中文摘要：

目的：观察不同强度运动对自发性高血压大鼠（spontaneously hypertensiverat，SHR）肠系膜动脉内皮结构及功能的影响，探讨氧化应激在其中的作用机制。方法：选用3月龄雄性S陬和正常血压大鼠（Wistar Kyoto，WKY）随机分为安静对照组（SHR-C，WKY-C）、中等强度运动组（SHR—M，WKY-M）和高强度运动组（WKY-H，SHR-H）。中等强度运动组以18～20m／min、高强度运动组以26-28m／min进行跑台运动，坡度为0°，60min／天，5天／周。8周运动训练束进行元创尾动脉血压测试、血清氧化应激指标检测、内皮细胞超微结构透射电镜观察及肠系膜动脉微血管张力测定。结果：1）SHR-M的收缩压和舒张压显著低于SHR-C（P〈0．05），而SHR-H显著高于SHR-C（P〈0．05）。2）血清氧化产物丙二醛（MDA）检测显示：SHR—C组血清MDA含量与WKY-C相比，均值有升高趋势但不具有统计学差异（P〉0．05），SHR-M组MDA含量与SHR—C不具有显著性差异（P〉0．05），但SHR-H血清MDA含量显著高于SHR-C（P〈0．05）；抗氧化物酶谷胱甘肽过氧化物酶（GSH—Px）、过氧化物歧化酶（SOD）检测显示：SHR—CGSH—Px酶活力显著低于WKY-C组（P〈0．05），SHR—M组和SHR—H组GSH—Px酶活力显著高于SHR-C（P〈0．05）。WKY-M SOD显著高于WKY-C（P〈0．05），SHR运动组与SHR安静组相比较SOD无统计学差异（P〉0．05）。3）透射电镜结果显示：SHR-C和SHR-H组均表现为内皮细胞畸形、胶原纤维增生，而SHR-M血管内皮细胞形态完整。4）微血管张力测定结果显示：SHR-C内皮依赖性血管舒张能力显著小于WKY-C，SHR-M内皮依赖性血管舒张能力显著高于SHR-C，而SHR-H显著低于SHR-M（P〈0．05）。结论：中等强度运动训练可以降低高血压大鼠血压、改善内皮结构和功能，其机捌可能与运动降低氧化应激水平相关。然而，高强度运动则上调氧化应激水平，加

英文摘要：

Objective： To investigate the effects of treadmill exercise with different intensity on spontaneously hypertensive rats＇ endothelial function and ultrastructure. Methods. Three- month-old male SHR and WKY were randomly assigned to six groups, sedentary control group （SHR-C, WKY-C）, moderate-intensity exercise group （ SHR-M, WKY-M）, and high-intensity exercise group （SHR-H, SHR-H）. The animals in the exercise-trained groups ran on a motor treadmill （0° slope） at 18-20 m/min （-55-65% of the maximal aerobic velocity） and 26-28m/min （- 75- 85% of the maximal aerobic velocity）, respectively. Each exercisetrained group ran 60 rain per day, 5 days per week for 8 weeks. Blood pressure examined by non-invasive methods, endothelial ultrastrueture observed by transmission electron microscope, tension test to isolated vessel ring measured by DMT, protein determined by western blotting and detection for enzyme activity. Result. 1）Systolic pressureand diastolic pressure in SHR-M were much lower than in SHR-C, and SHR-H significantly different from SHR-C（P〈0. 05）. 2）Oxidative product MDA demonstrated that compared to MDA in WKY-C,SHR-C had the trend to rise,but no significant difference. SHR-H were significantly higher than SHR-M （P 〈0. 05）. Antioxidant enzymes including GSH-Px, SOD demonstrated that GSH-Px in SHR-C were lower in comparison with WKY-C,GSH-Px in SHR-H and SHR-M were significantly higher compared to SHR-C （P〈0. 05）; SOD in WKY-M were significantly higher than in WKY-C （P〈0. 05）,SOD in SHR exercise-trained groups had no significant difference compared to SHR-C（P〈0. 05）. 3） Transmission electron mieroscope in SHR-C and SHR-H showed that endothelial cells＇ malformation, collagen proliferation. However, SHR-M showed the intact of endothelial cells. 4）Endothelial-dependent vasodilator function in SHR-C was strikingly lower in comparison with WKY-C,SHR-M ameliorated endothetium-dependent dilation dysfunction induced by hypertension; However, endotheli