Histomorphometric analysis of cardiomyocytes and collagen deposition in the heart muscle of ovariectomized rats

Abstract

This study aimed to evaluate the effect of oophorectomy on the morphometric variables of cardiomyocytes and quantification collagen in Wistar rats. Twenty rats were used and divided into two groups: GI - ovariectomized and GII - sham-ovariectomized. After recovery from anesthesia the animals were housed in separate cages and under the conditions of light / dark cycle 12/12h for a period of six months. After the experimental period, the animals were anesthetized, the heart removed and immersed in 10% formaldehyde. The fragments of the ventricles were subjected to histological analysis and stained with hematoxylin and eosin. Histomorphometric analysis (cell area and nuclear area and volume) were performed by light microscopy and ImageJ software version 1.44. The data were submitted to ANOVA and when significant, complemented by Student's t test (p < 0.001). There was a significant decrease in cellular and nuclear areas of the GI cardiomyocytes compared to GII and the area occupied by collagen was greater in cardiac muscle GI, when compared to GII. Therefore, it is concluded that the changes observed in the GI group cardiomyocytes, suggest a higher apoptotic activity in this group, due to decreased serum estrogen levels caused by ovariectomy and increased area occupied by collagen in oophorectomized group is associated the cardioprotective effect of estrogen.