Document Detail


Role of extracellular UTP in the release of uracil from vasoconstricted hindlimb.
MedLine Citation:
PMID:  8430851     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
The source and function of elevated uracil release during vasoconstriction in the perfused rat hindlimb was investigated. The possibility that uracil release derived from the breakdown of released vasoactive uridine 5'-triphosphate (UTP) was examined. Exogenous UTP was found to be a potent vasodilator in the perfused rat hindlimb, opposing norepinephrine and angiotensin-induced increases in vasoconstriction and oxygen consumption. UTP was rapidly catabolized by the hindlimb to uridine 5'-monophosphate (UMP), uridine, and uracil, which were all devoid of vasoactivity. UTP was similarly catabolized by incubated rat aorta. Degradation of exogenous UTP by perfused hindlimb or aorta was inhibited by alpha, beta-methylene-adenosine 5'-diphosphate (AMP-CP), an inhibitor of ectonucleotidases. However, AMP-CP did not decrease uracil and uridine output by the hindlimb during angiotensin-mediated vasoconstriction and increased oxygen consumption. In particular, simultaneous infusion of AMP-CP with angiotensin did not increase efflux of UMP. Although exogenous UTP is a potent vasodilator in the perfused rat hindlimb, it appears not to be released intact during vasoconstriction. Hence, extracellular UTP is unlikely to be the precursor of the uracil release.
Authors:
S M Richards; K A Dora; S Rattigan; E Q Colquhoun; M G Clark
Publication Detail:
Type:  Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  The American journal of physiology     Volume:  264     ISSN:  0002-9513     ISO Abbreviation:  Am. J. Physiol.     Publication Date:  1993 Jan 
Date Detail:
Created Date:  1993-03-05     Completed Date:  1993-03-05     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0370511     Medline TA:  Am J Physiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  H233-7     Citation Subset:  IM    
Affiliation:
Department of Biochemistry, University of Tasmania, Hobart, Australia.
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MeSH Terms
Descriptor/Qualifier:
Adenosine Diphosphate / pharmacology
Adenosine Triphosphate / pharmacology
Animals
Aorta / metabolism
Blood Pressure / drug effects
Extracellular Space / metabolism*
Hindlimb / blood supply
Male
Muscle, Smooth, Vascular / metabolism*
Nucleotides / metabolism
Oxygen Consumption / drug effects
Rats
Rats, Wistar
Uracil / metabolism*
Uridine Monophosphate / antagonists & inhibitors,  metabolism
Uridine Triphosphate / metabolism*,  pharmacology
Vasoconstriction*
Chemical
Reg. No./Substance:
0/Nucleotides; 3805-37-6/adenosine 2',5'-diphosphate; 56-65-5/Adenosine Triphosphate; 58-64-0/Adenosine Diphosphate; 58-97-9/Uridine Monophosphate; 63-39-8/Uridine Triphosphate; 66-22-8/Uracil

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


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