MATERIALS AND METHODS: Intact pregnant rats were administered 1 mg/kg/day testosterone alone or in combination with flutamide, finasteride or anastrozole, subcutaneously on day-1 of pregnancy till day 3. The rats were sacrificed at day 4 of pregnancy, which was considered as the uterine receptivity period for determining the expression and distribution of connexin 26 and connexion 43 by immunohistochemistry and quantitative polymerase chain reaction, respectively.
RESULTS: Treatment with 1 mg/kg/day testosterone increased connexin 26 and decreased connexin 43 mRNA expression and protein distribution in the uterus of early pregnancy rats.
CONCLUSION: Changes in the uterine connexin 26 and connexin 43 expression by testosterone could disrupt embryo implantation, resulting in early pregnancy loss.