运动性心肌肥厚细胞微管重组对心功能的影响

Effects of Microtubules Restructuring on Exercise Induced Myocardial Hypertrophy in Rats on Cardiac Function

目的:研究运动性心肌肥厚引起的心肌细胞骨架重组与心功能改变之间的关系。方法:跑台法制备大鼠运动性心肌肥厚模型。大鼠分为正常对照组、训练8周组、训练12周组及训练12周停训8周组;检测各组血流动力学指标评价心功能;测定全心指数、左心指数评价心脏肥厚程度;酶法急性分离技术制备活体单个心肌细胞,免疫荧光法对活细胞的骨架主要成分微管进行染色,在激光共聚焦显微镜下比较重组前后细胞骨架形态的差异,并读取荧光强度对α-微管进行定量测定。结果:与A组比较,B、C两组HMI及LVM增加,HR减慢,LVSP、±dp/dtmax,均有升高,LVEDP降低;B、C两组进行比较,HR、LVSP及LVEDP差异无统计学意义,C组±dp/dtmax高于B组;两组细胞骨架发生了重组,微管数量增多,排列紧密,亮度明显较强,C组微管量高于B组。结论:运动性心肌肥厚引起了心功能的改变,心肌细胞骨架发生重组,重组后的细胞骨架排列紧密,微管含量增加,微管对心肌细胞的弹性强度起负调节作用,而对心肌黏性强度的负调节作用不明显。

objective ： Research the relationship between the changes on exercise myocardial hypertrophy of myocar dial cells caused skeleton restructuring and heart function. Methods ： Run a method manufactured a model of rats exercise myocardial hypertrophy. Rats were divided into normal group, 8 weeks training group, 12 weeks training group and 12 weeks training and 8 weeks suspension group. The researchers detected each hemodynamic for evalu ating heart function, tested the whole heart index, left heart index to evaluate cardiac hypertrophy degree, made live single myocardial cells by enzymatic acute separate technology, dyed the microtubules of the skeleton of living cells by the method of immunofluorescence, compared cytoskeleton shape of differences of cells restructuring be fore and after under the confocal laser microscope, and read fluorescence intensity to measure the a-microtubules quantitatively. Results： Compared with group A, group B and C witnessed increased in HMI and LVM, LVSP, ± dp/dtmaX of and decrease in HR and LVEDP ; the differences about HR, LVS and LVEDP were no statistical signif icance in group B and C, group C were higher than group B in ±dp/dt cytoskeleton happened restructuring in two groups, the number of microtubules had increased, arranged close together, gained stronger brightness. The total of microtubules of group C were higher than B. Conclusions ： Exercise induced myocardial hypertrophy caused the change of heart function. Cytoskeleton of myocardial cells have restructured. Cytoskeleton arranged close to gether after reorganization. Microtubules purity increased. The microtubules had negative regulation effect on the elastic strength of myocardial cells, whereas the negative regulation was unconspicuous on myocardial adhesive strength.