Epinephrine-stimulated maintained rubidium efflux from guinea pig hepatocytes may involve alpha 1- and alpha 2-adrenoceptors

JM Henley

The epinephrine-stimulated maintained increase in 86Rb efflux from guinea pig hepatocytes may consist of both alpha 1- and alpha 2- adrenoceptor-mediated components. Both the alpha 1-selective adrenoceptor agonist phenylephrine and the alpha 2-selective agonist clonidine evoked a maintained increase in 86Rb efflux. Prazosin, an alpha 1-selective antagonist, did not inhibit the maintained increase in 86Rb efflux elicited by epinephrine, whereas yohimbine, an alpha 2- selective antagonist, did. In the absence of external Ca, no maintained increase in 86Rb efflux was observed. The results suggest that there may be two separate alpha-adrenergic sensitive Ca influx pathways into guinea pig hepatocytes, one mediated by alpha 1- and the other by alpha 2-adrenoceptor activation.

Volume 28, Issue 5, pp. 431-435, 11/01/1985
Copyright © 1985 by American Society for Pharmacology and Experimental Therapeutics