Characteristics of muscarinic receptors that selectively couple to inhibition of adenylate cyclase or stimulation of phospholipase C on NG108-15 and 1321N1 cells

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:7151953

Liang, M

The purpose of this dissertation was to establish whether different muscarinic receptor proteins selectively couple to different second messenger response system. Although both second messenger response systems are fully functional in both cell lines, activation of muscarinic cholinergic receptors only results in inhibition of adenylate cyclase in NG108-15 neuroblastoma {times} glioma cells and stimulation of phosphoinositide hydrolysis in 1321N1 human astrocytoma cells. Muscarinic receptors on both cell types were covalently labeled with ({sup 3}H)Propylbenzilylcholine mustard (({sup 3}H)PBCM) and the mobilities of the ({sup 3}H)PBCM-labelled species of both cells were compared by SDS-PAGE. 1321N1 and NG108-15 cells each primarily expressed a single ({sup 3}H)PBCM-labelled species with an apparent size of approximately 92,000 and 66,000 Da, respectively. ({sup 3}H)PBCM labelling was completely inhibited by 1 {mu}M atropine or by down-regulation of muscarinic receptors by an overnight incubation with carbachol. The apparent size of the ({sup 3}H)PBCM-labelled species of both cell lines was not altered by treatment with a series of protease inhibitors or by treatment with dithiothreitol and iodoacetamide. Another approach for determining differences in the muscarinic receptors of 2 cells lines was to study agonist-induced alteration of muscarinic receptor number. Exposure of both cell types to agonists resulted in rapid loss of muscarinic receptors from cell surface without change of total cellular muscarinic receptors followed by subsequently loss of receptors from cells. Muscarinic receptors on both cell lines were regulated by agonist with similar properties.

• Research Organization: North Carolina Univ., Chapel Hill, NC (USA). Inst. of Statistics
• OSTI ID: 7151953
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ANIMAL CELLS
BIOCHEMICAL REACTION KINETICS
DATA
DISEASES
ENZYME INHIBITORS
ENZYMES
EXPERIMENTAL DATA
GLIOMAS
HYDROGEN COMPOUNDS
HYDROLASES
INFORMATION
INHIBITION
ISOTOPE APPLICATIONS
KINETICS
LYASES
MEMBRANE PROTEINS
NEOPLASMS
NUMERICAL DATA
ORGANIC COMPOUNDS
PROTEINS
REACTION KINETICS
RECEPTORS
STIMULATION
TRACER TECHNIQUES
TRITIUM COMPOUNDS
TUMOR CELLS