Adverse effects of arsenic exposure on uterine function and structure in female rat

The present investigation examined the adverse effects of arsenic exposure on uterine function and structure of female rat at 56 days of age, exposed to different doses (50, 100, and 200 ppm) of sodium arsenite in drinking water at immature age (28 days) for 28 days. Dose-dependent decrease (P<0.001) was observed in mean uterine weight and length in all treated groups compared to control. Higher arsenic deposition was found in uterine tissue against increased doses of arsenite. Arsenite treatment altered the histomormphology of the uterus. Uterine epithelium in 50 ppm group was lined by cuboidal cells instead of columnar cells observed in control epithelium. In 100 and 200 ppm groups, no demarcation was observed between epithelial cells and endometrial stroma. No basement membrane was seen in these groups; even in 50 ppm, basement membrane was disturbed. The endometrial stroma in 100 and 200 ppm groups was very dense in appearance and contained irregular-shaped cells. In myometrium, loosening of cells was observed in 100 and 200 ppm groups. Dose-dependent decrease (P<0.001) was observed in mean uterine diameter, epithelial height, thickness of endometrium, myometrium, and in plasma levels of estradiol, progesterone, FSH and LH in all the treatment groups compared to control. In summary, arsenic is a major threat to female reproductive health acting as a reproductive toxicant and as an endocrine disruptor, restricted the function and structure of uterus, by altering the gonadotrophins and steroid levels, not only at high dose concentration but also at low (50 ppm) levels, when they become mature.