INTRACELLULAR REDISTRIBUTION OF CARDIAC ENDOTHELIN-1 RECEPTOR IN RAT DURING MYOCARDIAL HYPERTROPHY
- Author:
Xiaohong WANG
1
;
Yongfen QI
;
Jun YANG
;
Lijia TONG
;
Yongzheng PANG
;
Chaoshu TANG
Author Information
1. Institute of Cardiovascular Research, the First Hospital of Peking University,
- From:
Chinese Medical Sciences Journal
2001;16(2):86-92
- CountryChina
- Language:Chinese
-
Abstract:
Objective. In a model of rat cardiac hypertrophy, the changes in the distribution of ET-1 receptors in two subcellular fractions, the sarcolemma and the light vesicles during myocardial hypertrophy were studied. Methods. Cardiac hypertrophy was produced by placing a constricting clip around the suprarenal abdominal aorta of rats, and ET-1 receptor was assayed with radioactive analysis method. Results. It was found that plasma and ventricular ET-1 levels increased significantly on week 2 and week 4 of pressure overload. ET-1 binding studies showed that during myocardial hypertrophy, the maximum binding capacity (Bmax) was increased by 41％ (P<0.01) and 65％ (P< 0.01) in sarcolemma in H-2 week and H-4 week groups, but was decreased by 24％ (P< 0.01) and 21％ (P< 0.01) in light vesicles. The sum of Bmax of sarcolemmal and light vesicle fractions was increased by 33％ (P< 0.01) and 57％ (P< 0.01) in group H-2 week and H-4 week, respectively. ? Conclusion. ET-1 receptors in rat heart were externalized from light vesicles to sarcolemma, which may contribute to the development of myocardial hypertrophy.
