Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
J Clin Endocrinol Metab. 2005 Feb;90(2):984-91. Epub 2004 Nov 23.

Human sperm express cannabinoid receptor Cb1, the activation of which inhibits motility, acrosome reaction, and mitochondrial function.

Author information

  • 1Department of Medical and Surgical Sciences, Clinica Medica 3, University of Padova, Via Ospedale 105, 35128 Padova, Italy. marco.rossato@unipd.it

Abstract

Cannabinoids and endocannabinoids negatively influence sperm functions. These substances have been demonstrated in many mammalian tissues, including male and female reproductive tracts, and previous studies have shown the presence of functional receptors for cannabinoids in human sperm. The present study, by means of RT-PCR and Western blot techniques, demonstrates that human sperm express the CB(1), but not CB(2), cannabinoid receptor (CB-R) subtype located in the head and middle piece of the sperm. The activation of this receptor by anandamide reduces sperm motility and inhibits capacitation-induced acrosome reaction. Activation of the CB(1)-R did not induce any variation in sperm intracellular calcium concentrations, but produced a rapid plasma membrane hyperpolarization that was reduced by the K(+) channel blocker tetraethylammonium. The effects of anandamide on human sperm motility were dependent on the reduction of sperm mitochondrial activity as determined by rhodamine 123 fluorescence. The specificity of anandamide effects in human sperm were confirmed by the effects of the CB(1)-R antagonist SR141716. These findings provide additional evidence that human sperm express functional CB(1)-R, the activation of which negatively influences important sperm functions, and suggest a possible role for the cannabinoid system in the pathogenesis of some forms of male infertility.

PMID:
15562018
[PubMed - indexed for MEDLINE]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Icon for Atypon
    Loading ...
    Write to the Help Desk