P2Y2 Receptor-mediated Inhibition of Amiloride-sensitive Short Circuit Current in M-1 Mouse Cortical Collecting Duct Cells

P2Y2 Receptor-mediated Inhibition of Amiloride-sensitive Short Circuit Current in M-1 Mouse... Extracellular nucleotides modulate renal ion transport. Our previous results in M-1 cortical collecting duct cells indicate that luminal and basolateral ATP via P2Y2 receptors stimulate luminal Ca2+-activated Cl− channels and inhibit Na+ transport. Here we address the mechanism of ATP-mediated inhibition of Na+ transport. M-1 cells had a transepithelial voltage (V te ) of −31.4 ± 1.3 mV and a transepithelial resistance (R te ) of 1151 ± 28 Ωcm2. The amiloride-sensitive short circuit current (I sc ) was −28.0 ± 1.1 μA/cm2. The ATP-mediated activation of Cl− channels was inhibited when cytosolic Ca2+ increases were blocked with cyclopiazonic acid (CPA). Without CPA the ATP-induced [Ca2+]i increase was paralleled by a rapid and transient R te decrease (297 ± 51 Ωcm2). In the presence of CPA, basolateral ATP led to an R te increase by 144 ± 17 Ωcm2 and decreased V te from −31 ± 2.6 to −26.6 ± 2.5 mV. I sc dropped from −28.6 ± 2.4 to −21.6 ± 1.9 μA/cm2. Similar effects were observed with luminal ATP. In the presence of amiloride, ATP was without effect. This reflects ATP-mediated inhibition of Na+ absorption. Lowering [Ca2+]i by removal of extracellular Ca2+ did not alter the ATP effect. PKC inhibition or activation were without effect. Na+ absorption was activated by pHi alkalinization and inhibited by pHi acidification. ATP slightly acidified M-1 cells by 0.05 ± 0.005 pH units, quantitatively not explaining the ATP-induced effect. In summary this indicates that extracellular ATP via luminal and basolateral P2Y2 receptors inhibits Na+ absorption. This effect is not mediated via [Ca2+]i, does not involve PKC and is to a small part mediated via intracellular acidification. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png The Journal of Membrane Biology Springer Journals

P2Y2 Receptor-mediated Inhibition of Amiloride-sensitive Short Circuit Current in M-1 Mouse Cortical Collecting Duct Cells

Loading next page...
 
/lp/springer_journal/p2y2-receptor-mediated-inhibition-of-amiloride-sensitive-short-circuit-ZgsiFcWCtx
Publisher
Springer-Verlag
Copyright
Copyright © Inc. by 2001 Springer-Verlag New York
Subject
Life Sciences; Biochemistry, general; Human Physiology
ISSN
0022-2631
eISSN
1432-1424
D.O.I.
10.1007/s00232-001-0059-4
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