PT  - JOURNAL ARTICLE
AU  - FLEISCH, JEROME H.
AU  - TITUS, ELWOOD
TI  - EFFECT OF LOCAL ANESTHETICS ON PHARMACOLOGIC RECEPTOR SYSTEMS OF SMOOTH MUSCLE
DP  - 1973 Jul 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 44--51
VI  - 186
IP  - 1
4099  - http://jpet.aspetjournals.org/content/186/1/44.short
4100  - http://jpet.aspetjournals.org/content/186/1/44.full
SO  - J Pharmacol Exp Ther1973 Jul 01; 186
AB  - The effects of tetracaine and lidocaine on contractile responses of rat aorta to norepinephrine and KCl were measured and compared to the antagonism of norepinephrine and KCl by N-(2-chloroethyl)dibenzylamine hydrochloride (Dibenamine). Also, the effect of tetracaine on enrbamylcholine-induced contractions of rat trachea was investigated. Analysis of cumulative dose-response curves showed that the local anesthetics antagonized norepinephrine. carbamylcholine and KCl in a manner similar to that seen with Dibenamine. The initial parallel shift to the right of the norepinephrine and carbamycholine dose-response curves produced by the local anesthetics appeared to be caused by a change in the affinity constant of both the adrenergic and cholinergic receptors. The nonparallel shift in the dose-response curves seen with higher concentrations of the local anesthetics and the noncompetitive antagonism of the response to potassium were probably caused by the well-known effects of local anesthetics on the mobilization of Ca++ needed for smooth muscle contraction. © 1972 by The Williams & Wilkins Co.