Effects of exercises on the right ventricle of female micesubmitted to ovarian hormone deprivation

ABSTRACT

Introduction: Several studies indicate that the estrogen deficiency increase the incidence of the cardiovascular diseases in women in post-menopausal period and that the exercise program may prevent or relieve problems such as cardiovascular disease, obesity, muscle weakness, osteoporosis and depression. The effects of the estrogen deprivation in the myocardium still remain unclear, mainly in the right ventricle. The aim was to investigate the effects of exercises on the right myocardium in the female mice subjected to deprivation of ovarian hormones. Material and methods: A total of 15 female mice at 9 months of age, divided into 3 groups (n = 5) were studied non-ovariectomized sedentary (S); ovariectomized sedentary (OS), ovariectomized trained (OT) animals. Ovariectomy was performed at 9 months of age and physical training began 7 days after surgery. The animals underwent a physical training protocol for 4 weeks on a treadmill with progressive speed and load (one hour a day/5 days a week at 50 to 65% of the maximum speed of running). After the experimental proceeding, the heart were removed and processed accordingly to conventional protocol for optical microscopy, and the slides stained by the methods of Hematoxylin and Eosin Stereology was used to analyze the components of the myocardium. Results: Ours results indicate that the exercise training promoted cardiomyocyte hypertrophy, increase in connective tissue with decreased cardiomyocytes. Conclusion: Our data suggest that moderate exercise promoted right ventricular remodeling with cardiomyocyte hypertrophy and increase in connective tissue, to fit the modifications promoted by exercise in the left ventricle.