RESUMO
Arsenic is a toxic mutagenic metalloid and a major pollutant of water. Exposure to arsenic produces various adverse reproductive effects. Human chorionic gonadotropin [hCG] has an important role in the female reproductive system. The aim of the study was to investigate the effects of sodium arsenite on the structure of the endometrium of adult rats and evaluate the possible role of hCG in the amelioration of these changes. Thirty-six adult female rats were used in this study. They were divided into three equal groups: group I [the control group]; group II, in which the animals received sodium arsenite orally for 28 days; and group III, in which the animals were subcutaneously injected with hCG for 28 days, together with the previous dose of sodium arsenite. Specimens of the endometrium were taken at diestrous phase and prepared for light and scanning electron microscopic examinations. Moreover, morphometric measurements were taken to measure the height of the surface epithelium and the diameter and number of endometrial glands, and the results were statistically analyzed. Arsenite treatment prolonged the diestrous phase. The surface epithelium showed a significant reduction in height as compared with the control group and some parts showed focal degeneration and shedding. The endometrial stroma showed irregularly shaped cells and an apparent increase in collagen fibers. Small and atrophied glands were seen. Scanning electron microscopic examination revealed a decrease in the number of cells with pinopodes and a decrease in the number of pits of glands. Concomitant administration of arsenite and hCG resulted in regular estrous cycles. The structure of the endometrium was improved as compared with that of the arsenic-treated group. Sodium arsenite altered the structure of the endometrium and the phases of the estrous cycle. Concomitant administration of hCG with arsenic improved the structure of the endometrium and the regularity of the estrous cycle