Preferential uncoupling by manganese of alpha adrenergic receptor mediated inhibition of adenylate cyclase in human platelets

Journal Article

Mn++ was found to preferentially uncouple the alpha receptor mediated inhibition of adenylate cyclase in human platelets under conditions where PGE1 stimulation of the enzyme was preserved. Since epinephrine competition curves with the antagonist radioligand [3H]yohimbine were unchanged by Mn++, it is likely that the Mn++ perturbs the interaction of an inhibitory regulatory component with adenylate cyclase rather than with the alpha receptor. The ability of low concentrations of Mn++ to selectively uncouple a functionally distinct pathway which mediates inhibition of adenylate cyclase by alpha-adrenergic agonists and guanine nucleotides should provide a useful tool for probing the mechanisms of hormonal regulation of the enzyme's activity. © 1981 Academic Press, Inc. All rights reserved.

Duke Authors

Cited Authors

  • Hoffman, BB; Yim, S; Tsai, BS; Lefkowitz, RJ

Published Date

  • 1981

Published In

Volume / Issue

  • 100 / 2

Start / End Page

  • 724 - 731

PubMed ID

  • 6268073

International Standard Serial Number (ISSN)

  • 0006-291X