Effects of resistance exercise on ascendent aorta on ovariectomized elderly rats

ABSTRACT

Studies have shown a strong relationship between menopause, diet, physical inactivity and presence of risk factors causing endothelial and tissue damages, leading to increased risk of developing cardiovascular disease. The aim of this study was to investigate the influence of resistance training on the effects of estrogen deprivation in aortic collagen and elastic tissue in aging. Fifteen Wistar female rats, 4 months-old, average weight 240 g were studied. All animals were ovariectomized at 6 months of age, after divided into 3 groups (n = 5) Sedentary adult (13 months), Sedentary old and Trained old (both with 17 months). All animals were ovariectomized at 6 months of age. The animals were observed for 8 months after its ovariectomy and then submitted to resistance training protocol during 12 weeks. At the end of the experiment the animals were euthanized. Samples of the ascending aorta were sectioned, fixed, processed and stained for examination by light microscopy. Photomicrographs were used for stereological study and analyzed the following parameters body weight, volume density of collagen fibers and elastic lamellae. No significant difference was found between the initial and final weights in the studied groups. Resistance training attenuates the increase in volume density of elastic lamellae (21%) and collagen fibers (16%), when compared with the sedentary older group.