Abstract
1 Increases in femoral blood flow were produced by intra-arterial injections of dopamine (5-50 mug) in some but not all anaesthetized dogs studied, following treatment with the alpha-adrenoceptor antagonist, phentolamine. 2 The dilator effect of dopamine was not due to inhibition of adrenergic vasomotor tone as it was not affected by pharmacological procedures which completely abolished the activity of vastomotor nerves. 3 Blockade of vascular beta-adrenoceptors using propanolol reduced the flow increases produced by dopamine much less than it did those produced by isoprenaline. 4 Responses to dopamine were significantly depressed by intra-arterial administration of ergometrine (0.5 mg). This dose of ergometrine did not reduce femoral dilator responses to acetylcholine, histamine, isopienaline, bradykinin, or 5-hydroxytryptamine. 5 It is concluded that the femoral vascular bed in the dog contains specific vasodilator receptors for dopamine. Ergometrine appears to be a selective antagonist of dopamine at these receptors.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bell C., Conway E. L., Lang W. J. Ergometrine and apomorphine as selective antagonists of dopamine in the canine renal vasculature. Br J Pharmacol. 1974 Dec;52(4):591–595. doi: 10.1111/j.1476-5381.1974.tb09728.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- EBLE J. N. A PROPOSED MECHANISM FOR THE DEPRESSOR EFFECT OF DOPAMINE IN THE ANESTHETIZED DOG. J Pharmacol Exp Ther. 1964 Jul;145:64–70. [PubMed] [Google Scholar]
- Goldberg L. I. Cardiovascular and renal actions of dopamine: potential clinical applications. Pharmacol Rev. 1972 Mar;24(1):1–29. [PubMed] [Google Scholar]
- Higgins C. B., Millard R. W., Braunwald E., Vatner S. F. Effects and mechanisms of action of dopamine on regional hemodynamics in the conscious dog. Am J Physiol. 1973 Aug;225(2):432–437. doi: 10.1152/ajplegacy.1973.225.2.432. [DOI] [PubMed] [Google Scholar]
- McNay J. L., Goldberg L. I. Comparison of the effects of dopamine, isoproterenol, norepinephrine and bradykinin on canine renal and femoral blood flow. J Pharmacol Exp Ther. 1966 Jan;151(1):23–31. [PubMed] [Google Scholar]
- Walker R. J., Woodruff G. N., Glaizner B., Sedden C. B., Kerkut G. A. The pharmacology of Helix dopamine receptor of specific neurones in the snail, Helix aspersa. Comp Biochem Physiol. 1968 Feb;24(2):455–469. doi: 10.1016/0010-406x(68)90997-3. [DOI] [PubMed] [Google Scholar]
- Willems J. L., Bogaert M. G. Dopamine-induced neurogenic vasodilatation: antagonism at the vascular level. Arch Int Pharmacodyn Ther. 1973 Jul;204(1):198–199. [PubMed] [Google Scholar]