Oxytocin receptor expression in developing mouse gonads and its modulation by high-dose folic acid

The oxytocin receptor (OTR) is known to be expressed in various organs, including the adult reproductive system. However, its expression in developing gonads has not yet been reported. This study investigates OTR expression in the ovaries and testes during critical developmental stages, specifically embryonic day 13.5 (E13.5), embryonic day 18.5 (E18.5), and postnatal day 14 (P14). According to our findings, both developing ovaries and testes exhibited OTR expression, including in immature follicle and Sertoli cells. OTR-expressing cells increased in the developing ovary, while a decrease was observed in the postnatal testis. In addition, our results showed that a high dose folic acid (FA) diet affected the number of OTR-expressing cells in developing gonads, particularly during the later stages of embryogenesis. These findings suggest that OTR may play a role in gonadal development and that its expression is influenced by sex. Furthermore, changes in folic acid supplementation may interfere with this developmental process.