POTENTIATIVE EFFECTS OF ALPHA-AGONISTIC SYMPATHOMIMETIC AMINES ON VASOCONSTRICTION BY ADRENERGIC-NERVE STIMULATION
- 1 January 1980
- journal article
- research article
- Vol. 215 (2), 377-381
Abstract
The effects of catecholamines and other sympathomimetic amines with .alpha. adrenergic activity on vasoconstriction were studied. Short ring segments were prepared from 5 rabbit blood vessels including the mesoduodenal, brachial, central ear and pulmonary lobar arteries, and the saphenous vein. Constriction was elicited by electrical field stimulation of adrenergic neurons. This reponse was markedly potentiated in the mesenteric preparation by low concentrations of norepinephrine, epinephrine, phenylephrine, methoxamine, naphazoline and oxymetazoline. The potentiation occurred with amine concentrations not sufficient to elevate the spontaneous transmitter release or basal smooth muscle tone. Propranolol, cocaine and metanephrine did not prevent the potentiation. Isoproterenol and dopamine potentiated the response only in high concentrations, and tyrosine was without an effect. An unidentified extraneuronal action was probably responsible for the potentiation. The mesenteric artery was unique for its marked potentiation; the brachial artery was potentiated only slightly and the other 3 vessels were inhibited by the .alpha. adrenergic agents in the constrictor response to stimulation.This publication has 6 references indexed in Scilit:
- Presynaptic receptor systems on cardiac sympathetic nervesLife Sciences, 1979
- EFFECTS OF ADENOSINE-TRIPHOSPHATE AND PROSTAGLANDINS ON VASCULAR ADRENERGIC TRANSMISSION1978
- Presynaptic receptor systems on the noradrenergic neurones of the rabbit pulmonary arteryNaunyn-Schmiedebergs Archiv für experimentelle Pathologie und Pharmakologie, 1977
- THE INHIBITION OF NORADRENALINE UPTAKE BY SYMPATHOMIMETIC AMINES IN THE RAT ISOLATED HEARTBritish Journal of Pharmacology and Chemotherapy, 1965
- Electrical Quiescence of Pulmonary Artery Smooth Muscle During Sympathomimetic StimulationCirculation Research, 1964
- Sensitivity of the Large Blood Vessels of the Rabbit to l -Epinephrine and l -NorepinephrineCirculation Research, 1961