HMEC-1) in vitro culture.Methods Different concentrations of TSH (0,10,50 mIU/ml) were used to intervene HMEC-1.The expression of eNOS mRNA was detected with quantitative polymerase chain reaction (qPCR) method.The protein expressions of eNOS,phosphorylated protein kinase B (p-AKT),protein kinase B (AKT),phosphorylated extracellular signal-regulated kinase (P-ERK),and extracellular signal-regulated kinase (ERK) were determined with Western Blot.Results (1) The expression level of eNOS was significantly decreased by TSH in dose-dependent manner (P ＜ 0.05).(2) TSH could promote the phosphorylation of AKT and ERK (P ＜ 0.05).Conclusions Thyroid-stimulating hormone may inhibit the expression of nitric oxide synthase in human microvascular endothelial cells by activating AKT and ERK signaling pathways.