有氧运动对自发性高血压大鼠肾脏纤维化及细胞凋亡的影响

The effects of aerobic exercise on renal fibrosis and apoptosis in spontaneously hypertensive rats

目的观察规律有氧运动对自发性高血压大鼠肾脏纤维化及细胞凋亡的影响。方法采用随机数字表法将30只6周龄雄性自发性高血压大鼠(SHR)分为高血压安静组(简称安静组)及高血压运动组(简称运动组),每组15只。同期选取10只年龄、性别相匹配的Wistar-Kyoto大鼠纳入正常血压对照组(简称正常对照组)。运动组大鼠给予12周游泳运动(每天运动60 min,每周运动5 d),安静组及正常对照组大鼠均在鼠笼内安静饲养。于训练前及末次训练结束后检测各组大鼠尾动脉血压;于末次训练结束后测定各组大鼠24 h尿蛋白、血尿素氮及血清肌酐含量,利用Masson染色观察肾脏间质纤维化程度并计算胶原容积分数(CVF),采用TUNEL染色法记录肾小管上皮组织凋亡细胞数量并计算细胞凋亡率,利用Western blot法检测肾脏转化生长因子β1(TGF-β1)、Smad2/3、Smad7、Bax和Bcl-2蛋白表达量。结果与干预前比较,干预后安静组收缩压、舒张压及平均动脉压均显著升高(P<0.05),运动组收缩压、舒张压及平均动脉压均显著降低(P<0.05),正常对照组血压无明显变化(P>0.05)。与正常对照组比较,干预后安静组血压、24 h尿蛋白、血尿素氮及血清肌酐含量、细胞凋亡率、TGF-β1、Smad2/3和Bax蛋白表达量均明显增加(P<0.05),Smad7及Bcl-2蛋白表达量均明显降低(P<0.05);与安静组比较,干预后运动组大鼠血压、24 h尿蛋白、血尿素氮及血清肌酐含量、细胞凋亡率、TGF-β1、Smad2/3和Bax蛋白表达量均显著下降(P<0.05),Smad7及Bcl-2蛋白表达量均显著增加(P<0.05)。结论规律有氧运动能通过抑制肾脏纤维化及细胞凋亡改善自发性高血压大鼠肾功能障碍。

Objective To explore any effect of regular aerobic exercise on renal fibrosis and apoptosis in rats with spontaneous hypertension.Methods Thirty 6-week-old male spontaneously hypertensive rats were ran-domly divided into a sedentary group(group HS)and an exercise group(group HE).Ten age-and sex-matched Wistar-Kyoto rats formed a control group.The rats in group HE underwent 12 weeks of swimming exercise lasting 60 minutes,five times a week,while the other two groups were kept quiet in their cages.Before and after the training,the tail artery blood pressure of each rat was measured.Renal function was evaluated after the experiment by measuring 24h urine protein,blood urea nitrogen and serum creatinine levels,while the degree of renal interstitial fibrosis was measured using Masson staining and the collagen volume fraction was calculated.The number of apoptotic cells in the renal tubular epithelial tissue was recorded by TUNEL staining and the apoptosis rate was calculated.The expression of renal transforming growth factorβ1(TGF-β1),Smad2/3,Smad7,Bax and Bcl-2 protein were detected using western blotting.Results After the intervention,the average systolic and diastolic blood pressure and mean arterial pressure of group HS had increased significantly,while those of group HE had de-creased significantly,with no significant changes in those measurements among the control group.Compared with the control group,after the intervention,the average blood pressure,24h urinary protein,blood urea nitrogen and serum creatinine,as well as the cell apoptosis rate and expression of TGF-β1,Smad2/3 and Bax had increased sig-nificantly,and that of Smad7 and Bcl-2 had decreased significantly in group HS.And compared with group HS,in group HE the average blood pressure,24h urinary protein,blood urea nitrogen,serum creatinine and the cell apop-tosis rate had decreased significantly,together with the expression of TGF-β1,Smad2/3 and Bax,but the average expression of Smad7 and Bcl-2 had increased significantly.Conclusion Regular aerobic exercise can relieve the renal dysfunction seen in spontaneous hypertension,at least in rats,by inhibiting renal fibrosis and apoptosis.