有氧运动训练8周可改善肥胖介导大鼠肠系膜动脉平滑肌电压依赖性钾通道功能  

An 8-week aerobic exercise promotes the function of voltage-dependent potassium channel in mesenteric vascular smooth muscle from obese rats

作　　者：李梓涵 印文 孙薇 朱坤 沈娣 刘雨佳 Li Zihan;Yin Wen;Sun Wei;Zhu Kun;Shen Di;Liu Yujia(School of Physical Education,Jiangsu Normal University,Xuzhou 221116,Jiangsu Province,China)

机构地区：[1]江苏师范大学体育学院,江苏省徐州市221116

出　　处：《中国组织工程研究》2021年第17期2630-2635,共6页Chinese Journal of Tissue Engineering Research

基　　金：江苏省自然科学基金(BK20190999),项目负责人:刘雨佳;江苏省高校自然科学基金(18KJB180003),项目负责人:刘雨佳;江苏省大学生创新创业一般项目(201910320142Y),项目负责人:李梓涵。

摘　　要：背景:血管平滑肌细胞上的K~+通道在调节血管舒张过程中起到重要作用。有氧运动作为减轻肥胖的非药理学方式可调节血管平滑肌K~+通道,而有氧运动能否改善肥胖诱导的血管平滑肌K~+通道的功能和表达尚未见研究。目的:探究8周有氧运动训练对肥胖大鼠肠系膜动脉平滑肌K~+通道的作用。方法:选择8周龄雄性SD大鼠60只,20只普通饲料喂养,其余40只采用高脂喂养构建肥胖模型,筛选得到20只肥胖大鼠。肥胖大鼠和正常大鼠均随机分为正常安静组、正常运动组、肥胖安静组和肥胖运动组,每组10只。所有大鼠均进行1周动物跑台适应性训练后,正常运动组和肥胖运动组大鼠进行8周跑台有氧运动训练,训练方案为:0°,20 m/min,60 min/d,5 d/周。在最后一次运动48 h后,采集静脉血检测大鼠血脂和血糖水平;取肠系膜动脉,一部分制成4 mm左右血管环,连于张力换能器,检验血管张力及对电压依赖性钾通道特异性阻断剂4-氨基吡啶和大电导钙激活钾通道特异性阻断剂北非蝎毒素的反应性,另一部分采用Western blot方法测定Kv1.2、Kv1.5、BK_(Ca)α亚基和BK_(Ca)β1亚基的蛋白表达水平。结果与结论:①肥胖运动组体质量、心脏质量、空腹血糖、三酰甘油和低密度脂蛋白水平较肥胖安静组非常显著降低(P <0.01);②各组大鼠肠系膜动脉对KCl的反应性差异无显著性意义(P> 0.05);③正常运动组在4-氨基吡啶刺激后张力显著高于正常安静组(P <0.05);肥胖安静组与正常安静组相比张力幅值显著降低(P <0.05);而肥胖运动组对4-氨基吡啶的反应性显著高于肥胖安静组(P <0.05);④正常运动组对北非蝎毒素的反应性显著高于正常安静组(P <0.05),但是肥胖安静组与正常安静组差异无显著性意义(P> 0.05);⑤肥胖安静组Kv1.2蛋白表达显著低于正常安静组(P <0.05),而肥胖运动组Kv1.2蛋白表达较肥胖安静组显著增加(P <0.05);正常BACKGROUND:K+channels in vascular smooth muscle cells play an important role in regulating vasodilation.Aerobic exercise that acts as a nonpharmacological way for weight loss can regulate vascular smooth muscle K+channels.Whether aerobic exercise can improve the function and expression of obesity-induced vascular smooth muscle K+channels has not been elucidated.OBJECTIVE:To investigate the effects of 8-week aerobic exercise on the K+channel of mesenteric vascular smooth muscle in obese rats.METHODS:Sixty Sprague-Dawley rats(8 weeks old,male)were used in this study,20 of which were fed with normal feed,and the other 40 were fed with high fat diet to induce obesity.Twenty obese rats were then obtained.Obese rats were randomized into an obese control group and an obese exercise group;normal rats were randomized into a normal control group and a normal exercise group,with 10 rats in each group.After all rats were adaptively trained for 1 week on the running platform,and those in the normal exercise and obese exercise group were then trained for another 8 weeks.The training plan was:0°,20 m/min,60 min/d,5 days a week.All rats were anesthetized and sacrificed 48 hours after the last exercise,and venous blood samples were extracted to measure blood sugar and blood lipid levels.Mesenteric artery was taken,a part of which was made into a vascular ring of about 4 mm that was connected to a tension transducer to test the vascular tension and reactivity of the vessel to the voltage-dependent potassium channel(Kv)specific blocker 4-aminopyridine and large-conductance calcium-activated potassium channel(BKCa)specific blocker charybdotoxin,and the other part of which was used to test the levels of Kv1.2,Kv1.5,BKCaαsubunit and BKCaβ1 subunit by western blot.RESULTS AND CONCLUSION:(1)Body mass,heart weight,fasting blood glucose,triglyceride,low-density lipoprotein and total cholesterol in the obese exercise group were significantly lower than those in the obese control group(P<0.01).(2)There was no significant difference in th

关 键 词：肥胖 钾通道 电压依赖性 大电导钙激活 有氧运动 大鼠 实验 

分 类 号：R455[医药卫生—运动医学] R318[医药卫生—治疗学]