K_(ATP)通道与人肺动脉平滑肌细胞外信号调节激酶磷酸化的关系

Relationship between ATP-sensitive potassium channel and the phosphorylation of ERK1/2 in human pulmonary arterial smooth muscle cells

目的研究三磷酸腺苷(ATP)敏感性钾(KATP)通道与人肺动脉平滑肌细胞外信号调节激酶1和2(ERK1/2)磷酸化的关系。方法原代培养人肺动脉平滑肌细胞,用Western-blot方法检测磷酸化细胞外信号调节激酶1和2(p-ERK1/2)。对照组不予干预,实验组分别加入内皮素-1(ET-1)、ET-1+埃他卡林、吡那地尔或格列本脲等孵育。结果①在2～30 min,ET-1呈时间依赖性促进人肺动脉平滑肌细胞ERK1/2磷酸化,10 min时最明显。②埃他卡林和吡那地尔可拮抗ET-1对ERK1/2磷酸化的影响。③特异性KATP通道阻断剂格列本脲可逆转埃他卡林和吡那地尔的作用。结论KATP通道开放剂可能通过激活KATP通道,抑制ET-1诱导的原代培养人肺动脉平滑肌细胞ERK1/2磷酸化,KATP通道可能是研发新型治疗肺动脉高压药物的重要靶分子。

Objective To study the relationship between ATP-sensitive potassium channel and the phosphorylation of extracellular signal regulated kinase 1/2 （ERK1/2） in human puhnonary arterial smooth muscle cells. Methods By Western-blot analysis, the phosphorylation levels of ERK1/2 were measured in primary cultured human pulmonary arterial smooth muscle cells. Except for no intervention for control group, other groups were incubated with endothelin-1 （ ET-1 ）, ET-1 ＋ iptakalim, pinacidil or glibenclamide. Results ①ET-1 induced phosphorylation of ERK1/2 from 2 to 30 min with a peak response observed at 10 min in a time-dependent manner. ②Iptakalim and pinacidil inhibited ET-1-induced ERK1/2 phosphorylation. ③Glibenclamide, a selective KATP channel antagonist, could antagonize the effects of iptakalim and pinacidil. Conclusions KATP channel openers inhibited ET-1-induced phosphorylation of ERK1/2 in primary cultured human pulmonary arterial smooth muscle cells probably through activating KATP channel and KATP channel will be most promising target for new drugs to treat pulmonary arterial hypertension.