Tedisamil (KC 8857) differentially inhibits the 86Rb+ efflux-stimulating and vasorelaxant properties of cromakalim.
Tedisamil, a blocker of cardiac K+ channels, potently inhibited cromakalim-induced 86Rb+ efflux from rat aorta with a pIC50 = 7.3, a value similar to that obtained with the sulphonylurea glibenclamide. However, tedisamil was approximately 30 times less potent than glibenclamide in inhibiting the vasorelaxant effects of cromakalim. The data suggest that tedisamil can dissociate between the efflux-inducing and vasorelaxant effects of cromakalim and may therefore prove to be an important tool in elucidating the mechanism of action of this vasorelaxant.
Bray
K
K
Cardiovascular Department, Sandoz Pharma Ltd., Basel, Switzerland.
Quast
U
U
D000818:Animals; D001011:Aorta / Q000187:drug effects; D001578:Benzopyrans / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D001643:Bridged Bicyclo Compounds / Q000494:pharmacology*; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002316:Cardiotonic Agents / Q000494:pharmacology*; D019806:Cromakalim; D003521:Cyclopropanes / Q000494:pharmacology*; D005905:Glyburide / Q000494:pharmacology; D007537:Isometric Contraction / Q000187:drug effects; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000187:drug effects* / Q000378:metabolism; D015221:Potassium Channels / Q000187:drug effects*; D011758:Pyrroles / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D012414:Rubidium Radioisotopes / Q000378:metabolism*; D014665:Vasodilator Agents / Q000494:pharmacology*
D001578:Benzopyrans; D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002316:Cardiotonic Agents; D003521:Cyclopropanes; D015221:Potassium Channels; D011758:Pyrroles; D012414:Rubidium Radioisotopes; D014665:Vasodilator Agents; D019806:Cromakalim; C059921:tedisamil; D005905:Glyburide