Cell pH and H+ Secretion by S3 Segment of Mammalian Kidney: Role of H+-ATPase and Cl−

Cell pH and H+ Secretion by S3 Segment of Mammalian Kidney: Role of H+-ATPase and Cl− The role of H+-ATPase in proximal tubule cell pH regulation was studied by microperfusion techniques and by confocal microscopy. In a first series of experiments, proximal S3 segments of rabbit kidney were perfused ``in vitro'' while their cell pH was measured by fluorescence microscopy after loading with BCECF. In Na+- and Cl−-free medium, cell pH fell by a mean of 0.37 ± 0.051 pH units, but after a few minutes started to rise again slowly. This rise was of 0.17 ± 0.022 pH units per min, and was significantly reduced by bafilomycin and by the Cl− channel blocker NPPB, but not by DIDS. In a second series of experiments, subcellular vesicles of proximal tubule cells of S3 segments of mouse kidney were studied by confocal microscopy after visualization by acridine orange or by Lucifer yellow. After superfusion with low Na+ solution, which is expected to cause cell acidification, vesicles originally disposed in the basolateral and perinuclear cell areas, moved toward the apical area, as detected by changes in fluorescence density measured by the NIH Image program. The variation of apical to basolateral fluorescence ratios during superfusion with NaCl Ringer with time was 0.0018 ± 0.0021 min−1, not significantly different from zero (P > 0.42). For superfusion with Na+0 Ringer, this variation was 0.081 ± 0.015 min−1, P < 0.001 against 0. These slopes were markedly reduced by the Cl− channel blocker NPPB, and by vanadate at a concentration that has been shown to disrupt cytoskeleton function. These data show that the delayed alkalinization of proximal tubule cells in Na+-free medium is probably due to a vacuolar H+-ATPase, whose activity is stimulated in the presence of Cl−, and dependent on apical insertion of subcellular vesicles. The movement of these vesicles is also dependent on Cl− and on the integrity of the cytoskeleton. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The Journal of Membrane Biology Springer Journals

Cell pH and H+ Secretion by S3 Segment of Mammalian Kidney: Role of H+-ATPase and Cl−

Loading next page...
 
/lp/springer_journal/cell-ph-and-h-secretion-by-s3-segment-of-mammalian-kidney-role-of-h-ibzPlTcEgK
Publisher
Springer-Verlag
Copyright
Copyright © Inc. by 2000 Springer-Verlag New York
Subject
Life Sciences; Biochemistry, general; Human Physiology
ISSN
0022-2631
eISSN
1432-1424
D.O.I.
10.1007/s002320010019
Publisher site
See Article on Publisher Site

There are no references for this article.

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

Monthly Plan

  • Read unlimited articles
  • Personalized recommendations
  • No expiration
  • Print 20 pages per month
  • 20% off on PDF purchases
  • Organize your research
  • Get updates on your journals and topic searches

$49/month

Start Free Trial

14-day Free Trial

Best Deal — 39% off

Annual Plan

  • All the features of the Professional Plan, but for 39% off!
  • Billed annually
  • No expiration
  • For the normal price of 10 articles elsewhere, you get one full year of unlimited access to articles.

$588

$360/year

billed annually
Start Free Trial

14-day Free Trial