Acidification of the male reproductive tract by a proton pumping (H+)-ATPase

Nat Med. 1996 Apr;2(4):470-2. doi: 10.1038/nm0496-470.


An acidic luminal pH (ref. 1-3) is involved in sperm maturation, and in maintaining sperm in an immotile state in the epididymis and vas deferens (2,4-6). Neutralization by prostatic fluid is one of a complex series of events that triggers sperm motility (2,7,8). Failure of the acidification mechanism might, therefore, result in poor sperm maturation, premature motility and infertility. We have shown that a vacuolar (H+)-ATPase is expressed at high levels on the luminal plasma membrane of specialized cells in the epididymis (9), which closely resemble acid-secreting kidney intercalated cells (10,11). We now show that similar cells are also present in the vas deferens, and that a bafilomycin-sensitive proton flux can be detected using a noninvasive proton-selective vibrating probe. Up to 80% of the net proton secretion in the vas deferens is inhibited by bafilomycin, consistent with a major role of a vacuolar-type (H+)-ATPase in this process. This acidification mechanism is a potential target for novel strategies aimed at modulating the acidification capacity of parts of the male reproductive tract and, therefore, in regulating male fertility.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Anti-Bacterial Agents / pharmacology
  • Hydrogen-Ion Concentration
  • Macrolides*
  • Male
  • Proton Pumps / drug effects
  • Proton Pumps / physiology*
  • Proton-Translocating ATPases / physiology*
  • Rats
  • Rats, Sprague-Dawley
  • Sperm Maturation*
  • Vas Deferens / physiology*


  • Anti-Bacterial Agents
  • Macrolides
  • Proton Pumps
  • bafilomycin A
  • Proton-Translocating ATPases