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Updated: Jul 13, 2026
09:37
Recording Electrical Currents across the Plasma Membrane of Mammalian Sperm Cells
Published on: February 14, 2021
Ion channels in sperm motility and capacitation
A Darszon1, C L Treviño, C Wood
1Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México (UNAM), Cuernavaca, Morelos, México. darszon@ibt.unam.mx
Society of Reproduction and Fertility Supplement
|July 25, 2007
Summary
Spermatozoa use ion channels for essential functions like motility and fertilization. Membrane potential changes, particularly hyperpolarization, are crucial for activating calcium channels in both sea urchin and mouse sperm.
Area of Science:
- Reproductive Biology
- Cell Physiology
- Ion Transport
Background:
- Spermatozoa rely on ion channels for critical processes including motility and fertilization.
- Ion channels regulate intracellular calcium ([Ca2+]i), membrane potential (Em), and pH (pHi), influencing sperm function.
- Speract peptide in sea urchin sperm and capacitation in mammalian sperm involve significant ion flux and Em changes.
Purpose of the Study:
- To investigate the role of ion channels and membrane potential in sperm function, specifically motility and fertilization.
- To elucidate the mechanisms of ion channel involvement in sea urchin sperm response to speract and mammalian sperm capacitation.
- To identify specific ion channels, such as voltage-dependent calcium channels (Ca(v)s), KATP channels, and ENaCs, in these processes.
Main Methods:
- Electrophysiological recordings to measure membrane potential (Em) and ion fluxes.
- Immunological techniques to detect ion channel presence.
- Molecular-biological experiments to identify ion channel genes and expression.
- Pharmacological manipulations to assess the effects of channel modulators on sperm function.
Main Results:
- Speract induces Ca2+ influx via voltage-dependent calcium channels (Ca(v)s) in sea urchin sperm, modulated by Em changes.
- Mammalian sperm capacitation involves increased [Ca2+]i and pHi, and Em hyperpolarization.
- In mouse sperm, inwardly rectifying K+ channels (KATP channels) and epithelial Na+ channels (ENaCs) are present, with KATP channel opening and ENaC closure contributing to hyperpolarization.
- Em hyperpolarization appears essential for removing inactivation from Ca(v) channels in both sea urchin and mouse sperm.
Conclusions:
- Ion channels and regulated membrane potential changes are fundamental to sperm motility and fertilization.
- Specific ion channels, including Ca(v)s, KATP channels, and ENaCs, play distinct roles in sperm activation and capacitation.
- Membrane potential hyperpolarization is a conserved mechanism enabling Ca(v) channel function necessary for sperm fertilization.
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