TY - JOUR T1 - Effect of dihydro-ouabain on vascular tone on the perfused cannine hindlimb. JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 255 LP - 261 VL - 199 IS - 1 AU - J A Quest AU - G S Rowles AU - H B Bhat AU - R A Gillis Y1 - 1976/10/01 UR - http://jpet.aspetjournals.org/content/199/1/255.abstract N2 - Digitalis compounds are known to cause contraction of vascular smooth muscle. However, it has been reported by Kahn and colleagues (J. Pharmacol. Exp. Ther. 142: 215-222, 1963) that dihydro-ouabain has no effect on vascular tone in dogs. The purpose of our study was to reassess the vasoconstrictor activity of dihydro-ouabain. This was done by monitoring perfusion pressure of the canine hindlimb preparation perfused at a constant rate of blood flow and administering intra-arterial injections of dihydro-ouabain. Increasing doses of this drug (i.e., 25, 50, 100, 200 and 300 mug) produced significant dose-dependent increases in perfusion pressure. Pretreatment with phentolamine prevented the effect of dihydro-ouabain on perfusion pressure. These results indicate that dihydro-ouabain causes contraction of vascular smooth muscle by an adrenergic mechanism. ER -