title: Papaverine-sensitive phosphodiesterase activity is measured in bovine spermatozoa.
abstract: Cyclic adenosine monophosphate (cAMP) plays a crucial role as a signaling molecule for capacitation, motility, and acrosome reaction in mammalian spermatozoa. It is well-known that cAMP degradation by phosphodiesterase (PDE) enzyme has a major impact on sperm functions. This study was undertaken to characterize cAMP-PDE activity in bovine spermatozoa. Total cAMP-PDE activity in cauda epididymal and ejaculated spermatozoa was 543.2 ± 49.5 and 1252.6 ± 86.5 fmoles/min/106spermatozoa, respectively. Using different family-specific PDE inhibitors, we showed that in cauda epididymal and ejaculated spermatozoa, the major cAMP-PDE activity was papaverine-sensitive (44.5% and 57.5%, respectively, at 400 nm, papaverine is a specific inhibitor of the PDE10 family). These data are supporting the functional presence of PDE10 in bovine spermatozoa and were further confirmed by western blot to be PDE10A. Using immunocytochemistry, we showed immunoreactive signal for PDE10A present on the post-acrosomal region of the head and on the flagella of ejaculated spermatozoa. Using papaverine, we showed that it promotes tyrosine phosphorylation of sperm proteins, phosphorylation of Erk1 and Erk2, and Ca2+release from Ca2+store. These results suggest that PDE10 is functionally present in bovine spermatozoa and is affecting different molecular events involved in capacitation, most probably by cAMP local regulation.
authors.affiliation: Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Université Laval, Québec, QC, Canada.|Département des Sciences Animales, Faculté des Sciences de L'agriculture et de L'alimentation, Université Laval, Québec, QC, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Bergeron
authors.affiliation: Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Université Laval, Québec, QC, Canada.|Département des Sciences Animales, Faculté des Sciences de L'agriculture et de L'alimentation, Université Laval, Québec, QC, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Hébert
authors.affiliation: Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Université Laval, Québec, QC, Canada.|Département des Sciences Animales, Faculté des Sciences de L'agriculture et de L'alimentation, Université Laval, Québec, QC, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Guillemette
authors.affiliation: Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Université Laval, Québec, QC, Canada.|Département des Sciences Animales, Faculté des Sciences de L'agriculture et de L'alimentation, Université Laval, Québec, QC, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Laroche
authors.affiliation: Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Université Laval, Québec, QC, Canada.|Département des Sciences Animales, Faculté des Sciences de L'agriculture et de L'alimentation, Université Laval, Québec, QC, Canada.
authors.forename: M-P
authors.initials: MP
authors.lastname: Poulin
authors.affiliation: Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Université Laval, Québec, QC, Canada.|Département des Sciences Animales, Faculté des Sciences de L'agriculture et de L'alimentation, Université Laval, Québec, QC, Canada.
authors.forename: J P
authors.initials: JP
authors.lastname: Aragon
authors.affiliation: Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Université Laval, Québec, QC, Canada.|Département Obstétrique, Gynécologie et Reproduction, Faculté de Médecine, Université Laval, Québec, QC, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Leclerc
authors.affiliation: Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Université Laval, Québec, QC, Canada.|Département Obstétrique, Gynécologie et Reproduction, Faculté de Médecine, Université Laval, Québec, QC, Canada.
authors.forename: R
authors.initials: R
authors.lastname: Sullivan
authors.affiliation: Boviteq, Saint-Hyacinthe, QC, Canada.
authors.forename: P
authors.initials: P
authors.lastname: Blondin
authors.affiliation: Boviteq, Saint-Hyacinthe, QC, Canada.
authors.forename: C
authors.initials: C
authors.lastname: Vigneault
authors.affiliation: Centre de Recherche en Reproduction, Développement et Santé Intergénérationnelle, Université Laval, Québec, QC, Canada.|Département des Sciences Animales, Faculté des Sciences de L'agriculture et de L'alimentation, Université Laval, Québec, QC, Canada.
authors.forename: F J
authors.initials: FJ
authors.lastname: Richard
mesh_terms: D020101:Acrosome Reaction / Q000187:drug effects; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002417:Cattle; D004822:Epididymis / Q000166:cytology / Q000378:metabolism; D008297:Male; D010208:Papaverine / Q000494:pharmacology*; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism*; D010766:Phosphorylation; D015398:Signal Transduction / Q000187:drug effects / Q000502:physiology; D013094:Spermatozoa / Q000187:drug effects / Q000201:enzymology*
chemical_list: D010208:Papaverine; D010727:Phosphoric Diester Hydrolases; D002118:Calcium
keywords: 
  cAMP
  ; cAMP-PDE; protein phosphorylation; sperm function; spermatozoa