Swimming training promotes cardiac remodeling and alters the expression of mRNA and protein levels involved in calcium handling in hypertensive rats.

Abstract

Aim: The aim of this study was to identify the effects of swimming training on the mRNA expression and protein levels of the calcium handling proteins in the hearts of renovascular hypertensive rats submitted to swimming protocol during 6 weeks. Main methods: Fischer ratswith renovascular hypertension 2-kidney 1-clip (2K1C) and SHAMgroups were divided among sedentary and exercised groups. The exercise protocol lasted for 6 weeks (1 h/day, 5×/week), and the mean arterial pressure, cardiomyocytes hypertrophy parameters, mRNA expression and protein levels of some calcium handling proteins in the left ventricle were evaluated. Key findings: Swimming training was able to reduce the levels of mean arterial pressure in the hypertensive group compared to 2K1C SED, and to promote cardiac hypertrophy in SHAM EX and 2K1C EX groups in comparison to the respective control groups. The mRNA levels of B-type natriuretic peptide were reduced in the 2K1C EX when compared to 2K1C SED. The mRNA and protein levels of the sarcoplasmic reticulumCa2+-ATPase increased after the swimming training in SHAMand 2K1C groups. ThemRNA and protein levels of phospholamban, displayed an increase in their levels in the exercised SHAMand in hypertensive rats in comparison to their respective controls; while mRNA levels of Na+/Ca2+ exchanger was reduced in the left ventricle comparing to the sedentary hypertensive rats. Significance: Taken altogether,we provide evidence that the aerobic training may lead to cardiac remodeling, and modulate the calcium handling proteins expression in the heart of hypertensive rats.