Linked Life Data

2045147

Source:http://linkedlifedata.com/resource/pubmed/id/2045147

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6 Pt 2
pubmed:dateCreated
1991-7-12
pubmed:abstractText
We assessed the responsiveness of rat juxtamedullary afferent arterioles to purinergic stimulation using the in vitro blood-perfused juxtamedullary nephron technique combined with videomicroscopy to allow direct measurement of arteriolar inside diameter. To minimize the contribution of endogenously formed angiotensin II, all rats were pretreated with enalaprilat (2 mg i.v.) for 30 minutes before the right kidney was isolated and prepared for study. Renal perfusion pressure was set at 110 mm Hg and held constant. Afferent arteriolar diameter averaged 20.9 +/- 0.8 microns (n = 41) under control conditions. Exposure to 1.0 microM 2-chloroadenosine induced a significant (11.1 +/- 3.2%) reduction in vessel diameter, whereas a 100 microM concentration induced an afferent vasodilation (7.6 +/- 1.5%; p less than 0.05). These data are consistent with the preferential stimulation of high affinity constrictor adenosine receptors (A1) at lower concentrations and activation of lower affinity vasodilator adenosine receptors (A2) at higher concentrations. In contrast, ATP elicited a significant afferent vasoconstriction of approximately 9.2%, 12.9%, and 10.0% at concentrations in the range of 1-100 microM (p less than 0.05). Treatment with ADP, at concentrations up to 100 microM, failed to alter vessel caliber significantly. Furthermore, the nonhydrolyzable ATP analogue alpha,beta-methylene ATP produced a rapid and potent vasoconstriction, which mimicked the response to ATP. These data reveal the presence of both adenosine-sensitive P1 and ATP-sensitive P2 purinergic receptors on rat juxtamedullary afferent arterioles and demonstrate that ATP can induce afferent arteriolar vasoconstriction directly without first requiring hydrolysis to adenosine.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0194-911X
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1033-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Juxtamedullary afferent arteriolar responses to P1 and P2 purinergic stimulation.
pubmed:affiliation
Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, Non-U.S. Gov't