Effects Of Iptakalim, A Novel K_ATP Channel Opener, On The Proliferation Of Cultured Human Pulmonary Arterial Smooth Muscle Cells Induced By Endothelin-1

Objective To explore the effects of iptakalim, a novel K_ATP channelopener, on the proliferation of cultured the human pulmonary arterialsmooth muscle cells (HPASMCs) induced by endothelin-1 (ET-1).Methods The models of proliferation of HPASMCs induced by ET-1 invitro were established and ³H-thymidine (³H-TdR) incorporation and flowcytometric analysis (FCA) were used.Results The enhanced ³H-thymidine incorporation was inhibited andthe transition of cells from static phase (G₀/G₁) to DNA synthesis (S) andmitotic phase (G₂/M) was held back by iptakalim in a concentration-dependent manner. Glibenclamide abolished the inhibitory effects ofiptakalim.Conclusion Iptakalim had the inhibitory effects on the proliferation ofhuman pulmonary arterial smooth muscle cells induced by ET-1 throughactivation of K_ATP channels.These findings suggest that iptakalim might be a promising candidate for the treatment of pulmonary arterialhypertension.