title: Selective expression of a progesterone receptor on the human sperm surface.
abstract: OBJECTIVE
  To visualize progesterone (P) binding sites on the sperm surface, examine the relationship between hormone binding and hormone action (acrosome reaction), and determine the size of the hormone-responsive sperm subpopulation.
  
  
  METHODS
  Kinetic analysis of P binding was combined with the assessment of the hormone effect using a fluorescent acrosomal marker.
  
  
  METHODS
  Private hospital, medical research center, and a university-based andrological laboratory.
  
  
  METHODS
  Sperm samples were from healthy volunteers with normal spermiogram values.
  
  
  METHODS
  None.
  
  
  METHODS
  Progesterone binding was analyzed by fluorescence microscopy and flow cytometry using P coupled to fluorescein isothiocyanate-labeled bovine serum albumin. Tetramethylrhodamine isothiocyanate-labeled Pisum sativum agglutinin was used as acrosomal marker in double-labeling experiments.
  
  
  RESULTS
  After in vitro capacitation, only few spermatozoa (approximately 10%) were able to bind P to the cell surface, but most of these cells subsequently generated the acrosome reaction in response to hormone binding.
  
  
  CONCLUSIONS
  The expression of P receptor sites on the human sperm surface is a major factor controlling the P-induced acrosome reaction. Further studies are warranted to explore if defective expression of the receptor can compromise fertility.
authors.affiliation: Center for Reproductive Biology and medicine, American Hospital of Paris, Neuilly-sur-Seine, France.
authors.forename: J
authors.initials: J
authors.lastname: Tesarik
authors.forename: C
authors.initials: C
authors.lastname: Mendoza
authors.forename: J
authors.initials: J
authors.lastname: Moos
authors.forename: A
authors.initials: A
authors.lastname: Carreras
mesh_terms: D001665:Binding Sites; D006690:Bisbenzimidazole; D016650:Fluorescein-5-isothiocyanate; D005456:Fluorescent Dyes; D006801:Humans; D037102:Lectins; D008297:Male; D037121:Plant Lectins; D011374:Progesterone / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D012235:Rhodamines; D012710:Serum Albumin, Bovine; D013094:Spermatozoa / Q000378:metabolism* / Q000648:ultrastructure
chemical_list: D005456:Fluorescent Dyes; D037102:Lectins; D037121:Plant Lectins; D011980:Receptors, Progesterone; D012235:Rhodamines; C036292:pea lectin; D012710:Serum Albumin, Bovine; C009434:tetramethylrhodamine isothiocyanate; D011374:Progesterone; D016650:Fluorescein-5-isothiocyanate; D006690:Bisbenzimidazole