Objective :Exercise can be considered as a simple and effective non‐drug treatment of hypertension .Choosing appropriate intensity and volume is supposed to be of great importance . L‐type Ca2+ (CaV 1 .2) channels on the plasma membrane of vascular smooth muscle cells play a key role in modulating vascular tone .CaV 1 .2 channels upregulation is an ionic feature of hy‐pertension .This study aimed to explore the effects of different intensity of exercise on CaV 1 .2 channel remodeling of mesenteric artery (MA ) from SHR .Methods :Twelve‐week‐old male SHR rats were randomly divided into SHR sedentary group (SHR‐SED ,n=18) ,SHR Moder‐ate‐(SHR‐M ,n= 18 ,18~20 m/min) and high‐intensity (SHR‐H ,n= 18 ,26~28 m/min) of exercise training exercise group .Eighteen age‐matched WKY rats were used as normotensive control .Mesenteric arterial mechanical and functional properties were evaluated .Results :Mod‐erate‐intensity of exercise training induced lower systolic blood pressure and heart rate than those of SHR‐SED .Moderate‐intensity of exercise training significantly suppressed tissue sen‐sitivity to nifedipine ,CaV 1 .2 channel currents density ,and CaV 1 .2‐α1C subunit protein ex‐pression in MAs .However ,high‐intensity of exercise aggravated all of these hypertension‐as‐sociated functional and molecular alterations of CaV 1 .2 channel .Conclusion :Remodeling of MAs contributes to the development and complications of hypertension .The moderate‐intensity exercise can effectively reverse the remodeling of CaV 1 .2 channels in mesenteric artery ,w hich has a positive effect on improving vascular function .High‐intensity exercise would exaggerate the adverse remodeling of CaV 1 .2 channel which impairs vascular function further .%目的：运动是一种简单、有效的高血压非药物辅助疗法，选择适宜的运动强度和运动量是十分重要的。位于 VSMC细胞质膜上的 L 型钙通道（CaV 1．2）对血管紧张度的调节具有关键作用，CaV 1．2通道表达上调是高血压的标志特征。旨在探讨不同强度运动对自发性高血压大鼠（SHR）肠系膜动脉CaV 1．2通道重构的影响。方法：54只SHR大鼠随机分为安静对照组（SHR‐SED ，n＝18）、中等强度运动组（SHR‐M ，18～20 m／min ，n＝18）和大强度运动组（SHR‐H ，26～28 m／min ，n＝18），运动组进行8周跑台运动（1 h／d ，5 d／周）。另选用同龄Wistar‐Kyoto大鼠（WKY ）18只作为安静正常血压对照组。观察不同强度运动对肠系膜动脉舒缩特性、CaV 1．2通道功能和蛋白表达的影响。结果：1）大鼠安静时收缩压和心率：SHR‐SED组显著高于 WKY 组，SHR‐M 组较 SHR‐SED 组显著降低，而 SHR‐H 组明显升高；2）硝苯吡啶（CaV 1．2通道阻断剂）诱发了大鼠肠系膜动脉剂量依赖性的血管舒张，各组大鼠对硝苯吡啶的敏感性依次为：SHR‐H ＞ SHR‐SED ＞ SHR‐M ＞ WKY ，中等强度运动使SHR肠系膜动脉对硝苯吡啶的敏感性明显减弱，相反，大强度运动使其明显增强；3）SHR‐SED组肠系膜动脉平滑肌CaV 1．2通道电流和CaV 1．2通道α1c亚基的蛋白表达均高于WKY组，与SHR‐SED组相比，SHR‐M 组CaV 1．2通道电流和CaV 1．2通道α1c亚基的蛋白表达降低，而SHR‐H组显著增加。结论：高血压可引起肠系膜动脉平滑肌细胞 CaV 1．2通道功能和蛋白表达上调；中等强度的有氧运动能有效逆转高血压动脉 C aV 1．2通道的重构，对改善血管功能具有积极作用，而大强度运动通过加重C aV 1．2通道的不良重构进一步损害血管功能。
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