IGEVET-Institute of Veterinary Genetic “Prof. Fernando N. Dulout” (UNLP-CONICET LA PLATA), Faculty of Veterinary
Sciences, National University of La Plata, La Plata, Buenos Aires, Argentina
Bee Reasearch Center, Department of Biology, FCEy N, National University of Mar del Plata - CONICET, Mar del Plata,
Buenos Aires, Argentina
IGEVET-Institute of Veterinary Genetic “Prof.
Fernando N. Dulout” (UNLP-CONICET LA PLATA)
Faculty of Veterinary Sciences
National University of La Plata
Any use, distribution, reproduction or abstract of this publication in any medium, with the exception of commercial purposes, is permitted provided the original work is properly cited. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Expression of Ghrelin and Its Receptor mRNA in Bovine
Oocyte and Cumulus Cells .
Int J Fertil Steril.
Energy balance is regulated by ghrelin which is a neuroendocrine modulator. Ghrelin is expressed in repro-
ductive organs. However, the role of ghrelin during in vitro maturation (IVM) and bovine preimplantational
development is limited. The purpose of this study was to measure the expression of ghrelin (GHRL) and
its receptor growth hormone secretagogue receptor 1A (GHS-R1A) mRNA, and determine cumulus oocyte
complex (COC) viability after IVM with 0, 20, 40 and 60 pM of ghrelin. Also, pronuclear formation was
recorded after in vitro fertilization (IVF). GHRL and GHS-R1A mRNA expression in oocyte and cumu-
lus cells (CCs) was assessed using reverse transcription-polymerase chain reaction (PCR). Oocyte and
CC viability were analyzed with the fluorescein diacetate fluorochrome-trypan blue technique. Pronuclear
formation was determined 18 hours after IVF with Hoechst 33342. The results demonstrated that ghrelin
mRNA is present in oocyte and CCs before and after 24 hours IVM with all treatments. Ghrelin receptor,
GHS-R1A, was only detected in oocytes and CCs after 24 hours IVM with 20, 40 and 60 pM of ghrelin.
Oocyte viability was not significantly different (P=0.77) among treatments. However, CC viability was
significantly lower (P=0.04) when COCs were matured with ghrelin (77.65, 72.10, 66.32 and 46.86% for
0, 20, 40, and 60 pM of ghrelin, respectively). The chance of two pronuclei forming were higher (P=0.03)
when ghrelin was not be added to the IVM medium. We found that ghrelin negatively impacts CC viability
and pronuclear formation.