ASSOCIAÇÃO DO HORMÔNIO DO CRESCIMENTO COM EXERCÍCIO RESISTIDO SOBRE A MORFOLOGIA, EXPRESSÃO GÊNICA E MARCADOR CARDÍACO

Abstract

Objective-This study aimed to evaluate the effects of growth hormone (GH), in rats submitted to resistance training (RT) on cardiac remodeling in morphological aspects, Ca2+ genes and cardiac marker. Design- Wistar male rats were divided into 4 groups: control (CT, n = 7), Growth Hormone (GH, n = 7), Resistance Training (RT, n = 7) and Resistance Training with Growth Hormone administration (RTGH, n = 7). The GH dose was 0,2 IU/kg through subcutaneous administration every two days, and the RT model used was the vertical jump in water (4 sets of 10 jumps/day, 3 sessions/week) both for 30 consecutive days. Anatomical variables such as final body weight (FBW), left ventricle weight (LV) and the LV/FBW ratio of rats were evaluated. The morphology analysis consisted of the cardiomyocytes cross-sectional area (HE) and collagen fraction (picrosirius). The mRNA of the proteins of the calcium pump of the sarcoplasmic reticulum Ca2+ ATPase (SERCA2a), phospholamban (PLB) and ryanodine (RyR) infarction were evaluated by real-time PCR (qPCR). The cardiac marker dosed was creatine kinase muscle-brain fraction (CK-MB), through serum analysis Results- FBW, LV weight, LV/FBW ratio, cardiomyocytes cross-sectional area, as and SERCA2a, PLB and RyR gene expression, showed no statistical difference between the groups, whereas for the collagen assessment , an increase in RT group (p <0,05) was observed when compared to other groups (CT, GH and RTGH). In biochemical analysis of CK-MB there was statistical difference between trained groups and untrained groups. Conclusion- The RT interferes with cardiac remodeling by increasing interstitial collagen, which may result from the myocardial injury characterized by increased CK-MB, however, when combined with GH collagen remained unchanged.