The Sodium-Proton Exchangers sNHE and NHE1 Control Mouse Sperm Plasma Membrane Hyperpolarization During Capacitation

NOVERO, ANALIA G.; TORRES RODRÍGUEZ, PAULINA; DE LA VEGA BELTRÁN, JOSÉ L.; SCHIAVI-EHRENHAUS, LIZA J.; LUQUE, GUILLERMINA M.; STIVAL, CINTIA; GENTILE, IÑAKI; RITAGLIATI, CARLA; SANTI, CELIA M.; NISHIGAKI, TAKUYA; KRAPF, DIEGO; BUFFONE, MARIANO G.; DARSZON, ALBERTO; TREVIÑO, CLAUDIA L.; KRAPF, DARIO

Congreso; American Society of Andrology 49th Annual Conference; 2024

Introduction and objectivesSuccessful fertilization in mammals requires a process known as sperm capacitation that can be mimicked in vitro n a defined culture medium. Hyperpolarization of the sperm plasma membrane potential (Em) is a key event associated with capacitation, and correlates with success in human assisted reproductive techniques. It is triggered by the opening of the SLO3 potassium channels. The regulation of Em is poorly understood, but previous evidence has implicated the role of cAMP/PKA in this process.The objective of this study was to unveil the molecular mechanisms that trigger hyperpolarization during capacitation.MethodsSperm from WT, sNHE KO, Slo3 KO and CatSper KO cauda epididymis mouse genetic models were incubated under capacitating conditions with the aid of different pharmacological inhibitors. DISC3(5) and BCECF were used to determine Em and pH respectively, by microscopy, flow cytometry, and fluorimetry.ResultsPKA inhibition by sPKI, did not block Em hyperpolarization (n>5, p