Determination of the desensitization of beta-adrenergic receptors by [3H]CGP-12177

• Published in: Biochemical journal Vol. 216; no. 3; pp. 669 - 674
• Main Authors: Hertel, C, Müller, P, Portenier, M, Staehelin, M
• Format: Journal Article
• Language: English
• Published: England 15.12.1983
• Subjects: Adenylyl Cyclases - metabolism; Adrenergic beta-Antagonists - metabolism; Binding Sites; Binding, Competitive; Cell Line; Cell Membrane - metabolism; Centrifugation, Density Gradient; Dihydroalprenolol - metabolism; Glioma - metabolism; Humans; Isoproterenol - pharmacology; Propanolamines - metabolism; Receptors, Adrenergic, beta - drug effects
• ISSN: 0264-6021; 1470-8728
• DOI: 10.1042/bj2160669

Isoprenaline treatment of C6-glioma cells induced a fast decrease in the number of beta-adrenergic receptors as determined by binding of [3H]CGP-12177, which paralleled the decrease in the hormonally stimulated adenylate cyclase activity. The total number of receptors, as determined by binding of (-)-[3H]dihydroalprenolol, did not decrease. Separation of the beta-adrenergic receptors on a sucrose density gradient showed that the decrease in the number of receptors detectable with CGP-12177 was due to a movement of the receptors from the plasma membrane to a vesicular cell compartment. By using both (-)-[3H]dihydroalprenolol and [3H]CGP-12177 it is thus possible to differentiate between the total number of receptors and those present at the plasma membrane in an unfractionated cell lysate.