Effect of spironolactone and its metabolites on contractile property of isolated rat aorta rings.

Article Details

Citation

Sorrentino R, Autore G, Cirino G, d'Emmanuele de Villa Bianca R, Calignano A, Vanasia M, Alfieri C, Sorrentino L, Pinto A

Effect of spironolactone and its metabolites on contractile property of isolated rat aorta rings.

J Cardiovasc Pharmacol. 2000 Aug;36(2):230-5.

PubMed ID
10942165 [ View in PubMed
]
Abstract

Spironolactone and its active metabolites canrenone and potassium canrenoate are normally used as antihypertensive drugs. Although they are classified as antagonists of aldosterone, their mechanism of action cannot be ascribed solely to the regulation of ion transport in the distal tubule of nephrons. Here we have evaluated the effects of spironolactone, canrenone, and potassium canrenoate on contractile properties of isolated rat aorta rings. Spironolactone (1-300 microM), canrenone (1-300 microM), and potassium canrenoate (0.01-10 mM), in a concentration-dependent manner, relaxed rat aorta rings precontracted with phenylephrine (1 microM) or KCl (40 mM). These relaxant effects were not affected by prior treatment with either aldosterone (100 microM), glibenclamide (10 microM), or tetraethylammonium (10 mM), excluding the possibility that these drugs can be involved in either the nongenomic effect of aldosterone or on activation of potassium channels. Spironolactone and canrenone at concentrations of 30 and 100 microM, but not at 10 microM, and potassium canrenoate at concentrations of 0.3 and 1 mM, but not at 0.1 mM, significantly inhibited the phenylephrine (0.001-3 microM) concentration-response curve. Conversely, all tested concentrations of spironolactone (10, 30, and 100 microM), canrenone (10, 30, and 100 microM), and potassium canrenoate (0.1, 0.3, and 1 mM) significantly inhibited the concentration-response curve induced by cumulative concentrations of KCI (10-80 mM). Because both phenylephrine- and KCl-induced contractions imply an intracellular Ca2+ influx, we suggest that these drugs could act through an inhibition of voltage-dependent Ca2+ channels.

DrugBank Data that Cites this Article

Drug Targets
DrugTargetKindOrganismPharmacological ActionActions
SpironolactoneVoltage-dependent L-type calcium channel (Protein Group)Protein groupHumans
Unknown
Inhibitor
Details
Drug Interactions
DrugsInteraction
Norepinephrine
Spironolactone
The therapeutic efficacy of Norepinephrine can be decreased when used in combination with Spironolactone.