Influencia del cumulus y las gonadotrofinas en el perfil metabólico de los complejos ovocito-cumulus porcinos durante la maduración in vitro

GABRIEL MARTIN ALVAREZ

Potrero de los Funes, San Luis

Jornada; XXX Reunión Anual de la Sociedad de Biología de Cuyo; 2012

Sociedad de Biología de Cuyo

The substrate availability during in vitro culture of cumulus oocyte complexes (COCs) strongly impacts on oocyte maturation. Several aspects of porcine COC metabolism during in vitro maturation remain to be elucidated. The aim of the work was to examine the influence of the cumulus and gonadotropins on the metabolic profile of porcine 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 < 0.05). The neutral lipid content and ROS levels were similar in the immature oocytes of the COCs of all classes. A reduction was seen in both these variables when maturation proceeded either in the presence or absence of gonadotropins. The cumulus type surrounding the oocyte is related to the metabolism of carbohydrates and amino acids by the COC during in vitro maturation under gonadotropic stimulation. Oocyte lipolytic activity and ROS production appear to be independent of the surrounding cumulus and the presence of gonadotropins.