AKAP150/PKCα在有氧运动改善高血压脑动脉CaV1.2通道功能中的作用  

Roles of AKAP150/PKCαin Aerobic Exercise-Improved CaV1.2 Channel Function of Cerebral Arteries in Hypertension

作　　者：张严焱 单美玲 徐召霞 陈渝[1] 周杨 邱方[1] 张琳[1] 石丽君[1,2] ZHANG Yan-yan;SHAN Mei-ling;XU Zhao-xia;CHEN Yu;ZHOU Yang;QIU Fang;ZHANG Lin;SHI Li-jun(Department of Sports Physiology,Beijing Sport University,Beijing 100084,China;Key Laboratory of Sports And Physical Health of Ministry of Education,Beijing Sport University,Beijing 100084,China)

机构地区：[1]北京体育大学运动生理教研室,北京100084 [2]北京体育大学运动与体质健康教育部重点实验室,北京100084

出　　处：《北京体育大学学报》2020年第8期97-110,共14页Journal of Beijing Sport University

基　　金：国家自然科学基金项目(项目编号:31771312);中央高校基本科研业务费专项资金资助(项目编号:2020049)。

摘　　要：目的:探讨AKAP150/蛋白激酶Cα(PKCα)途径在有氧运动调控高血压脑动脉平滑肌L型电压门控钙通道(L-type CaV1.2 channel,CaV1.2)功能中的作用及机制。方法:12周龄雄性自发性高血压大鼠(Spontaneously hypertensive rat,SHR)及正常血压大鼠(Wistar-Kyoto,WKY)随机分为正常血压安静组(WKY-SED),正常血压运动组(WKY-EX),高血压安静组(SHR-SED)和高血压运动组(SHR-EX);运动组进行中等强度跑台运动训练。12周后,取脑动脉,分别采用免疫蛋白印迹,免疫荧光,膜片钳全细胞、单通道记录模式,qPCR技术观察脑动脉平滑肌AKAP150/PKCα信号途径变化,CaV1.2通道全细胞、单通道电流,CaV1.2α1c亚基mRNA、蛋白表达。构建AKAP150基因平滑肌条件性过表达敲入模式鼠(AKAP150 smKI),植入式生理信号无线遥测系统监测清醒自由活动下敲入小鼠血压变化。结果:1)有氧运动可显著降低SHR-EX组大鼠体重和血压。2)脑动脉血管平滑肌AKAP150蛋白表达在SHR-SED组显著上调,SHR-EX组表达下调;PKCα蛋白表达在各组间无显著差异,但与SHR-SED相比,SHR-EX组脑动脉平滑肌细胞PKCα膜转运显著下降。3)有氧运动显著降低SHR-EX组脑动脉平滑肌细胞AKAP150与PKCα共定位比率。4)有氧运动显著抑制SHR脑动脉平滑肌CaV1.2全细胞电流密度的上调;而CaV1.2通道α1c亚基mRNA、蛋白表达水平在各组间无显著差异。5)有氧运动显著降低SHR-EX脑动脉平滑肌细胞CaV1.2单通道开放概率nPo。6)PKCα特异性抑制剂G96976能够分别抑制WKY-SED、WKY-EX、SHR-SED和SHR-EX组脑动脉平滑肌CaV1.2通道全细胞电流31%,35%,48%和38%左右。7)PKC激动剂PDBu使WKY-SED组脑动脉平滑肌CaV1.2单通道nPo增加约1.5倍,SHR-SED组增加约3.8倍,有氧运动抑制了SHR-EX组PDBu引起的CaV1.2通道开放概率的增加。8)与同龄野生型小鼠相比,AKAP150 smKI小鼠收缩压、舒张压和平均动脉压均显著升高。结论:有氧运动可有效降低自发性高血压大鼠Objective:To investigate the roles and mechanisms of AKAP150/protein kinase Cα(PKCα)signaling pathway in aerobic exercise-mediated regulation of L-type CaV1.2 channel(CaV1.2)function in cerebral arteries during hypertension.Methods:12-week-old male spontaneously hypertensive rats(SHR)and Wistar-Kyoto(WKY)rats were randomly assigned to sedentary(WKY-SED,SHR-SED)and exercise training(WKY-EX,SHR-EX)groups,respectively.Exercise groups were performed a moderate-intensity treadmill running.After 12 weeks,Western blot,immunofluorescence,patch-clamp whole-cell and single channel recording,qPCR were used to detect AKAP150/PKCα signaling pathway,CaV1.2 whole-cell and single channel currents,mRNA and protein expression ofα1 c subunits.AKAP150 smooth muscle-specific knockin mice(AKAP150 smKI)were constructed.The blood pressure was monitored in conscious WT and AKAP150 smKI mice using an implantable mouse telemetry system.Results:1)Aerobic exercise significantly reduced body weight and blood pressure in SHR-EX.2)The protein expression of AKAP150 in cerebral arterial smooth muscle was significantly up-regulated in SHR-SED,while down-regulated in SHR-EX.The protein expression of PKCα did not change in four groups,however,sarcolemmal PKCαtranslocation was significantly reduced in SHR-EX as compared with SHR-SED myocytes.3)Aerobic exercise significantly decreased the colocalization rate of AKAP150 and PKCαin cerebral arterial myocytes from SHR-EX.4)Aerobic exercise significantly inhibited SHR-induced increases in CaV1.2 currents in cerebral arterial myocytes,whereas the mRNA and protein expression of α1 c subunits were unchanged.5)Aerobic exercise significantly attenuated the CaV1.2 channel nPo of SHR-EX cerebral arterial myocytes.6)Inhibition of PKCα with G96976 decreased the CaV1.2 currents nearly 31%,35%,48% and 38% in WKY-SED,WKY-EX,SHR-SED and SHR-EX myocytes.7)Application of the PKC activator PDBu increased a^1.5-fold and 3.8-fold in the CaV1.2 channel nPo of WKY-SED and SHR-SED,respectively.Aerobic exercise signif

关 键 词：有氧运动 脑动脉 AKAP150 L型钙通道 

分 类 号：G804.2[文化科学—运动人体科学]