Influence of the cumulus and gonadotropins on the metabolic profile of porcine cumulus-oocyte complexes during in vitro maturation

The aim of this work was to examine the influence of the cumulus and gonadotropins on the metabolic profile of porcine cumulus oocyte complexes (COCs) during in vitro maturation. Immature COCs were assigned to morphological classes A1 (with a dense cumulus), A2 (with a translucent cumulus), B1 (with the corona radiata), B2 (with only some remaining cumulus cells) and matured with or without gonadotropins. Glycolysis and ammonia production were higher in the A class COCs; gonadotropins increased both, especially in the A1 COCs (p<0.05). The A class COCs had the highest initial protein contents and at the end of in vitro maturation. Furthermore, hormonal stimulation induced a similar increase in protein contents of both A classes (p