异莲心碱对小鼠离体气管平滑肌的舒张作用  

Relaxation effect of isoliensinine on isolated mouse airway smooth muscle

作　　者：刘贝贝 陈微微 张雯婧 刘庆华 LIU Bei-bei;CHEN Wei-wei;ZHANG Wen-jing;LIU Qing-hua(College of Life Sciences,South-Central University for Nationalities,Institute of Medical Biology & Hubei Provincial Key Laboratory for Protection and Application of Special Plant Germplasm in Wuling Area of China,Wuhan 430074,China)

机构地区：[1]中南民族大学生命科学学院医学生物研究所&武陵山区特色资源植物种质保护与利用湖北省重点实验室,湖北武汉430074

出　　处：《中国病理生理杂志》2019年第5期920-925,共6页Chinese Journal of Pathophysiology

基　　金：国家自然科学基金资助项目(No.81400015; No.31571200);湖北省自然科学基金资助项目(No.2013CFB455);2019年度中央高校基本科研业务费专项资金资助项目(No.CZY19017)

摘　　要：目的:研究异莲心碱对高K^+预收缩小鼠离体气管平滑肌(ASM)的舒张作用及其机制。方法:利用张力换能器检测异莲心碱对高K^+诱导的ASM预收缩和Ca^(2+)内流的影响;利用膜片钳技术和钙成像系统分别检测异莲心碱对ASM细胞膜L型电压依赖性Ca^(2+)通道(LVDCC)电流以及细胞内Ca^(2+)浓度([Ca^(2+)]_i)的影响。结果:异莲心碱可显著舒张高K^+预收缩的ASM,且其舒张作用呈现浓度依赖性,当浓度为100μmol/L时最大舒张比达到(95.3±3.9)%。此外,利用膜片钳全细胞记录技术测量LVDCC电流,电流可被异莲心碱完全阻断;在高K^+诱导下气管平滑肌细胞中Fura-2的340/380 nm荧光比值稳定在0.63±0.10,而异莲心碱加入后比值显著下降至0.36±0.05(P<0.01);在[Ca^(2+)]_i峰点加入异莲心碱,340/380 nm荧光比值从0.74±0.02迅速降至0.42±0.05(P<0.01);异莲心碱抑制高K^+诱导的Ca^(2+)内流引起的ASM收缩。结论:异莲心碱可阻断小鼠离体气管平滑肌细胞LVDCC电流,LVDCC介导的Ca^(2+)内流停止,[Ca^(2+)]_i降低,导致ASM舒张,提示异莲心碱可能是潜在的气管舒张剂。AIM:To study the relaxation effect of isoliensinine on high K+-induced isolated mouse airway smooth muscle(ASM)and the underlying mechanism.METHODS:The muscle tension transducer was used to detect the effects of isoliensinine on high K+-induced precontraction and Ca^2+influx in ASM.The technique of patch-clamp and calcium imaging system were respectively used to examine the effects of isoliensinine on LVDCC currents and[Ca^2+]i of the ASM cells(ASMCs).RESULTS:Isoliensinine significantly relaxed precontracted ASM induced by high K+in a concentration-dependent manner.The maximum relaxation ratio was(95.3±3.9)%by isoliensinine at 100μmol/L.In addition,LVDCC currents were measured using the whole-cell patch-clamp technique,which were abolished by isoliensinine.High K+-induced 340/380 nm fluorescence ratio of Fura-2 was 0.63±0.10 in ASMCs,while it decreased to 0.36±0.05 after the addition of isoliensinine(P<0.01).When isoliensinine was added at the peak point of[Ca^2+]i,the ratio rapidly decreased from 0.74±0.02 to 0.42±0.05(P<0.01).Moreover,isoliensinine inhibited high K+-induced Ca^2+influx-mediated contraction of ASM.CONCLUSION:Isoliensinine inhibits LVDCC currents,terminates Ca^2+influx and reduces[Ca^2+]i,eventually resulting in relaxation of the ASM,indicating isoliensinine might be a potential bronchodilator.

关 键 词：异莲心碱 气管平滑肌 L型电压依赖性Ca^2+通道 舒张 

分 类 号：R363.2[医药卫生—病理学] R562.25[医药卫生—基础医学]