Biphasic Vasoconstriction of the Rabbit Ear Artery
- 1 January 1973
- journal article
- research article
- Published by Wolters Kluwer Health in Circulation Research
- Vol. 32 (1), 49-58
- https://doi.org/10.1161/01.res.32.1.49
Abstract
Sympathetic nerve stimulation and intraluminal norepinephrine infusion for more than 15 seconds produced a biphasic response in the isolated rabbit ear artery perfused with Krebs solution. This response consisted of an initial rapid constriction (phase A), which was followed by partial relaxation, and a final slowly developing constriction (phase B), which lasted for the duration of nerve stimulation or norepinephrine administration. Raising the potassium concentration of the Krebs solution to 12mM decreased the relaxation time between the two constrictor phases in response to norepinephrine; lowering the potassium concentration to 1.2 mM increased the relaxation time and decreased the degree of constriction of both phases. Biphasic vasoconstrictor responses were also elicited by the intraluminal infusion of phenylephrine, histamine, serotonin, or 35 mM potassium. When calcium was absent from the perfusing solution or when manganous sulfate (1mM) was present, norepinephrine produced only a fast phase A constriction, with no subsequent slow phase B constriction. However, after treatment of the artery with ryanodine, the phase A constriction in response to norepinephrine was markedly inhibited, but the phase B constriction was not. We concluded that the fast phase A constriction depends on the release of calcium from an intracellular pool and that the slow phase B constriction depends on the influx of extracellular calcium.Keywords
This publication has 10 references indexed in Scilit:
- Manganese on Calcium Flux and Norepinephrine-Induced Tension in Arterial Smooth MuscleExperimental Biology and Medicine, 1972
- Strontium Accumulation by Sarcoplasmic Reticulum and Mitochondria in Vascular Smooth MuscleScience, 1971
- Biphasic Constrictor Response of the Rabbit Ear ArteryCirculation Research, 1971
- Ca and Na interaction in vascular smooth muscle contractionAmerican Journal of Physiology-Legacy Content, 1971
- Mechanism of the Woodworth staircase phenomenon in heart and skeletal muscleAmerican Journal of Physiology-Legacy Content, 1969
- Calcium pools utilized for contraction in smooth muscleAmerican Journal of Physiology-Legacy Content, 1967
- THE INFLUENCE OF SYMPATHETIC INNERVATION ON VASCULAR SENSITIVITY TO NORADRENALINEBritish Journal of Pharmacology and Chemotherapy, 1967
- A SIMPLE ISOLATED NERVE‐BLOOD VESSEL PREPARATIONImmunology & Cell Biology, 1965
- Action potentials of guinea pig atria under conditions which alter contractionAmerican Journal of Physiology-Legacy Content, 1964
- Vascular Smooth Muscle: Dual Effect of CalciumScience, 1963