Characterization of beta-adrenergic receptors in synaptic membranes from rat cerebral cortex and cerebellum

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:6520858

Lautens, L

Beta-adrenergic receptor ligand binding sites have been characterized in synaptic membranes from rat cerebral cortex and cerebellum using radioligand binding techniques. The equilibrium and kinetic properties of binding were assessed. The binding sites were non-interacting and exhibited two states of agonist binding which were sensitive to guanyl nucleotide. Synaptic membranes from cerebral cortex contained an equal number of beta/sub 1/- and beta/sub 2/-receptors; membranes from cerebellum possessed more beta/sub 2/-than beta/sub 1/-receptors. Photoaffinity labeling experiments revealed two different beta-adrenergic receptor polypeptides, R/sub 1/ and R/sub 2/ (and possibly a third, R/sub 3/) in synaptic membranes. The ratios of incorporation of photoaffinity label into R/sub 1/:/sub 2/ were approximately 1:1 (cerebral cortex) and 5:1 (cerebellum). Photoaffinity labeling of R/sub 1/ and R/sub 2/ was inhibited equally well by both agonist and antagonist in synaptic membranes from cerebellum; whereas agonist was a less potent inhibitor in membranes from cerebral cortex. Both subtypes of beta-adrenergic receptors exhibited the same apparent molecular weight in synaptic membranes from cerebral cortex. The beta-adrenergic receptors in synaptic membranes from cerebral cortex and cerebellum were glycoproteins which exhibited the same apparent molecular weight after exposure to endoglycosidase F. The partial proteolytic digest maps of photoaffinity labeled beta-adrenergic receptors from rat cerebral cortex, cerebellum, lung and heart were compared.

• Research Organization: Wisconsin Univ., Madison (USA)
• OSTI ID: 6520858
• Country of Publication: United States
• Language: English

Related Subjects

550601* -- Medicine-- Unsealed Radionuclides in Diagnostics
62 RADIOLOGY AND NUCLEAR MEDICINE
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BODY
BRAIN
CARBOHYDRATES
CELL CONSTITUENTS
CELL MEMBRANES
CENTRAL NERVOUS SYSTEM
CEREBELLUM
CEREBRUM
DRUGS
GLUCOPROTEINS
ISOTOPE APPLICATIONS
LABELLED COMPOUNDS
MAMMALS
MEMBRANE PROTEINS
MEMBRANES
MOLECULAR STRUCTURE
NERVOUS SYSTEM
ORGANIC COMPOUNDS
ORGANS
PROTEINS
RADIORECEPTOR ASSAY
RATS
RECEPTORS
RODENTS
SACCHARIDES
SYMPATHOMIMETICS
TRACER TECHNIQUES
VERTEBRATES