运动训练改善高血压大鼠动脉压力反射功能  

Exercise training improves the arterial baroreflex function in hypertensive rats

作　　者：党娜[1] 黄秀珍[2] 林诚[2] 潘燕霞[2] 

机构地区：[1]福鼎市医院神经内科,福建福鼎355200 [2]福建医科大学医学技术与工程学院康复治疗学系

出　　处：《中华高血压杂志》2015年第1期47-51,共5页Chinese Journal of Hypertension

基　　金：国家自然科学基金项目(81372111);福建医科大学教授基金(JS09001)

摘　　要：目的观察运动训练对高血压大鼠动脉压力反射和中枢氧化应激的影响,探讨运动训练改善压力反射功能的中枢机制。方法雄性自发性高血压大鼠(SHR)20只和正常血压Wistar大鼠24只随机分成对照组和运动训练组,运动组大鼠进行8周跑台运动。尾套法测定大鼠收缩压和心率,静脉注射苯肾上腺素(PE)和硝普钠检测动脉压力反射敏感性(BRS)。侧脑室给予超氧化物歧化酶(SOD)拟似剂Tempol和SOD抑制剂DETC,测定给药前后BRS变化。下丘脑丙二醛含量、总抗氧化能力(T-AOC)以及抗氧化酶SOD与过氧化氢酶(CAT)活性用于评估氧化应激。结果运动前,SHR收缩压明显高于Wistar大鼠(P<0.01)。运动训练显著降低SHR和Wistar大鼠心率,但仅降低SHR收缩压。SHR的BRS明显小于Wistar大鼠[PE:(0.89±0.22)比(1.96±0.23)次/(min·mm Hg);硝普钠:(0.62±0.10)比(1.32±0.23)次/(min·mm Hg),均P<0.01]。运动训练明显改善SHR的BRS,与SHR对照组相比,SHR运动组BRS明显提高[PE:(1.31±0.26)比(0.89±0.22)次/(min·mm Hg);硝普钠:(1.22±0.25)比(0.62±0.10)次/(min·mm Hg);均P<0.05]。侧脑室给予DETC抵消运动训练改善SHR之BRS的作用(P<0.05),并降低Wistar大鼠BRS(P<0.05),而Tempol则改善SHR的BRS(P<0.05),使SHR运动组大鼠BRS正常化。运动训练使SHR下丘脑丙二醛含量降低27%(P<0.05),同时使下丘脑T-AOC、SOD和CAT活性分别增加74%、41%和62%(P<0.05);运动训练使Wistar大鼠下丘脑丙二醛含量降低40%(P<0.05),并使下丘脑T-AOC、SOD和CAT活性分别增加72%、30%和51%(P<0.05)。结论中枢氧化应激抑制动脉压力反射,运动训练通过增强脑内抗氧化酶活性和抗氧化能力降低中枢氧化应激,从而改善高血压大鼠动脉压力反射功能。Objective To investigate the influence of exercise training on arterial baroreflex and its central mecha- nisms in spontaneously hypertensive rats （SHR）. Methods Twenty male SHR and 24 normotensive Wistar rats were randomly assigned into control group or exercise training group. Exercise training was performed on a tread- mill for 8 weeks. Systolic blood pressure （SBP） and heart rate were measured by tail-cuff method. Baroreflex sensitivity （BRS） was determined by intravenous injection of phenylephrine （PE） and sodium nitroprusside. Alterations in the BRS were evaluated before and after intracerebroventricular administration of superoxide dismutase （SOD） mimetic Tempol or SOD inhibitor DETC. Malondialdehyde （MDA） content, total antioxidant capacity （T-AOC）, SOD and catalase （CAT） antioxidant enzyme activities in the hypothalamus were measured to assess oxi- dative state. Results Before exercise training, SBP in two groups of SHR was obviously higher than in those of normotensive Wistar rats （P〈0.01）. Exercise training significantly decreased heart rate in both SHR and Wistar rats, and SBP in SHR alone. The BRS of SHR in control group was significantly lower than that of normotensive Wistar rats [PE： （0.89±0.22） vs （1.96±0.23）beats/（min·mm Hg）; sodium nitroprusside： （0.62±0.10） vs （1.32±0.23）beats/（min ·mm Hg）, both P〈0. 013. Exercise training significantly improved the BRS of SHR. Compared with SHR in control group, the BRS in trained SHR was significantly increased [PE： （1.31±0.26） vs （0.89±0.22）beats/（min·mm Hg） ; sodium nitroprusside： （1.22±0.25） vs （0.62±0.10）beats/（min ·mm Hg）, both P〈0. 01]. Intraeerebroventrieular infusion of DETC abolished the beneficial effect of exercise training on BRS in SHR （P〈0.05} and significantly decreased BRS in two Wistar groups （P〈0. 05）. In contrast, Tempol greatlyimproved BRS in two SHR groups {P〈0.05） and normalized BRS in trained SHR. Exercise trainin

关 键 词：高血压 运动训练 动脉压力反射 中枢神经系统 氧化应激 

分 类 号：R87[医药卫生—运动医学]