Anomalies in ovary following oral exposure to oxytocin: Mechanistic studies

•25 days oral OT exposure to 10 days old pups resulted in increased ovulation.•OT showed increase in ovarian weight and total number of follicles and CLs.•OT induced ovulation may involved up regulation of pEGFR and pERK1/2.•OT also up regulate the HAS-2 & TSG-6, COX-2 and GDF-9 proteins.

Ovarian anomalies following oral oxytocin (OT) (1 and 10 ng/100 μl) exposure of female Wistar rat pups (10-day old) for 25 days was undertaken as OT injections are illegally used for milk let down in cattle thereby causing oral exposure to human population from early age. OT exposure resulted in increased ovarian weight, γ globulin, total number of follicles, and number of corpus luteum (CLs); indicating higher ovulation. The mechanism may involve over-expression of pEGFR followed by downstream pERK1/2 and subsequently increased ovarian PGE-2 along with enhanced COX-2, HAS-2 & TSG-6 (matrix deposition proteins) and GDF-9 (oocyte factor) proteins, suggesting that oral exposure of OT may affect the physiology and function of the ovary. Further, in vitro studies showed increased internalization of OT in IEC-6 cells which further supports that orally administered OT may cause altered manifestations as shown above following internalization in mucosal membrane.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide