Effects of 20-HETE on Na+ transport and Na+-K +-ATPase activity in the thick ascending loop of Henle

Ming Yu, Bernardo Lopez, Elisabete A. Dos Santos, John R. Falck, Richard J. Roman

Research output: Contribution to journalArticle

38 Scopus citations

Abstract

Previous studies have indicated that 20-hydroxyeicosatetraenoic acid (20-HETE) inhibits Na+ transport in the medullary thick ascending loop of Henle (mTALH), but the mechanisms involved remain uncertain. The present study compared the effects of 20-HETE with those of ouabain and furosemide on intracellular Na+ concentration ([Na+]i), Na+-K+-ATPase activity, and 86Rb+ uptake, an index of Na+ transport, in mTALH isolated from rats. Ouabain (2 mM) increased, whereas furosemide (100 μM) decreased, [Na +]i in the mTALH of rats. Ouabain and furosemide inhibited 86Rb+ uptake by 91 and 30%, respectively. 20-HETE (1 μM) had a similar effect as ouabain and increased [Na+] i from 19 ± 1 to 30 ± 1 mM. 20-HETE reduced Na +-K+-ATPase activity by 30% and 86Rb + uptake by 37%, but it had no effect on 86Rb+ uptake or [Na+]i in the mTALH of rats pretreated with ouabain. 20-HETE inhibited 86Rb+ uptake by 12% and increased [Na+]i by 19 mM in mTALH pretreated with furosemide. These findings indicate that 20-HETE secondarily inhibits Na + transport in the mTALH of the rat, at least, in part by inhibiting the Na+-K+-ATPase activity and raising [Na +]i.

Original languageEnglish (US)
Pages (from-to)R2400-R2405
JournalAmerican Journal of Physiology - Regulatory Integrative and Comparative Physiology
Volume292
Issue number6
DOIs
StatePublished - Jun 2007

Keywords

  • 20-hydroxyeicosatetraenoic acid
  • Cytochrome P-4504A
  • Kidney
  • Medullary thick ascending loop of Henle
  • Rat
  • Sodium-potassium- adenosinetriphosphatase

ASJC Scopus subject areas

  • Physiology
  • Physiology (medical)

Fingerprint Dive into the research topics of 'Effects of 20-HETE on Na<sup>+</sup> transport and Na<sup>+</sup>-K <sup>+</sup>-ATPase activity in the thick ascending loop of Henle'. Together they form a unique fingerprint.

  • Cite this