title: Porcine vas deferens luminal pH is acutely increased by systemic xylazine administration.
abstract: Data are accumulating to demonstrate that pH regulation in the male reproductive tract has a vital role in modulating sperm cell fertilizing capacity, and therefore male fertility. Bicarbonate uptake by sperm cells is required for the achievement of motility levels required for fertilization. Vas deferens epithelial cells can carry out measurable bicarbonate secretion, but the available literature to date reports that the vas deferens luminal content is typically acidic. This study aimed to determine pH in the boar vas deferens lumen and whether modulatory mechanisms exist for regulation of pH in this compartment of the male reproductive tract. A fiberoptic pH probe was used to assess pH in the vas deferens of anesthetized adult boars. The mean pH, derived from multiple measurements at variable positions along the vas deferens lumen, was 7.39 +/- 0.09. Furthermore, administration of xylazine, an alpha-2 adrenergic receptor agonist rapidly (<10 min) alkalinized the vas deferens lumen in most cases. Because the duct was transected proximal to the site of measurements, the observations rule out the possibility that alkalinization resulted from secretion in more proximal portions of the duct. These results indicate that the boar vas deferens lumen can be alkaline, and they suggest that porcine vas deferens epithelia increase net bicarbonate secretion in vivo after systemic alpha-2 adrenergic stimulation. This secretory response greatly changes the luminal environment to which sperm cells are exposed, which will initiate or enhance motility, and is expected to modulate male fertility.
authors.affiliation: Department of Anatomy & Physiology, Kansas State University, Manhattan, Kansas 66506, USA. falves@vet.ksu.edu
authors.forename: Fernando
authors.initials: F
authors.lastname: Pierucci-Alves
authors.forename: Cameron L
authors.initials: CL
authors.lastname: Duncan
authors.forename: James D
authors.initials: JD
authors.lastname: Lillich
authors.forename: Bruce D
authors.initials: BD
authors.lastname: Schultz
mesh_terms: D000316:Adrenergic alpha-Agonists; D000818:Animals; D006863:Hydrogen-Ion Concentration; D008297:Male; D013552:Swine; D014649:Vas Deferens / Q000378:metabolism*; D014991:Xylazine
chemical_list: D000316:Adrenergic alpha-Agonists; D014991:Xylazine
references.citation: Int J Androl. 1990 Jun;13(3):238-43
references.pmid: 2387644
references.citation: Mol Reprod Dev. 2000 Feb;55(2):125-35
references.pmid: 10618651
references.citation: Hum Mol Genet. 1993 Oct;2(10):1561-9
references.pmid: 7505691
references.citation: Fertil Steril. 2006 Jan;85(1):232-5
references.pmid: 16412765
references.citation: Reproduction. 2003 Feb;125(2):233-40
references.pmid: 12578537
references.citation: J Physiol. 1971 Mar;213(3):557-70
references.pmid: 5551402
references.citation: Biol Reprod. 2003 Mar;68(3):1027-34
references.pmid: 12604657
references.citation: Am J Physiol Cell Physiol. 2006 Jun;290(6):C1560-71
references.pmid: 16421205
references.citation: Proc Natl Acad Sci U S A. 2007 Jun 5;104(23):9816-21
references.pmid: 17519339
references.citation: EMBO J. 2006 Sep 6;25(17):4131-41
references.pmid: 16932748
references.citation: Nat Med. 1996 Apr;2(4):470-2
references.pmid: 8597961
references.citation: Biol Reprod. 2001 Jun;64(6):1699-707
references.pmid: 11369598
references.citation: J Urol. 1994 Sep;152(3):899-901
references.pmid: 8051748
references.citation: Urology. 2002 Mar;59(3):424-7
references.pmid: 11880085
references.citation: J Androl. 2003 May-Jun;24(3):361-3
references.pmid: 12721211
references.citation: J Androl. 1997 Nov-Dec;18(6):623-36
references.pmid: 9432135
references.citation: Am J Physiol Cell Physiol. 2002 Oct;283(4):C1033-44
references.pmid: 12225967
references.citation: Am J Respir Crit Care Med. 1995 Mar;151(3 Pt 2):S59-64
references.pmid: 7533607
references.citation: Biol Reprod. 2002 Apr;66(4):1016-23
references.pmid: 11906921