title: The resolution of agonist alpha 2-adrenergic receptor complexes from unoccupied receptors or antagonist-alpha 2 receptor complexes using DEAE chromatography.
abstract: Alpha 2-adrenergic receptors linked to inhibition of adenylate cyclase activity in human platelet membranes can be isolated using DEAE chromatography following solubilization into digitonin-containing buffers. This procedure permits resolution of agonist-occupied receptors from antagonist-occupied receptors. Antagonist-occupied receptors co-elute with unoccupied receptors. Adenylate cyclase activity elutes independently of all alpha 2-receptor activities. A greater resolution of agonist-receptor complexes from antagonist-receptor complexes is obtained using DEAE chromatography than reported earlier using approaches that rely entirely on agonist-stabilized increases in apparent receptor size. Consequently, DEAE chromatography may be of considerable value in isolating these agonist-receptor complexes to permit identification of the membrane component(s) which are more stably associated with the receptor subsequent to agonist occupancy and thus might be involved in receptor-cyclase coupling.
authors.forename: L E
authors.initials: LE
authors.lastname: Limbird
authors.forename: S T
authors.initials: ST
authors.lastname: MacMillan
authors.forename: D L
authors.initials: DL
authors.lastname: Kalinoski
mesh_terms: D000067956:Adenylyl Cyclase Inhibitors; D000316:Adrenergic alpha-Agonists / Q000302:isolation & purification* / Q000378:metabolism; D000317:Adrenergic alpha-Antagonists / Q000302:isolation & purification* / Q000378:metabolism; D001792:Blood Platelets / Q000378:metabolism; D002848:Chromatography, DEAE-Cellulose; D004074:Digitoxin / Q000494:pharmacology; D006801:Humans; D011942:Receptors, Adrenergic, alpha / Q000302:isolation & purification* / Q000378:metabolism; D012995:Solubility
chemical_list: D000067956:Adenylyl Cyclase Inhibitors; D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D011942:Receptors, Adrenergic, alpha; D004074:Digitoxin