西地那非抑制低氧对人肺动脉平滑肌细胞电压依赖性钾通道的下调作用  

Sildenafil inhibits hypoxia-induced voltage-dependent potassium channels downregulation in human pulmonary artery smooth muscle cells

作　　者：毛婷[1,2] 王跃秀[1,2] 刘杰[1,2] 李晶[1,2] 王军[1,2] 

机构地区：[1]首都医科大学基础医学院生理学教研室,北京100069 [2]首都医科大学附属北京朝阳医院北京市呼吸和肺循环疾病重点实验室,北京100020

出　　处：《首都医科大学学报》2013年第2期224-231,共8页Journal of Capital Medical University

基　　金：国家973计划项目(2009CB522107);国家自然科学基金(81070042);重大国际合作研究基金项目(30810103904);海外及港澳学者合作研究基金(81228001);北京呼吸与肺循环疾病重点实验室开放课题(RPCD201201;2011HXFB04);首都医科大学基础临床合作课题(12JL15);北京市教委科技发展计划项目(KM201310025004);宁夏自然科学基金(NZ1220)~~

摘　　要：目的探讨西地那非对低氧下调人肺动脉平滑肌细胞(pulmonary artery smooth muscle cells,PASMCs)电压依赖性钾通道(voltage-dependent potassium channels,Kv)的干预作用。方法应用膜片钳技术记录PASMCs K+电流;观察低氧刺激前后钾离子(K+)电流的变化以及西地那非(sildenafil)的干预作用;通过特异性Kv1.5抗体透析,分析西地那非作用于人PASMCs Kv分子靶点即通道亚单位;运用Real-time PCR及Western blotting技术检测低氧刺激前后及西地那非对人PASMCs上的Kv1.5通道基因转录水平和蛋白表达水平的影响。结果低氧明显抑制了人PASMCs细胞膜上的全细胞K+电流;而西地那非则可以对抗低氧对全细胞K+电流的抑制作用;而且西地那非对低氧下人PASMCs Kv的调控作用靶点主要是Kv1.5;同时西地那非部分恢复了低氧抑制的细胞上的Kv1.5 mRNA和蛋白表达。结论西地那非能够抑制低氧对人肺动脉平滑肌细胞电压依赖性钾通道功能与表达的下调作用。Objective To investigate the effect of sildenafil on hypoxia-induced voltage-dependent potassium channels （Kv） downregulation in human pulmonary artery smooth muscle celIs（PASMCs）. Methods Patch clamp techniques were applied to record K＋ currents from human PASMCs cultured with SMBM （2% FBS） in normoxia or hypoxia（ 3% 02 ） in the absence or presence of sildenafil （100 nM） for 72 h. Furthermore, the effect of sildenafil on the Kv channel subfamily was examined via the special anti-Kv1. 5 antibody dialysis. Real-time PCR and Western blotting techniques were performed to detect the gene transcription and protein expression of Kv1. 5 channel in human PASMCs. Results Hypoxia obviously inhibited whole-cell K＋ currents in PASMCs; sildenafil significantly restored hypoxia-decreased K＋ currents ; Kv1. 5 channel is the target of the modulation of sildenafil on Kv in hypoxic PASMCs ; sildenafil partially restored hypoxia-inhibited mRNA and protein expression of Kv1. 5 channel in PASMCs. Conclusion Sildenafil inhibits hypoxia-induced voltage-dependent potassium channels downregnlation in human PASMCs.

关 键 词：西地那非 电压依赖性钾通道 人肺动脉平滑肌细胞 

分 类 号：R332[医药卫生—人体生理学]