Agonist-induced alterations in lymphocyte. beta. -adrenergic receptor photoaffintiy labelling: effects of phenylarsine oxide

Conference · Sat Mar 01 04:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:5454185

Feldman, R D; McArdle, W; Lai, C

In several models, desensitization of the ..beta..-adrenergic receptor (..beta..AR) is associated with a decrease in binding of hydrophilic but not hydrophobic ..beta..AR ligands. This suggests a sequestration of cell surface ..beta..AR. Desensitization of the lymphobyte ..beta..AR is also associated with a selective reduction in the photoaffinity labelling of a 55K ..beta..AR protein as compared to a 68K ..beta..AR protein. In order to examine the relationship between sequestration and reduction in labelling of the 55K peptide, the authors have studied the effect of phenylarsine oxide (PAO; an inhibitor of sequestration) on lymphocyte ..beta..AR desensitization. Incubation of cells with PAO prior to desensitization did not block the consequent reduction in isoproterenol-stimulated adenylate cyclase activity. However, the agonist-induced reduction in binding of the hydrophilic ..beta..AR ligand CGP-12177 was blocked by PAO (without PAO:57 +/- 4% of control, with PAO: 97 +/- 2% of control). Photolabelling studies with (/sup 125/I) iodocyanopindolol diazirine revealed that PAO pretreatment also blocked the selective loss in labelling of the 55K ..beta..AR protein seen with desensitization. These data suggest that loss of labelling of the 55K protein of the ..beta..AR is closely coupled to ..beta..AR sequestration.

• Research Organization: Univ. of Iowa, Iowa City
• OSTI ID: 5454185
• Report Number(s): CONF-8604222-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 45:3
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AFFINITY
ANIMAL CELLS
AUTONOMIC NERVOUS SYSTEM AGENTS
BIOLOGICAL MATERIALS
BLOOD
BLOOD CELLS
BODY FLUIDS
CONNECTIVE TISSUE CELLS
DRUGS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
LABELLING
LEUKOCYTES
LYMPHOCYTES
MATERIALS
MEMBRANE PROTEINS
ORGANIC COMPOUNDS
PROTEINS
RECEPTORS
SOMATIC CELLS
SYMPATHOMIMETICS
TRACER TECHNIQUES
TRITIUM COMPOUNDS