Faculty Collaboration Database

Urotensin II is a nitric oxide-dependent vasodilator and natriuretic peptide in the rat kidney. Am J Physiol Renal Physiol 2003 Oct;285(4):F792-8

Date

06/05/2003

Pubmed ID

12783779

DOI

10.1152/ajprenal.00342.2002

Scopus ID

2-s2.0-0141590352 (requires institutional sign-in at Scopus site)   97 Citations

Abstract

Recent studies have indicated that urotensin II (UII), a cyclic peptide, is vasoactive and may be involved in cardiovascular dysfunctions. It remains unknown, however, whether UII plays a role in the control of renal vascular tone and tubular function. In the present study, a continuous infusion of synthetic human UII (hUII) into the renal artery (RA) in anesthetized rats was found to increase renal blood flow (RBF) and urinary water and sodium excretion (UV and UNaV) in a dose-dependent manner. At a dose of 20 ng. kg-1. min-1, it increased RBF by 20% and UV and UNaV by 94 and 109%, respectively. Nitric oxide (NO) synthase inhibitor NG-nitro-l-arginine methyl ester (l-NAME) completely abolished hUII-induced increases in RBF and water/sodium excretion. In isolated, pressurized, and phenylephrine-precontracted small RA with internal diameter of approximately 200 microm, hUII produced a concentration-dependent vasodilation with a maximal response of 55% at 1.5 microM. l-NAME significantly blocked this hUII-induced vasodilation by 60%. In denuded RA, hUII had neither vasodilator nor vasoconstrictor effect. With the use of 4,5-diaminofluorescein diacetate-based fluorescence imaging analysis of NO levels, hUII (1 microM) was shown to double the NO levels within the endothelium of freshly dissected small RA, and l-NAME blocked this UII-induced production of endothelial NO. These results indicate that UII produces vasodilator and natriuretic effects in the kidney and that UII-induced vasodilation is associated with increased endothelial NO in the RA.

Author List

Zhang AY, Chen YF, Zhang DX, Yi FX, Qi J, Andrade-Gordon P, de Garavilla L, Li PL, Zou AP

Author

David X. Zhang MD, PhD Associate Professor in the Medicine department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
Blood Pressure
Endothelium, Vascular
Glomerular Filtration Rate
Humans
In Vitro Techniques
Kidney
Male
Natriuretic Agents
Nitric Oxide
Rats
Rats, Sprague-Dawley
Renal Artery
Renal Circulation
Urotensins
Vasodilation
Vasodilator Agents