RESUMO
Objective This study explored whether EPAS1 gene is involved in the proliferation of pulmonary arterial smooth muscle cells (PASMCs) during hypoxia when EPAS1 gene expression was interfered by small interfering RNA (siRNA).Methods The rat primary pulmonary artery smooth muscle cells were cultured and identified by immunofluorescence.The specific lipidosomes of EPAS1 siRNA were constructed and transfected into PASMCs,and the best targets were selected from the three interfering targets.The transfected PASMCs were cultured in hypoxia (37℃,5％ CO2,2％ O2) or normoxia (37℃,5％ CO2,20％ O2) for 24h,48h and 72h,respectively.The PASMCs proliferation was detected by CCK-8 assay.The protein expression of EPAS 1 and vascular endothelial growth factor (VEGF) were determined by Western blotting to investigate the effect of silencing EPAS1 gene expression on the proliferation of PASMCs under hypoxic condition.Results The specific liposomes ofEPAS1 siRNA were successfully constructed and transfected into PASMCs,and the best interfering target were selected from the three interference targets.The proliferation of PASMCs was increased and the protein expression of VEGF was up-regulated in the PASMCs under hypoxic condition.Under hypoxic or normoxic condition,PASMCs proliferation and VEGF protein expression of PASMCs were suppressed by EPAS 1 siRNA.Conclusion EPAS 1 gene might be involved in the proliferation of rat PASMCs by regulating VEGF protein level under hypoxic condition.