Abstract:
:When exposed to the beta-agonist (-)-isoproterenol, rat glioma C6 cells exhibited a time-and concentration-dependent reduction in isoproterenol responsiveness (desensitization) and a loss of beta-adrenergic receptors (down-regulation). Other agents, such as dibutyryl cyclic AMP, isobutylmethylxanthine, and cholera toxin, all of which elevate intracellular cyclic AMP levels, also induced receptor down-regulation but at a much slower rate than isoproterenol. Loss of beta-receptors was detected with intact cells, cell lysates, and cell membranes. Receptor loss was accompanied by a reduction in isoproterenol-stimulated cyclic AMP production and adenylate cyclase activity. For a given amount of receptor loss, this reduction was much greater with isoproterenol than with other agents. In addition, the concentration of isoproterenol required for half-maximal stimulation of cyclic AMP production was increased in cells treated with isoproterenol but not with isobutylmethylxanthine or dibutyryl cyclic AMP. The affinity of beta-receptors for the agonist was also lower in membranes from cells treated with isoproterenol but not the other agents. Prior treatment of the cells with cycloheximide inhibited receptor loss by isoproterenol but did not prevent desensitization or reduced affinity of beta-receptors for the agonist. Cycloheximide also blocked the loss of receptors induced by dibutyryl cyclic AMP and, in addition, prevented a reduction in agonist-stimulated adenylate cyclase activity. We propose that desensitization is mediated in rat glioma C6 cells only by agonists and is not dependent on either cyclic AMP or protein synthesis. Down-regulation can be induced both by agonists and by cyclic AMP and does depend on protein synthesis. Thus, desensitization and down-regulation can occur independently.
journal_name
Mol Pharmacoljournal_title
Molecular pharmacologyauthors
Zaremba TG,Fishman PHsubject
Has Abstractpub_date
1984-09-01 00:00:00pages
206-13issue
2eissn
0026-895Xissn
1521-0111journal_volume
26pub_type
杂志文章abstract::The neuropeptides vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase-activating peptide (PACAP) and their class II G protein-coupled receptors VPAC(1), VPAC(2), and PAC(1) play important roles in human physiology. No small molecule modulator has ever been reported for the VIP/PACAP receptors, and ther...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.109.060137
更新日期:2010-01-01 00:00:00
abstract::1-Deoxynojirimycin (DNM) is a saccharide decoy that inhibits cellular alpha-glucosidase I-II activity. Treatment by DNM of human immunodeficiency virus (HIV)-infected lymphocyte cultures inhibits virus spread. The functional properties of the membrane-associated Env glycoprotein (Env) modified in the presence of DNM r...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.61.1.186
更新日期:2002-01-01 00:00:00
abstract::An 'epoxygenase' eicosanoid analog, 14, 15-cis-episulfide-eicosatrienoic acid, has several unique pharmacological effects on platelets. These include (i) inhibition of ionophore A23187- but not thrombin-induced activation, (ii) inhibition of thromboxane B2 biosynthesis derived from endogenous but not exogenous arachid...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1991-02-01 00:00:00
abstract::Ro 11-2465 is a cyanide derivative of imipramine. In cerebral cortex homogenates, [3H] Ro 11-2465 displays a binding profile similar to that of [3H]imipramine. Agents compete with binding of [3H]Ro 11-2465 in an order of potency similar to their ability to block serotonin uptake, and raphe lesions greatly decrease the...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1983-05-01 00:00:00
abstract::An investigation of the conformational profiles of two cyclic delta-selective opioid peptides, [D-Pen2,D-Pen5]-enkephalin and [D-Pen2,L-Pen5]-enkephalin, has been made. The methods and procedures used are more extensive and systematic than those previously reported, involving a combination of nested grid rotations, cy...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1991-04-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.62.5.1076
更新日期:2002-11-01 00:00:00
abstract::The mouse adrenocortical Y-1 cell line has been found to express high affinity binding sites for neuropeptide Y (NPY). Pharmacological studies have shown that these NPY binding sites are of the Y1 type. Reverse transcription-polymerase chain reaction using primers specific for the rat Y1 receptor revealed that the NPY...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1995-07-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.113.089631
更新日期:2014-02-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1991-07-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1987-08-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1993-08-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.52.6.1095
更新日期:1997-12-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1986-09-01 00:00:00
abstract::Extracellular ATP activates two distinct types of P2 purinoreceptor-mediated signaling pathways in macrophages, 1) the rapid formation of nonselective pores/channels in the plasma membrane and 2) a guanine nucleotide-binding protein-dependent stimulation of phosphotidylinositol-specific phospholipase C, with subsequen...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1993-07-01 00:00:00
abstract::The 5-hydroxytryptamine3 receptor 5-HT3R has been implicated in gut and cardiac motility and in behavioral disorders. Characteristics of 5-HT3Rs appear to be heterogeneous among species, but human 5-HT3R cDNA has not been identified. We isolated a cDNA encoding 5-HT3R from human hippocampus. The mouse 5-HT3R gene has ...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1995-09-01 00:00:00
abstract::In isolated perfused rat livers, infusion of the sulfonylureas, glyburide (2.5 microM) and tolbutamide (0.5 mM), stimulated by 2-fold the rate of biliary glutathione secretion. This increase was mainly the result of an apparent increase in the rate of reduced glutathione release by the liver since oxidized glutathione...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1987-06-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/molpharm.120.000079
更新日期:2021-01-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1996-09-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1999-04-01 00:00:00
abstract::The metabotropic glutamate 5 receptor and the cannabinoid type 1 receptor are G protein-coupled receptors that are widely expressed in the central nervous system. Metabotropic glutamate 5 receptors, present at the postsynaptic site, are coupled to Gαq/11 proteins and display an excitatory response upon activation, whe...
journal_title:Molecular pharmacology
pub_type: 杂志文章,评审
doi:10.1124/mol.116.104372
更新日期:2016-11-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1986-10-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.104.005223
更新日期:2005-03-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.60.2.244
更新日期:2001-08-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.109.056838
更新日期:2009-10-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.108.045682
更新日期:2008-06-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1987-07-01 00:00:00
abstract::The molecular determinants of high-affinity human ether-a-go-go-related gene (HERG) potassium channel blockade by methanesulfonanilides include two aromatic residues (Phe656 and Tyr652) on the inner helices (S6) and residues on the pore helices that face into the inner cavity, but determinants for lower-affinity HERG ...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.104.001743
更新日期:2004-11-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.65.3.623
更新日期:2004-03-01 00:00:00
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journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.108.046169
更新日期:2008-07-01 00:00:00
abstract::The ability of four antidepressant drugs, imipramine, alaproclate, norzimelidine, and fluvoxamine, to inhibit serotonin transport into platelet plasma membrane vesicles was tested over a range of external Na+ concentrations. Imipramine affinity, as we previously reported [J. Biol. Chem. 258:6115-6119 (1983)] increases...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1988-06-01 00:00:00