PT - JOURNAL ARTICLE AU - Bevan, John A. AU - Osher, J. V. AU - Su, Che TI - RESPONSE OF VASCULAR SMOOTH MUSCLE TO POTASSIUM AND ITS ANTAGONISM BY PHENOXYBENZAMINE DP - 1963 Feb 01 TA - Journal of Pharmacology and Experimental Therapeutics PG - 216--221 VI - 139 IP - 2 4099 - http://jpet.aspetjournals.org/content/139/2/216.short 4100 - http://jpet.aspetjournals.org/content/139/2/216.full SO - J Pharmacol Exp Ther1963 Feb 01; 139 AB - The contractile response of the rabbit aorta strip following increase in the concentration of extracellular potassium is slower than that due to l-norepinephrine. It is reversible, is maintained indefinitely and the equilibrium response is unrelated to the rate of change of potassium concentration. The median effective concentration of potassium at 38°C is 23 ± S.E. 0.3 (n = 9) mEq/l. This response is antagonized by phenoxybenzamine in doses that have no effect on the contractile response to angiotensin or direct electrical stimulation. This specific potassium antagonism is also exhibited by SY-14 (N-(2-chloroethyl)- N - ethyl - 1 - naphthalenemethylamine hydrochloride) but not by yohimbine.