These authors contributed equally for this study.
The Functional Role of Oxytocin in the Induction of Oocyte Meiotic Resumption in Cattle
Article first published online: 21 MAY 2013
© 2013 Blackwell Verlag GmbH
Reproduction in Domestic Animals
Volume 48, Issue 5, pages 844–849, October 2013
How to Cite
De Cesaro, M., Trois, R., Gutierrez, K., Siqueira, L., Rigo, M., Glanzner, W., Oliveira, J. and Gonçalves, P. (2013), The Functional Role of Oxytocin in the Induction of Oocyte Meiotic Resumption in Cattle. Reproduction in Domestic Animals, 48: 844–849. doi: 10.1111/rda.12173
- Issue published online: 13 SEP 2013
- Article first published online: 21 MAY 2013
- Manuscript Accepted: 10 MAR 2013
- Manuscript Received: 13 AUG 2012
The aim of the present study was to examine the role of oxytocin (OT) in the progesterone (P4) and prostaglandins (PGs) pathway to induce oocyte meiotic resumption. Cumulus–oocyte complexes were co-cultured with follicular hemisections for 15 h to determine the effects of different doses of OT or atosiban (ATO; oxytocin receptor antagonist) on oocyte meiotic resumption. In another experiment, we examined the effect of the interaction between P4, OT and PGs on the regulatory cascade of the oocyte meiotic resumption. Oxytocin at 1 μm was effective in inducing meiotic resumption in oocytes co-cultured with follicular cells (84.0%), not differing from the positive control group (74.4%). Atosiban inhibited in a dose-dependent manner the positive effect of OT on the meiotic resumption (27.6% metaphase I with 10 μm of ATO, which did not differ from the 25.5% of the negative control group). Furthermore, a third experiment showed that P4 was able to induce oocyte meiotic resumption, which was inhibited by ATO. However, the OT positive effect was not blocked by mifepristone (P4 antagonist), but was inhibited by indomethacin (a non-selective PTGS2 inhibitor). Collectively, these data suggest a sequential role of P4, OT and PGs in the induction of oocyte meiotic resumption.