摘要
目的:探讨心脏β3-AR及其下游分子eNOS和nNOS的变化是否在有氧运动保护心肌梗死后心功能中发挥作用。方法:选取雄性SD大鼠48只,随机分为正常对照组(C),心肌梗死组(MI),心梗+中强度持续有氧运动组(ME1),心梗+高强度间歇有氧运动组(ME2),每组12只。C组大鼠常规饲养,MI组采用心脏左冠状动脉前降支(LAD)结扎法,建立MI模型。ME1和ME2组大鼠在MI手术后一周进行8周跑台运动。ME1组运动以10m/min速度,运动5min后,以3m/min的速度递增至16m/min。ME2组运动以10m/min速度,运动10min后,速度逐渐递增至25m/min,运动7min;然后间歇3min,其速度为15m/min,之后依次交替进行。ME1和ME2组运动总时间均为60 min,5d/1wk×8wk。训练结束后,测定LVSP、LVEDP、±dp/dtmax指标,判定各组大鼠心功能变化。之后开胸摘取心脏,进行组织学制片,Masson染色。免疫荧光法观察分析左心室β3-AR表达。Western Blot法检测β3-AR、eNOS及nNOS蛋白含量。结果:与C组相比,MI组胶原容积百分比(CVF)和LVEDP显著升高(P<0.01),LVSP和-dP/dt max均显著降低(P<0.05)。MI后可见左心室β3-AR阳性染色,位于心肌细胞膜表面。同时β3-AR蛋白表达有增高趋势。左心室eNOS蛋白表达有下降趋势,nNOS表达显著增加(P<0.01)。与MI组比较,ME1和ME2组CVF和LVEDP均显著降低(P<0.01),ME1组-dP/dt max显著升高(P<0.05),ME2组LVSP显著增加(P<0.05)。ME1和ME2组均可见左心室β3-AR阳性染色,同时ME1组β3-AR蛋白表达显著增加(P<0.05)。ME2组β3-AR表达有增加趋势。ME1和ME2组eNOS和nNOS表达较MI组均显著增加(P<0.05,P<0.01)。而ME1和ME2组各指标均无显著差异。结论:中强度持续有氧运动和高强度间歇有氧运动两种运动方式均可通过增加左心室β3-AR表征,上调其下游因子eNOS及nNOS蛋白表达,抑制心梗后胶原过度增生,保护心梗大鼠心功能。
Obiectives：To discuss the effect of aerobic exercise on beta3-adrenoreceptor and ni- tric oxide synthase in left ventricular after myocardial infarction. Methods： 48 male Sprague- Dawley rats were randomly assigned to four groups （n= 12） ： control group （C）, myocardial infarction group （MI）, moderate-intensity aerobic exercise with myocardial infarction group （ME1）, high-intensity aerobic interval exercise with myocardial infarction group （ME2）. MI was induced by ligation of the left anterior descending （LAD） coronary artery. ME1 and ME2 group rats started exercising at 1 week post-MI using a motorized rodent treadmill. Exercise in ME1 group was initiated at 10 m/min, for 5 min. The speed were gradually increased to 16 m/min. Exercise in ME2 group was initiated at 10 m/min, for 10 min. Exercise intervals alter- nated between 7 min at 26 m/min of speed and 3 min at 15 m/min of speed, total time was 60 min. The exercise was performed 5 days per week for 8 weeks. After tmining, the following hemodynamic parameters were measured to detect cardiac function ： LVSP, LVEDP, ±dp/dt- max. Then the heart was taken for histologic section and Masson dyeing.β3-AR in the left ventricle was examined by immunofluoresence staining and Western blot. eNOS and nNOS were examined by Western blot. Results： MI increased CVF and LVEDP （P〈0.01）, but decreased LVSP and -dp/dtmax （P〈0. 05）. β3-AR-positive cells were identified in the LV, and ex- pressed on the myocardial cell membranes. After MI, β3-AR protein expression in the LV didnot differ but the trend was toward higher, nNOS expression was increased （P〈0.01）, but eNOS was reduced. Compared with MI group, 8-weeks aerobic exercise significantly reduced CVF and LVEDP（P（0. 01）,-dp/dtmax was increased in ME1 group （P〈0. 05）, and LVSP was increased in ME2 group （P〈0.05）. β3-AR protein expression in the LV was in creased in ME1 group （P〈0.05）, and did not differ but the trend was toward higher in ME2 group, eNO
出处
《体育科学》
CSSCI
北大核心
2013年第9期57-63,76,共8页
China Sport Science
基金
国家自然科学基金项目(31040045,31171141)
陕西师范大学“211工程”-运动生物学重点建设学科项目(2012-11)
关键词
Β3-AR
中强度持续有氧运动
高强度间歇有氧运动
心肌梗死
一氧化氮合酶
鼠
动物实验
beta3 -adrenoreceptor
moderate-intensity aerobic exercise
high-intensity aerobic interval exercise
myocardial infarction
nitric oxide synthase
rat
animal experimant
