title: Expression of two-pore domain potassium channels in nonhuman primate sperm.
abstract: OBJECTIVE
  Two-pore domain potassium channels (K(2P)) play integral roles in cell signaling pathways by modifying cell membrane resting potential. Here we describe the expression and function of K(2P) channels in nonhuman primate sperm.
  
  
  METHODS
  Experimental animal study, randomized blinded concentration-response experiments.
  
  
  METHODS
  University-affiliated primate research center.
  
  
  METHODS
  Male nonhuman primates.
  
  
  METHODS
  Western blot and immunofluorescent analysis of epididymal sperm samples. Kinematic measures (curvilinear velocity and lateral head displacement) and acrosome status were studied in epididymal sperm samples exposed to K(2P) agonist (docosahexaenoic acid) and antagonist (gadolinium).
  
  
  METHODS
  Semiquantitative protein expression and cellular localization and quantitative changes in specific kinematic parameters and acrosome integrity.
  
  
  RESULTS
  Molecular analysis demonstrated expression and specific regional distribution of TRAAK, TREK-1, and TASK-2 in nonhuman primate sperm. Docosahexaenoic acid produced a concentration-dependent increase in curvilinear velocity (P<.0001) with concomitant concentration-dependent reductions in lateral head displacement (P=.005). Gadolinium reduced velocity measures (P<.01) without significantly affecting lateral head displacement.
  
  
  CONCLUSIONS
  The results demonstrated expression and function of K(2P) potassium channels in nonhuman primate sperm for the first time. The unique, discrete distributions of K(2P) channels in nonhuman primate sperm suggest specific roles for this subfamily of ion channels in primate sperm function.
authors.affiliation: Washington National Primate Research Center, University of Washington, Seattle, Washington, USA.
authors.forename: Gregory E
authors.initials: GE
authors.lastname: Chow
authors.forename: Charles H
authors.initials: CH
authors.lastname: Muller
authors.forename: Eliza C
authors.initials: EC
authors.lastname: Curnow
authors.forename: Eric S
authors.initials: ES
authors.lastname: Hayes
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D015870:Gene Expression / Q000502:physiology; D020869:Gene Expression Profiling; D006801:Humans; D008254:Macaca nemestrina; D008297:Male; D016062:Porosity; D015221:Potassium Channels / Q000378:metabolism*; D024683:Potassium Channels, Tandem Pore Domain / Q000378:metabolism*; D017434:Protein Structure, Tertiary; D013094:Spermatozoa / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: C410295:KCNK5 protein, human; C503433:Kcnk4 protein, mouse; D015221:Potassium Channels; D024683:Potassium Channels, Tandem Pore Domain; C103742:potassium channel protein TREK-1