Document Detail


Hypoxia- and endothelium-mediated changes in the pharmacological responsiveness of circumflex coronary artery rings from the sheep.
MedLine Citation:
PMID:  2472846     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
1. The role(s) of the endothelium in modulating the responsiveness of isolated circumflex coronary artery rings (o.d. = 2.0-2.5 mm and o.d. = 0.6-1.3 mm) from sheep was investigated under oxygenated and hypoxic conditions. 2. Removal of the endothelium abolished the contraction produced by lowering the PO2 from 620 to 8 mmHg (either under optimal resting tension or precontracted by 40 mM KCl). In denuded artery rings sudden hypoxia caused relaxation. 3. Under oxygenated conditions, removal of the endothelium augmented the vasoconstrictor effects of U46619, 5-hydroxytryptamine (5-HT) and K+. In the denuded artery rings, hypoxia abolished the contractile effects of U46619 and reduced the contractile effects of 5-HT and K+. 4. Under oxygenated conditions, the vasorelaxant effect of adenosine was depressed by removal of the endothelium. In endothelium-denuded preparations, the small relaxant effect of adenosine remaining was greatly potentiated. 5. Haemolysate (1 microliter ml-1) caused an endothelium-dependent contraction under oxygenated conditions. The hypoxic contraction observed in the artery ring under resting tension was significantly potentiated by haemolysate (1 microliter ml-1). Haemolysate 1 microliter ml-1 had no effect on the denuded artery rings under hypoxic conditions. 6. Haemolysate (1 microliter ml-1) potentiated the vasoconstrictor effects of U46619 (0.5 microM), 5-HT (1 microM) and K+ (24 mM) under oxygenated conditions. 7. These results indicate that endothelium profoundly modifies the effect of hypoxia on the responsiveness of sheep isolated left circumflex coronary artery rings.
Authors:
Y W Kwan; R M Wadsworth; K A Kane
Related Documents :
15970446 - Evidence of a decrease in nitric oxide-storage molecules following acute hypoxia and/or...
7961246 - Effect of dopamine on hypoxic ventilatory response of sedated piglets with intact and d...
14561236 - Effects of hypoxia on the circadian patterns in men.
7680496 - Potentiation by hypoxia of contractions caused by angiotensin ii in dog and monkey cere...
8733096 - Factors of importance to doppler indices of left ventricular filling in 50-year-old hea...
24084216 - Atrophic cardiomyocyte signaling in hypertensive heart disease.
Publication Detail:
Type:  In Vitro; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  British journal of pharmacology     Volume:  96     ISSN:  0007-1188     ISO Abbreviation:  Br. J. Pharmacol.     Publication Date:  1989 Apr 
Date Detail:
Created Date:  1989-08-18     Completed Date:  1989-08-18     Revised Date:  2009-11-18    
Medline Journal Info:
Nlm Unique ID:  7502536     Medline TA:  Br J Pharmacol     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  857-63     Citation Subset:  IM    
Affiliation:
Department of Physiology and Pharmacology, University of Strathclyde, Glasgow.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid
Adenosine / pharmacology
Animals
Anoxia / physiopathology*
Cats
Coronary Vessels / drug effects
Endothelium, Vascular / physiology*
Hemolysis
Isometric Contraction / drug effects
Muscle, Smooth, Vascular / drug effects*
Nitroprusside / pharmacology
Potassium / pharmacology
Prostaglandin Endoperoxides, Synthetic / pharmacology
Serotonin / pharmacology
Sheep
Substance P / pharmacology
Vasoconstrictor Agents / pharmacology
Chemical
Reg. No./Substance:
0/Prostaglandin Endoperoxides, Synthetic; 0/Vasoconstrictor Agents; 15078-28-1/Nitroprusside; 33507-63-0/Substance P; 50-67-9/Serotonin; 58-61-7/Adenosine; 7440-09-7/Potassium; 76898-47-0/15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5,13-dienoic Acid
Comments/Corrections

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


Previous Document:  Evidence that the hypertrophic action of clenbuterol on denervated rat muscle is not propranolol-sen...
Next Document:  Differential antagonism of the negative inotropic effect of gentamicin by calcium ions, Bay K 8644 a...