PT  - JOURNAL ARTICLE
AU  - William C. Govier
AU  - Nancy C. Mosal
AU  - Peggy Whittington
AU  - Ann H. Broom
TI  - MYOCARDIAL <em>ALPHA</em> AND <em>BETA</em> ADRENERGIC RECEPTORS AS DEMONSTRATED BY ATRIAL FUNCTIONAL REFRACTORY-PERIOD CHANGES
DP  - 1966 Nov 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 255--263
VI  - 154
IP  - 2
4099  - http://jpet.aspetjournals.org/content/154/2/255.short
4100  - http://jpet.aspetjournals.org/content/154/2/255.full
SO  - J Pharmacol Exp Ther1966 Nov 01; 154
AB  - In an attempt to investigate the possibility that both alpha and beta adrenergic receptors are of importance in the myocardium, the response of the atrial functional refractory period to norepinephrine, epinephrine and isoproterenol has been analyzed by the use of phenoxybenzamine and pronethalol. It was found that the response consists of two opposing components, one tending to decrease the refractory period, the other increasing it. The order of potency of the three amines in producing the decrease is isoproterenol > epinephrine > norepinephrine. The decrease is also specifically blocked by pronethalol, and is, therefore, considered to be mediated through beta adrenergic receptors. The increase in refractory period is produced with the order of potency epinephrine > norepinephrine > isoproterenol, and is specifically blocked by phenoxybenzamine. The increase is, therefore, considered to be a function of alpha adrenergic receptors. It is concluded that both alpha and beta adrenergic receptors are present and have a function in the myocardium. © 1966 by The Williams & Wilkins Company