Author:
Yu Ming,Lopez Bernardo,Dos Santos Elisabete A.,Falck John R.,Roman Richard J.
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, and86Rb+uptake, an index of Na+transport, in mTALH isolated from rats. Ouabain (2 mM) increased, whereas furosemide (100 μM) decreased, [Na+]iin the mTALH of rats. Ouabain and furosemide inhibited86Rb+uptake by 91 and 30%, respectively. 20-HETE (1 μM) had a similar effect as ouabain and increased [Na+]ifrom 19 ± 1 to 30 ± 1 mM. 20-HETE reduced Na+-K+-ATPase activity by 30% and86Rb+uptake by 37%, but it had no effect on86Rb+uptake or [Na+]iin the mTALH of rats pretreated with ouabain. 20-HETE inhibited86Rb+uptake by 12% and increased [Na+]iby 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.
Publisher
American Physiological Society
Subject
Physiology (medical),Physiology
Reference40 articles.
1. Elevated heart rate variability in physically active postmenopausal women: a cardioprotective effect?
2. Beltowski J, Marciniak A, Wojcicka G, Gorny D.The opposite effects of cyclic AMP-protein kinase a signal transduction pathway on renal cortical and medullary Na+,K+-ATPase activity.J Physiol Pharmacol53: 211–231, 2002.
3. cAMP-dependent control of Na+/H+ antiport by AVP, PTH, and PGE2 in rat medullary thick ascending limb cells
4. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding
5. Elevated [Cl-]i, and [Na+]i inhibit Na+, K+, Cl- cotransport by different mechanisms in squid giant axons.
Cited by
43 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献