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Title: Receptor-mediated inhibition of adenylate cyclase and stimulation of arachidonic acid release in 3T3 fibroblasts. Selective susceptibility to islet-activating protein, pertussis toxin

Thrombin exhibited diverse effects on mouse 3T3 fibroblasts. It (a) decreased cAMP in the cell suspension, (b) inhibited adenylate cyclase in the Lubrol-permeabilized cell suspension in a GTP-dependent manner, increased releases of (c) arachidonic acid and (d) inositol from the cell monolayer prelabeled with these labeled compounds, (e) increased /sup 45/Ca/sup 2 +/ uptake into the cell monolayer, and (f) increased /sup 86/Rb/sup +/ uptake into the cell monolayer in a ouabain-sensitive manner. Most of the effects were reproduced by bradykinin, platelet-activating factor, and angiotensin II. The receptors for these agonists are thus likely to be linked to three separate effector systems: the adenylate cyclase inhibition, the phosphoinositide breakdown leading to Ca/sup 2 +/ mobilization and phospholipase A2 activation, and the Na,K-ATPase activation. Among the effects of these agonists, (a), (b), (c), and (e) were abolished, but (d) and (f) were not, by prior treatment of the cells with islet-activating protein (IAP), pertussis toxin, which ADP-ribosylates the Mr = 41,000 protein, the alpha-subunit of the inhibitory guanine nucleotide regulatory protein (Ni), thereby abolishing receptor-mediated inhibition of adenylate cyclase. The effects (a), (c), (d), and (e) of thrombin, but not (b), were mimicked by A23187, a calcium ionophore. The effects ofmore » A23187, in contrast to those of receptor agonists, were not affected by the treatment of cells with IAP. Thus, the IAP substrate, the alpha-subunit of Ni, or the protein alike, may play an additional role in signal transduction arising from the Ca/sup 2 +/-mobilizing receptors, probably mediating process(es) distal to phosphoinositide breakdown and proximal to Ca/sup 2 +/ gating.« less
Authors:
;
Publication Date:
OSTI Identifier:
6528979
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Biol. Chem.; (United States); Journal Volume: 12
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; ATP-ASE; ENZYME ACTIVITY; CYCLASES; FIBROBLASTS; SENSITIVITY; RECEPTORS; BIOCHEMICAL REACTION KINETICS; THROMBIN; BIOLOGICAL EFFECTS; ANGIOTENSIN; ARACHIDONIC ACID; BACTERIA; BLOOD COAGULATION FACTORS; BRADYKININ; CALCIUM 45; CATIONS; CELL MEMBRANES; CHLORIDES; INOSITOL; MICE; RUBIDIUM 86; TOXINS; TRACER TECHNIQUES; TRITIUM; ACID ANHYDRASES; ALKALI METAL ISOTOPES; ALKALINE EARTH ISOTOPES; ANIMAL CELLS; ANIMALS; ANTIGENS; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; CALCIUM ISOTOPES; CARBOHYDRATES; CARBOXYLIC ACIDS; CARDIOVASCULAR AGENTS; CELL CONSTITUENTS; CHARGED PARTICLES; CHLORINE COMPOUNDS; COAGULANTS; CONNECTIVE TISSUE CELLS; DAYS LIVING RADIOISOTOPES; DRUGS; ENZYMES; EVEN-ODD NUCLEI; GLOBULINS; HALIDES; HALOGEN COMPOUNDS; HEMATOLOGIC AGENTS; HEMOSTATICS; HYDROGEN ISOTOPES; HYDROLASES; INOSITOLS; INTERMEDIATE MASS NUCLEI; IONS; ISOMERIC TRANSITION ISOTOPES; ISOTOPE APPLICATIONS; ISOTOPES; KINETICS; KININS; LIGHT NUCLEI; LYASES; MAMMALS; MATERIALS; MEMBRANES; MICROORGANISMS; MINUTES LIVING RADIOISOTOPES; MONOCARBOXYLIC ACIDS; MONOSACCHARIDES; NUCLEI; ODD-EVEN NUCLEI; ODD-ODD NUCLEI; ORGANIC ACIDS; ORGANIC COMPOUNDS; PEPTIDE HYDROLASES; PEPTIDES; PHOSPHOHYDROLASES; POLYPEPTIDES; PROTEINS; RADIOISOTOPES; REACTION KINETICS; RODENTS; RUBIDIUM ISOTOPES; SACCHARIDES; SERINE PROTEINASES; SOMATIC CELLS; TOXIC MATERIALS; VASOCONSTRICTORS; VERTEBRATES; YEARS LIVING RADIOISOTOPES 550201* -- Biochemistry-- Tracer Techniques