运动性与病理性心肌肥大左室肌球蛋白α和β重链变化比较

Myosin Isoenzymic Changes Between Physiological and Pathological Cardiac Hypertrophy in Rats

对大鼠运动心肌肥大和病理心肌肥大模型心室肌球蛋白α和β重链的变化进行比较研究,结果发现大鼠经10周游泳训练后引起心肌肥大,心室肌球蛋白α重链百分比和肌原纤维ATPase活性升高,β重链百分比降低(p<0.05)。与此变化相反,自发性高血压大鼠和由异丙肾上腺素诱导的心肌肥大大鼠心室肌球蛋α重链百分比和肌纤维ATPase活性降低,β重链百分比升高(P<0.05)。说明运动心脏的重塑过程不同于病理性心脏,前者重塑后使心肌收缩性提高,后者重塑后心脏功能降低。

To understand the characteristics of physiological cardiac hypertrophy remodeling,myosin isoen-zymic changes were studied in several experimental models:swimming-induced physological cardiac hypertrophy (SWI) , isoproterenol-induced pathological cardiac hypertrophy (ISO), spontaneously hypertensive rats(SHR) .controls of SD rats (CN) and Wistar Kyoto (WKY), The isoenzymic composition of cardiac myosin was analyzed by SDS-PAGE electrophoresis. The results showed that the a-MHC (myosin heave chain)and myofibril ATPase activity increased by 9% and 72% respectively,B-MHC decreased by 23% in SWI,compared with CN(p<0.05). The a-MHC and myofibril ATPase activity decreased by 30% and 20% respectively, B-MHC increased by 76% in ISO,compared with CN (p<0. 05). The a-MHC and myofibril ATPase activity also decreased by 30%and 41 % respectively ,B-MHC increased by 46%in SHR,compared with WHK (p<0. 05). It suggested that were different remodeling characteristics between physiological and pathological cardiac hypertrophy.