RESUMO
Background: Physical exercise is known to be a stressor stimulus that leads to reproductive disruption
Objective: The aim of this study was to evaluate the effect of forced swimming on the uterus and ovaries in mice
Materials and Methods: Adult mice [N=24] were divided into the following three groups: A, control; B, swimming in water [10°C]; and C, swimming in water [23°C]
Swimmers swam for 5 min daily for 5 consecutive days/ wk during 2 wks. An enzyme linked immunosorbent assay was used to determine serum estradiol, follicle stimulating hormone [FSH] and testosterone levels. Immunohistochemistry was performed to study apoptotic cells or estrogen receptor [ER] expression in uterine epithelial cells and ovaries. ANOVA was used for statistical analysis
Results: Swimming in both groups reduced the serum FSH and estradiol levels [p<0.01] without having a significant effect on the serum testosterone level or percentage of apoptosis in ovarian and uterine tissues [p<0.01] compared with controls. A significant reduction in the number of ERs in the uterus and ovaries, and secondary and graafian follicles were observed in groups B and C compared with controls [p<0.01]; however the number of primordial and primary follicles were not significantly changed in the ovaries
Conclusion: Forced swimming of 2 wks duration reduces the serum levels of FSH and estradiol without having effects on apoptosis in the ovaries or uteri of mice
Over a long period of time, forced swimming may have an adverse effect on fertility