Document Detail


Effects of activation of vasopressin-V1-receptors on regional kidney blood flow and glomerular arteriole diameters.
MedLine Citation:
PMID:  11327642     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
OBJECTIVES: We tested whether vasoconstriction of juxtamedullary glomerular arterioles contributes to vasopressin V1 -receptor-mediated reductions in medullary perfusion (MBF). DESIGN AND METHODS: The left kidney of pentobarbitone anaesthetized rabbits was denervated, a perivascular flow probe placed around the renal artery and laser-Doppler flow probes positioned in the inner medulla and on the cortical surface. Rabbits then received a 30 min intravenous infusion of [Phe2,Ile3,Orn8]vasopressin (V1 -AG; 30 ng/kg per min; n = 7) or its vehicle (n = 7). Kidneys were perfusion fixed at the final recorded mean arterial pressure (MAP) and filled with methacrylate casting material. Diameters of afferent and efferent arterioles were determined by scanning electron microscopy. RESULTS: V1 -AG increased MAP (19 +/- 3%) and reduced MBF (30 +/- 8%) but not cortical perfusion or total renal blood flow. Vehicle-treatment did not significantly affect these variables. After vehicle- and V1-AG-treatment, juxtamedullary afferent arteriole luminal diameter averaged 15.35 +/- 1.31 and 15.88 +/- 1.86 microm, respectively (P= 0.92), while juxtamedullary efferent arteriole luminal diameter averaged 17.75 +/- 1.86 and 18.36 +/- 2.24 microm, respectively (P= 0.93). CONCLUSIONS: V1-AG reduced MBF but did not significantly affect juxtamedullary arteriolar diameter. Our results therefore do not support a role for juxtamedullary arterioles in producing V1-receptor-mediated reductions in MBF, suggesting that downstream vascular elements (e.g. outer medullary descending vasa recta) might be involved.
Authors:
A G Correia; K M Denton; R G Evans
Publication Detail:
Type:  In Vitro; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  Journal of hypertension     Volume:  19     ISSN:  0263-6352     ISO Abbreviation:  J. Hypertens.     Publication Date:  2001 Mar 
Date Detail:
Created Date:  2001-04-30     Completed Date:  2001-08-23     Revised Date:  2007-11-15    
Medline Journal Info:
Nlm Unique ID:  8306882     Medline TA:  J Hypertens     Country:  England    
Other Details:
Languages:  eng     Pagination:  649-57     Citation Subset:  IM    
Affiliation:
Department of Physiology, Monash University, Victoria, Australia.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Animals
Arterioles / physiology
Hemodynamics / drug effects
Kidney / drug effects
Kidney Glomerulus / blood supply*
Male
Ornipressin / analogs & derivatives,  pharmacology*
Rabbits
Receptors, Vasopressin / agonists,  physiology*
Reference Values
Renal Circulation / physiology*
Vasoconstriction / physiology*
Chemical
Reg. No./Substance:
0/Receptors, Vasopressin; 0/vasopressin, Phe(2)-Ile(3)-Orn(8)-; 3397-23-7/Ornipressin

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


Previous Document:  Flow-mediated dilatation of the brachial artery and left ventricular geometry in hypertensive patien...
Next Document:  Effects of the ET(A)/ET(B) antagonist, TAK-044, on blood pressure and renal excretory function after...