ISSN:
0899-0042
Keywords:
renal vasodilation
;
dopamine agonists
;
dopamine antagonists
;
blood pressure
;
Chemistry
;
Organic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Fenoldopam (SK&F 82526) is a potent and selective dopamine DA-1 agonist with demonstrated renal vasodilator and antihypertensive activities in experimental animals and humans. Fenoldopam is a racemic mixture of two enantiomers, SK&F R-82526 and SK&F S-82526. The R-enantiomer is uniformly reported to be more potent than the racemate; in contrast, there is controversy regarding potency of the S-enantiomer. In these studies, the renal and systemic hemodynamic activities of fenoldopam and its enantiomers are characterized in anesthetized, phenoxybenzamine-treated dogs. The results show that the renal and systemic vasodilator activities of fenoldopam are properties of the R-enantiomer; the S-enantiomer is essentially inactive. The renal and systemic vasodilator properties of SK&F R-82526 are antagonized in a competitive fashion by the DA-1 antagonist, SK&F R-83566, but not the DA-2 antagonist, domperidone. Ganglionic blockade did not attenuate renal vasodilation associated with SK&F R-82526. Thus, the mechanism of SK&F R-82526-associated vasodilation, like that previously established for fenoldopam, is via stimulation of postganglionic DA-1 receptors.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/chir.530020405
