Exercise training decreases myocardial collagen III and heart failure signs rate, and improves physical performance in spontaneously hypertensive rats (LB522)

Abstract

The aim of this study was to evaluate the influence of physical exercise on physical performance, heart failure (HF) signs rate, and myocardial collagen I and III and lysyl oxidase protein expression in spontaneously hypertensive rats (SHR). Methods: Sixteen‐month‐old SHR were divided into two groups: sedentary (SED, n=8) and exercise (EXE, n=8). Physical training was performed 5 times per week for 16 weeks in a treadmill. Physical performance was assessed by exercise test on a treadmill with a gradual speed increase. At the moment of euthanasia, HF signs were evaluated: tachypnea in vivo, and ascyte, pleural effusion, atrial thrombi, right ventricular hypertrophy, and liver and lung congestion post mortem. Collagen I and III and lysyl oxidase protein expression were analyzed by Western blot. Statistics: The Student's t test and the Goodman test were used to compare the groups (p<0.05). Results: The EXE group showed greater physical capacity and lower HF signs rate than SED group. Collagen III protein expression was lower in EXE group (1.00±0.58 vs. 0.73±0.43, p<0.05). Collagen I and lysyl oxidase protein expression were not significantly different between groups. Conclusion: Physical exercise improves physical performance and reduces heart failure signs rate and myocardial collagen III expression in spontaneously hypertensive rats.Grant Funding Source: Supported by CAPES and CNPq