Membrane adenylate cyclase regulation in bovine sperm capacitation and oxidative metabolism and in putative zygote redox state

SILVINA FERNÁNDEZ; SERGIO MORADO; PABLO CETICA; MARIANA CÓRDOBA

Buenos Aires

Jornada; V Jornadas INITRA; 2017

Mammalian sperm requires going through a series of events in the female reproductive tract, known as sperm capacitation, to be capable of fertilizing the oocyte. Although heparin is the most commonly used capacitation inducer in vitro, hyaluronic acid has been recently used for capacitation induction as well as for other reproductive biotechnologies such as sperm selection and in vitro fertilization (IVF). Membrane associated-adenylate cyclase (mAC) participates in intracellular signaling for sperm in vitro capacitation triggered by heparin and hyaluronic acid. The aim of this work was to study the effect of mAC inhibition on sperm capacitation and cleavage rate and redox state in putative bovine zygotes. Hyaluronic acid was used as capacitation inducer and 2`,5`- dideoxyadenosine (2,5-D) as an specific mAC inhibitor. Capacitation was evaluated by chlorotetracicline epifluorescence technique, sperm viability by trypan blue stain and oxygen consumption determined by polarography. For IVF frozen sperm was thawed in modified synthetic oviduct fluid (mSOF), then centrifuged and resuspended to a final concentration of 2x10 6 motile sperm cells/ml. Cumulus-oocyte complexes and sperm samples were co-incubated in mSOF with the addition of bovine serum albumin and heparin or hyaluronic acid at 39°C and 5% CO2 in humidified air during 21 hours. Redox state was determined by RedoxSensor Red CC-1. Data were analyzed by ANOVA and Tukey tests (P