Effects of Iptakalim on the expression of KATP protein in cultured human pulmonary artery smooth muscle cells induced by endothelin-1

Objective:To investigate the effects of Iptakalim,a novel ATP-sensitive potassium channel opener(KATPCO),on the expression of ATP-sensitive potassium channel(KATP) protein in cultured human pulmonary artery smooth muscle cells(HPASMCs) induced by endothelin-1(ET-1). Methods:By Western- blot analysis,the expression of both SUR2B and Kir6.1,subunits of KATP protein,was detected in primary cultured HPASMCs,which were randomly divided into control group,ET-1 group,ET-1+ Iptakalim group,ET-1+ Pinacidil group,ET-1+ Iptakalim+ Glibenclamide group and ET-1+ Pinacidil+ Glibenclamide group. Results:Compared with ET-1,Iptakalim could upregulate the SUR2B subunit expression,which could be inhibited by Glibenclamide,a particular ATP-sensitive potassium channel blocker. However,there was no significant difference in Kir6.1 subunit expression in each group. Conclusion:Iptakalim,a new potential candidate in the treatment of hypoxic pulmonary hypertension(HPH),could play an important role by upregulating the expression of SUR2B subunit.