Alkaline phosphatase relieves desensitization of adenylate cyclase-coupled beta-adrenergic receptors in avian erythrocyte membranes

Conference · Fri May 01 04:00:00 EDT 1987 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:6120078

Stadel, J M; Rebar, R; Crooke, S T

Desensitization of adenylate cyclase-coupled ..beta..-adrenergic receptors in avian erythrocytes results in 40-65% decrease in agonist-stimulated adenylate cyclase activity and correlates with increased phosphorylation of ..beta..-adrenergic receptors. To assess the role of phosphorylation in desensitization, membranes from isoproterenol- and cAMP-desensitized turkey erythrocytes were incubated with alkaline phosphatase for 30 min at 37/sup 0/C, pH = 8.0. In both cases alkaline phosphatase treatment significantly reduced desensitization of agonist-stimulated adenylate cyclase activity by 40-60%. Similar results were obtained following alkaline phosphatase treatment of membranes from isoproterenol- and cAMP-desensitized duck erythrocytes. In addition, alkaline phosphatase treatment of membranes from duck erythrocytes desensitized with phorbol 12-mystrate 13-acetate returned adenylate cyclase activity to near control values. In all experiments inclusion of 20 mM NaPO/sub 4/ to inhibit alkaline phosphatase during treatment of membranes blocked the enzyme's effect on agonist-stimulated adenylate cyclase activity. These results demonstrate a role for phosphorylation in desensitization of adenylate cyclase-coupled ..beta..-adrenergic receptors in avian erythrocytes.

• Research Organization: SK and F Labs., Philadelphia, PA
• OSTI ID: 6120078
• Report Number(s): CONF-870644-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 46:6
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKALINE PHOSPHATASE
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BIOCHEMICAL REACTION KINETICS
BIOLOGICAL EFFECTS
BIOLOGICAL MATERIALS
BIRDS
BLOOD
BLOOD CELLS
BODY FLUIDS
CARCINOGENS
CELL CONSTITUENTS
CELL MEMBRANES
CHEMICAL REACTIONS
CYCLASES
DRUGS
ENZYME ACTIVITY
ENZYMES
ERYTHROCYTES
ESTERASES
ESTERS
HYDROLASES
INHIBITION
KINETICS
LYASES
MATERIALS
MEMBRANE PROTEINS
MEMBRANES
ORGANIC COMPOUNDS
PHORBOL ESTERS
PHOSPHATASES
PHOSPHORYLATION
PROTEINS
REACTION KINETICS
RECEPTORS
SYMPATHOMIMETICS
VERTEBRATES