Abstract |
The present study was designed to test the hypothesis that the vasoconstrictive effects of alpha-adrenergic receptors are responsible, at least in part, for the lack of a maximal vasodilatation of coronary arteries during hemorrhagic shock. Open-chested, anesthetized, mongrel dogs were bled so as to reach an arterial pressure level of 44 mm Hg, and were monitored using an electromagnetic, non-cannulating flowmeter. During shock, two intracoronary injections were made, one of saline, the other of phenoxybenzamine ( Dibenzyline). Control dogs had 2 injections of saline. Following phenoxybenzamine, coronary blood flow increased by 32%. These results indicate that although coronary blood flow may be mainly under local control, the sympathetic nervous system limits maximal coronary vasodilatation during hemorrhagic shock by virtue of activated alpha-adrenergic receptors.
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Authors | F Birinyi, D B Hackel, E Mikat |
Journal | Circulatory shock
(Circ Shock)
Vol. 4
Issue 4
Pg. 297-303
( 1977)
ISSN: 0092-6213 [Print] United States |
PMID | 598003
(Publication Type: Journal Article, Research Support, U.S. Gov't, P.H.S.)
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Chemical References |
- Phenoxybenzamine
- Sodium Chloride
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Topics |
- Animals
- Blood Flow Velocity
- Coronary Circulation
(drug effects)
- Dogs
- Male
- Phenoxybenzamine
(administration & dosage, pharmacology)
- Shock, Hemorrhagic
(physiopathology)
- Sodium Chloride
(administration & dosage)
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