早期运动训练用于预防高血压大鼠心功能降低及心肌肥厚的研究  

Early exercise training prevents reduction of cardiac function and cardiac hypertrophy in hypertensive rats

作　　者：洪玲[1] 赵晓霖 陈秀云[1] 林诚[1] 潘燕霞[1] 

机构地区：[1]福建医科大学医学技术与工程学院康复系,福州350004

出　　处：《中国康复医学杂志》2017年第2期161-166,共6页Chinese Journal of Rehabilitation Medicine

基　　金：国家自然科学基金资助项目(81372111);福建省自然科学基金资助项目(2014J01339)

摘　　要：目的:观察高血压前期运动训练对自发性高血压大鼠血压、心功能、心脏质量和心肌肾素-血管紧张素系统影响,探讨运动训练改善心功能和心肌肥厚的作用机制。方法:5周龄雄性自发性高血压大鼠(SHR)和正常血压大鼠(WKY)随机分成安静组(S)和运动训练组(E),4组大鼠分别为:SHR-S,SHR-E,WKY-S和WKY-E,每组10只。运动组进行8周中低强度的跑台运动(60min/d,18—20m/s,5d/周)。尾套法测定大鼠收缩压(SBP),心室插管检测左室舒张末压(LVEDP)、左室压力最大上升和下降速率(±dp/dt max)。左心室质量指数(LVMI)反映心肌肥厚程度。Real-time PCR检测左室心肌血管紧张素转换酶(ACE)和血管紧张素Ⅱ1型(AT1)受体m RNA表达,Western blot分析ACE蛋白水平,ELISA法检测血管紧张素Ⅱ(AngⅡ)水平。结果:运动前,5周龄SHR大鼠SBP与正常WKY无明显差异。运动训练结束,与WKY-S组相比,SHR-S组SBP、LVEDP和LVMI均显著升高(P<0.01),-dp/dt max则明显减慢(P<0.01)。SHR-S组左室心肌ACE、AT1 mRNA表达、ACE蛋白和AngⅡ水平均较WKY-S组明显升高(P<0.01)。SHR-E组SBP、LVEDP和LVMI较SHR-S组明显降低(P<0.01),-dp/dt max则明显高于SHR-S组(P<0.05)。SHR-E组左室心肌ACE、AT1mRNA表达、ACE蛋白和AngⅡ水平较SHR-S组均明显改善(P<0.01)。WKY-E组SBP、LVEDP、LVMI、±dp/dt max等指标与WKY-S组比较呈轻度改变,但均未达到显著性意义,WKY-E组左室心肌ACE、AT1mRNA表达、ACE蛋白和AngⅡ水平与WKY-S组无显著差别。结论:高血压前期运动训练延缓SHR大鼠高血压进展、预防心脏舒张功能降低和心肌肥厚,其机制可能与运动训练抑制心脏过度激活的ACE-AngⅡ-AT1轴的作用有关。Objective：To observe the effects of exercise training at the prehypertensive stage on blood pressure, cardiac function and mass as well as renin-angtiotensin system in the left ventricle and to investigate its mechanisms by which exercise training improves cardiac function and hypertrophy in the spontaneously hypertensive rats（SHR）.Method：Male 5-wk old SHR and normotensive WKY rats were randomly divided into sedentary（S） and exercise training（E） groups, consisting of 4 groups as ： SHR-S,SHR-E,WKY-S and WKY-E,n=10 for each group.The trained rats ran on a treadmill with low-to-moderate intensity for 8 weeks（60min/d,18—20m/s, 5d/wk）.Systolic blood pressure（SBP） was measured by a tail-cuff method. The left ventricular end-diastolic pressure（LVEDP）, the maximal increase and decrease velocity of left ventricular pressure（± dp/dt max）were recorded through the left ventricular cannula. The left ventricular mass index（LVMI） was assessed to represent cardiac hypertrophy. The mRNA expression of angiotensin converting enzyme（ACE） and angiotensinⅡ 1 type receptors（AT1） in the left ventricular myocardium were detected by real-time PCR and the protein level of ACE was determined by Western blot. The Cardiac AngⅡwas assayed by ELISA。Result：Before exercise, there were no significant difference in systolic blood pressure between 5-wk SHR and age-matched WKY. At the end of exercise training, SBP,LVEDP and LVMI were significantly increased, but-dp/dt max was decreased in the SHR-S group compared with WKY-S rats（P〈0.01）. The mRNA expression of ACE and AT1, protein expression of ACE and AngⅡ level in the left ventricle myocardium were significantly increased in the SHR-S group compared with the WKY-S group（P〈0.01）. However, SBP, LVEDP and LVMI were significantly lower in the SHR-E group than those in the SHR-S group（P〈0.01）, but-dp/dt max was higher in the SHR-E group than that in the SHR-S group（P〈0.05）. The mRNA expression of ACE and AT1,ACE protein e

关 键 词：高血压前期 运动训练 心功能 肾素-血管紧张素系统 

分 类 号：R544.1[医药卫生—心血管疾病]