有氧运动对肥胖性高血压大鼠肾素-血管紧张素系统和心功能的改善作用

Improvement effects of aerobic exercise on renin-angiotensin system and cardiac function in obese hypertensive rats

目的:探讨有氧运动对肥胖性高血压(OH)大鼠肾素-血管紧张素系统(RAS)和心功能的影响,阐明有氧运动对OH的保护作用。方法:给予健康雄性SD大鼠高脂饮食12周以诱导OH大鼠模型,将30只成功诱导OH大鼠随机分为安静组(OH+S)和有氧运动组(OH+E),同时将接受普通饮食的30只正常大鼠随机分为安静组(N+S)和有氧运动对照组(N+E),每组15只。OH+E组和N+E组大鼠进行8周跑台运动(18m·min-1,每次60min,每周5次)。监测各组大鼠训练8周后的收缩压(SBP)、体质量、血清肾素、血管紧张素Ⅱ和醛固酮水平,检测血浆甘油三酯(TG)、总胆固醇(TC)、Lee氏指数、脂肪系数(FC)和脂肪含量,同时采用PowerLab数据系统记录各组大鼠左室舒张末期容积(EDV)、左室收缩末期容积(ESV)、短轴缩短率(FS)和射血分数(EF)。结果:OH+E组大鼠训练后的SBP、体质量、血清肾素、血管紧张素Ⅱ和醛固酮水平、血浆TG、TC、Lee氏指数、FC及脂肪含量均低于OH+S组(P<0.05);与OH+S组比较,OH+E组大鼠FS和EF均升高,EDV和ESV均降低(P<0.05);但OH+E组大鼠的上述指标与N+S组和N+E组比较差异仍有统计学意义(P<0.05)。结论:有氧运动可改善OH大鼠的RAS激活并改善心功能,同时改善高血压和肥胖症状。

Objective To observe the influence of aerobic exercise in the renin-angiotensin system（RAS）and cardiac function in the obese hypertension（OH）rats,and to clarify the protective effect of aerobic exercise on OH.Methods The male healthy Sprague-Dawley rats were used to induce rat model of OH by high fat diet.Thirty successfully established OH rats were randomly assigned into sedentary group（OH ＋S）and exercise group（OH＋E）with 15 rats for each group.Meanwhile,30 rats fed with regular diet were randomly assigned into sedentary group（N＋S）and exercise group（N＋E）with 15 rats for each group.The rats in OH＋E group and N＋E group underwent treadmill running at 18m·min^-1（60min each,5times a week）.Eight weeks later,the systolic blood pressure（SBP）,body weight,serum levels of renin,angiotensin Ⅱ and aldosterone of the rats in various groups were measured. Moreover,the obesity related indexes,including triacylglycerol（TG）,total cholesterol（TC）,Lee＇s index and fat coefficient（FC）,and fat weight were recorded.The PowerLab data system was employed to record the cardiac function,such as left ventricular end diastolic volume（EDV）,left ventricular end systolic volume（ESV）,fractional shortening（FS）and ejection fraction（EF）.Results Compared with OH＋S group,the SBP,body weight,serum levels of renin,angiotensinⅡ and aldosterone,obesity related indexes and fat content of the rats in OH＋E group after exercise were decreased（P〈0.05）.The FS and EF of the rats in OH＋E group were increased and the EDV and ESV were decrased compared with OH＋S group（P〈0.05）.However,the above indexes of the rats in OH＋E group were still different from N＋S group and N＋E group（P〈0.05）.Conclusion Aerobic exercise can attenuate the RAS activation and improve cardiac function,also improve the symptoms of hypertension and obesity.