A radioactively labeled alpha-adrenergic antagonist, [3H]dihydroergocryptine, binds specifically to a site on rabbit uterine membranes. Binding is rapid, reaching equilibrium in less than 17 minutes at 25 degrees C. Adrenergic agonists compete for this binding site with an order of affinities identical to the pharmacological potency order of these agents as alpha-adrenergic agonists (epinephrine greater than norepinephrine greater than isoprotereonl). The (-) stereoisomers of epinephrine and norepinephrine are 30 times more potent in competing for the site than the corresponding (+) stereoisomers. alpha-Adrenergic antagonists, such as phentolamine and phenoxybenzamine, potently compete for the binding sites while the beta-adrenergic antagonist propranolol does not. Structural analogs of catecholamines that are devoid of alpha-adrenergic physiological activity do not compete for [3H]dihydroergocryptine binding sites. These data suggest that alpha-adrenergic receptors can be directly identified and studied by [3H]dihydroergocryptine binding.
Determination of infundibular innervation and amine receptor content in cyanotic and acyanotic myocardium: relation to clinical events in tetralogy of Fallot
Identification and characterization of alpha 1-adrenergic receptors in human myometrium by [3H]prazosin binding
Parallel stimulation of ACTH, beta-LPH + beta-endorphin and alpha-MSH release by alpha-adrenergic agents in rat anterior pituitary cells in culture
N-Aralkyl substitution increases the affinity of adrenergic drugs for the alpha-adrenoceptor in rat liver
Thiol reactivity and the molecular individuality of alpha- and beta-adrenoreceptors in rat liver plasma membranes
Direct biochemical evidence for the existence of alpha-adrenergic receptors in hamster white adipocyte membranes
Myocardial adrenergic receptors and adenylate cyclase in the developing spontaneously hypertensive rat
Heterogeneity and subcellular localization of hamster adipocyte alpha-adrenergic receptors: evidence of alpha 1- and alpha 2-subtypes
Direct mapping of beta-adrenergic receptors in the rat central nervous system by a novel fluorescent beta-blocker
Adrenergic regulation of total systemic distensibility. Venous distensibility effects of norepinephrine and isoproterenol before and after selective adrenergic blockade
Synthesis of new haloperidol analogues and characterization of their interactions with alpha-adrenoceptors in rat parotid slices and human platelet membranes
Interactions of divalent cations and guanine nucleotides at alpha 2-noradrenergic receptor binding sites in bovine brain mechanisms
Characterization of postsynaptic alpha-adrenergic receptors by [3H]-dihydroergocryptine binding in muscular arteries from the rat mesentery
Adrenergic Receptors: Trafficking
Adrenergic receptor trafficking is an active physiological process where adrenergic receptors are relocated from one region of the cell to another or from one type of cell to another. Discover the latest research on adrenergic receptor trafficking here.