The binding characteristics and number of beta-adrenergic receptors on the turkey erythrocyte

Proc Natl Acad Sci U S A. 1974 Jul;71(7):2773-6. doi: 10.1073/pnas.71.7.2773.

Abstract

Turkey erythrocyte ghosts (empty membranes) possess a class of receptors that can bind both L-[(3)H]isoproterenol and DL-[(3)H]propranolol. The binding of [(3)H]isoproterenol to these receptors occurs with a dissociation constant of 0.15 muM and can be fully inhibited by 1 muM propranolol. The binding of [(3)H]propranolol occurs with a dissociation constant of 2.5 nM and can be fully inhibited by 0.2 mM DL-isoproterenol. Ligand binding is sensitive to sonication, boiling, and 8 M urea. The cells possess 500 to 1000 beta-adrenergic receptors per cell. Binding of propranolol to the beta-receptor was found to be stereospecific for the L stereoisomer. If one assumed a 1:1 relationship between beta-adrenergic receptors and adenylate cyclase, the turnover number of this adenylate cyclase would be close to 100 min(-1).

MeSH terms

  • Adenylyl Cyclases / biosynthesis
  • Animals
  • Binding, Competitive
  • Cell Membrane / metabolism
  • Epinephrine / metabolism
  • Erythrocytes / enzymology
  • Erythrocytes / metabolism*
  • Hot Temperature
  • Isoproterenol / metabolism
  • Ligands
  • Propranolol / metabolism
  • Protein Binding
  • Receptors, Adrenergic*
  • Tritium
  • Turkeys / metabolism*
  • Ultracentrifugation
  • Urea / pharmacology

Substances

  • Ligands
  • Receptors, Adrenergic
  • Tritium
  • Urea
  • Propranolol
  • Adenylyl Cyclases
  • Isoproterenol
  • Epinephrine