Role of multidrug resistance protein 4 (MRP4) and the mechanisms involved in the regulation of its activity during mouse sperm capacitation

BUFFONE MG; ALONSO CAI; PEREZ-MARTINEZ S; LUQUE GM; DAVIO C; LOTTERO-LECONTE R

Ciudad Autonoma de Buenos Aires

Congreso; Reunión Conjunta de Sociedades de Biociencias.; 2017

In mammals, sperm capacitation correlates with HCO3- influx, activationof soluble adenylyl cyclase (sAC), cAMP increase, PKA activation(pPKA), and increase in tyrosine phosphorylation (pY). cAMPlevels are mainly regulated by its synthesis and degradation, but itsextrusion through multidrug resistance protein 4 (MRP4) transporteris also involved in this modulation. Previously, we found that cAMPefflux by MRP4 is critical for pY occurrence in mouse SPZ. Moreover,our results indicated that ∼50% of SPZ that undergo capacitation,lose MRP4. Here, we aim to deepen into the role of MRP4 duringsperm capacitation. To support the involvement of MRP4 in capacitation,we performed in vitro fertilization (IVF) assays, incubatingSPZ in capacitating conditions (CC) in the presence or not of MK571(MK), a specific MRP4 inhibitor. Results showed a decrease in the% of IVF when SPZ were incubated with MK (p