Alpha 2-adrenergic receptor stimulation of phospholipase A2 and of adenylate cyclase in transfected Chinese hamster ovary cells is mediated by different mechanisms
Journal Article
·
· Molecular Pharmacology; (USA)
OSTI ID:6057332
- Univ. of Missouri-Columbia (USA)
The effect of alpha 2-adrenergic receptor activation on adenylate cyclase activity in Chinese hamster ovary cells stably transfected with the alpha 2A-adrenergic receptor gene is biphasic. At lower concentrations of epinephrine forskolin-stimulated cyclic AMP production is inhibited, but at higher concentrations the inhibition is reversed. Both of these effects are blocked by the alpha 2 antagonist yohimbine but not by the alpha 1 antagonist prazosin. Pretreatment with pertussis toxin attenuates inhibition at lower concentrations of epinephrine and greatly potentiates forskolin-stimulated cyclic AMP production at higher concentrations of epinephrine. alpha 2-Adrenergic receptor stimulation also causes arachidonic acid mobilization, presumably via phospholipase A2. This effect is blocked by yohimbine, quinacrine, removal of extracellular Ca2+, and pretreatment with pertussis toxin. Quinacrine and removal of extracellular Ca2+, in contrast, have no effect on the enhanced forskolin-stimulated cyclic AMP production. Thus, it appears that the alpha 2-adrenergic receptor in these cells can simultaneously activate distinct signal transduction systems; inhibition of adenylate cyclase and stimulation of phospholipase A2, both via G1, and potentiation of cyclic AMP production by a different (pertussis toxin-insensitive) mechanism.
- OSTI ID:
- 6057332
- Journal Information:
- Molecular Pharmacology; (USA), Journal Name: Molecular Pharmacology; (USA) Vol. 39:2; ISSN MOPMA; ISSN 0026-895X
- Country of Publication:
- United States
- Language:
- English
Similar Records
cap alpha. /sub 2/-Adrenergic receptor-mediated sensitization of forskolin-stimulated cyclic AMP production
In vitro study of alpha 2-adrenoceptor turnover and metabolism using the adenocarcinoma cell line HT29
Alpha/sub 2/-adrenergic receptors on a platelet precursor cell line, HEL
Journal Article
·
Sat Feb 28 23:00:00 EST 1987
· Proc. Natl. Acad. Sci. U.S.A.; (United States)
·
OSTI ID:6125005
In vitro study of alpha 2-adrenoceptor turnover and metabolism using the adenocarcinoma cell line HT29
Journal Article
·
Sat Oct 31 23:00:00 EST 1987
· Mol. Pharmacol.; (United States)
·
OSTI ID:5652845
Alpha/sub 2/-adrenergic receptors on a platelet precursor cell line, HEL
Conference
·
Fri Feb 28 23:00:00 EST 1986
· Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)
·
OSTI ID:5451238
Related Subjects
550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMP
ANIMAL CELLS
ANTIGENS
AUTONOMIC NERVOUS SYSTEM AGENTS
BIOCHEMICAL REACTION KINETICS
CARBOXYLESTERASES
CHO CELLS
CYCLASES
DRUGS
ENZYME ACTIVITY
ENZYMES
ESTERASES
HYDROGEN COMPOUNDS
HYDROLASES
INHIBITION
ISOTOPE APPLICATIONS
KINETICS
LIPASES
LYASES
MATERIALS
MEMBRANE PROTEINS
NUCLEOTIDES
ORGANIC COMPOUNDS
PROTEINS
REACTION KINETICS
RECEPTORS
SYMPATHOMIMETICS
TOXIC MATERIALS
TOXINS
TRACER TECHNIQUES
TRITIUM COMPOUNDS
59 BASIC BIOLOGICAL SCIENCES
AMP
ANIMAL CELLS
ANTIGENS
AUTONOMIC NERVOUS SYSTEM AGENTS
BIOCHEMICAL REACTION KINETICS
CARBOXYLESTERASES
CHO CELLS
CYCLASES
DRUGS
ENZYME ACTIVITY
ENZYMES
ESTERASES
HYDROGEN COMPOUNDS
HYDROLASES
INHIBITION
ISOTOPE APPLICATIONS
KINETICS
LIPASES
LYASES
MATERIALS
MEMBRANE PROTEINS
NUCLEOTIDES
ORGANIC COMPOUNDS
PROTEINS
REACTION KINETICS
RECEPTORS
SYMPATHOMIMETICS
TOXIC MATERIALS
TOXINS
TRACER TECHNIQUES
TRITIUM COMPOUNDS