Abstract:
:Four piperazinoquinolone antibacterial drugs (norfloxacin, ciprofloxacin, enoxacin, and pipemidic acid), known to be gamma-aminobutyric acid (GABA) antagonists, fully reversed the inhibitory effect of GABA on [35S]t-butylbicyclophosphorothionate ([35S] TBPS) binding to rat brain membranes in vitro. Twelve indomethacin/ibuprofen-like arylalkanoic acid (AAA) anti-inflammatory drugs alone had no effect on [35S]TBPS binding, or on its inhibition by GABA, but potentiated the GABA-antagonistic effects of the four quinolones. Felbinac (4-biphenylacetic acid) was most potent in this respect (EC50 = 110 nM, together with 5 microM norfloxacin), followed by flurbiprofen > anirolac > metiazinic acid > tolmetin = ketoprofen = fenbufen = indomethacin > fenoprofen > ibuprofen = (+)-naproxen = sulindac. Other anti-inflammatory analgesic drugs, including aspirin, diclofenac, diflunisal, meclofenamic acid, mefenamic acid, nambumetone, phenacetin, piroxicam, and phenylbutazone, failed to potentiate the GABA-antagonistic effect of norfloxacin. Felbinac (1 microM) increased the GABA-antagonistic potencies of norfloxacin and enoxacin about 26-fold, while increasing those of ciprofloxacin and pipemidic acid 7-fold and 2.3-fold, respectively. Using subsaturating concentrations of the four quinolones, concentration-response curves for felbinac yielded EC50 values ranging from 110 nM with 5 microM norfloxacin to 1.3 microM with 100 microM pipemidic acid. Three other piperazinoquinolone antibacterial agents (amifloxacin, difloxacin, and fleroxacin) and four nonpiperazinoquinolone anti-bacterial agents (oxolinic acid, cinoxacin, nalidixic acid, and piromidic acid) were much weaker GABA antagonists and were not significantly potentiated by felbinac. All other known GABAA receptor blockers tested, including R 5135, pitrazepin, bicuculline, SR 95531, strychnine, D-tubocurarine, thebaine, securinine, theophylline, and caffeine, were not potentiated by felbinac. Our results suggest that norfloxacin and related piperazinoquinolones, acting at GABAA receptors, may induce a high affinity binding site for indomethacin/ibuprofen-like anti-inflammatory agents (the AAA site) that, when occupied, reciprocally increases the affinities of the quinolones for GABAA receptors. The AAA binding site may be a new site in the GABAA receptor complex.
journal_name
Mol Pharmacoljournal_title
Molecular pharmacologyauthors
Squires RF,Saederup Esubject
Has Abstractpub_date
1993-05-01 00:00:00pages
795-800issue
5eissn
0026-895Xissn
1521-0111journal_volume
43pub_type
杂志文章abstract::The N-methyl-D-aspartate (NMDA)-sensitive glutamate receptors are known to be inhibited by 3-amino-1-hydroxy-2-pyrrolidone (HA-966) and 7-chlorokynurenic acid (Cl-KYN), which act at the glycine-regulated allosteric modulatory center. In this work we show that, in synaptic membranes prepared from rat brain, Cl-KYN and ...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1989-12-01 00:00:00
abstract::Vitamin A-derived metabolites act as ligands for nuclear receptors controlling the expression of a number of genes. Stereospecific saturation of the C(13)-C(14) double bond of all-trans-retinol by the enzyme, retinol saturase (RetSat), leads to the production of (R)-all-trans-13,14-dihydroretinol. In liver and adipose...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.109.060038
更新日期:2009-12-01 00:00:00
abstract::The diphosphoinositol polyphosphates ("inositol pyrophosphates") are a specialized subgroup of the inositol phosphate signaling family. This review proposes that many of the current data concerning the metabolic turnover and biological effects of the diphosphoinositol polyphosphates are linked by a common theme: these...
journal_title:Molecular pharmacology
pub_type: 杂志文章,评审
doi:10.1124/mol.109.055897
更新日期:2009-08-01 00:00:00
abstract::The role of the cGMP-dependent protein kinase (cGK) and one of its major substrates, the vasodilator-stimulated phosphoprotein (VASP), in the regulation of a receptor-evoked calcium response was investigated. The human type I beta cGK was stably transfected in human embryonic kidney 293 cells and Swiss mouse 3T6 fibro...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1994-08-01 00:00:00
abstract::The binding of two anthranilic acid derivatives, glafenic and floctafenic acids, to human erythrocytes and plasma proteins has been investigated in vitro by equilibrium dialysis. Despite their close chemical structures it was shown that the binding of the two compounds to serum albumin, lipoproteins, and erythrocytes ...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1987-03-01 00:00:00
abstract::The lymphocyte potassium channel Kv1.3 is widely regarded as a promising new target for immunosuppression. To identify a potent small-molecule Kv1.3 blocker, we synthesized a series of 5-phenylalkoxypsoralens and tested them by whole-cell patch clamp. The most potent compound of this series, 5-(4-phenylbutoxy)psoralen...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.65.6.1364
更新日期:2004-06-01 00:00:00
abstract::The anti-arrhythmic quinidine has been reported to be a competitive inhibitor of the catalytic activities of human liver P-450DB, including sparteine delta 2-oxidation and bufuralol 1'-hydroxylation, and we confirmed the observation that submicromolar concentrations are strongly inhibitory. Human liver microsomes oxid...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1986-09-01 00:00:00
abstract::Previous studies have shown that at least two subtypes of somatostatin (SRIF) receptors (SRIF1 and SRIF2) are expressed in mammalian cells. SRIF1 receptors have high affinity for MK 678, whereas SRIF2 receptors have no affinity for MK 678 but selectively bind peptides with structures similar to that of CGP 23996. Rece...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1992-07-01 00:00:00
abstract::A quantum chemical study of adenosine, formycin, and their 2-NH2 and 2-F derivatives is performed. The tautomerism of neutral and protonated species as well as the protonation of adenosine, formycin, and their derivatives are theoretically studied using semiempirical MNDO and AM1, as well as ab initio STO-3G methods. ...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1989-02-01 00:00:00
abstract::Maurotoxin (MTX) is a potent blocker of human voltage-activated Kv1.2 and intermediate-conductance calcium-activated potassium channels, hIKCa1. Because its blocking affinity on both channels is similar, although the pore region of these channels show only few conserved amino acids, we aimed to characterize the bindin...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.104.002774
更新日期:2004-11-01 00:00:00
abstract::Microglia, as phagocytes and antigen-presenting cells in the central nervous system, are activated in such disease processes as stroke and multiple sclerosis. Because peripheral macrophages are capable of producing endocannabinoids, we have examined endocannabinoid production in a macrophage-colony stimulating factor ...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.65.4.999
更新日期:2004-04-01 00:00:00
abstract::Potassium channels play fundamental roles in physiology. Chemically diverse drugs bind in the pore region of K+ channels. Here, we homology-modeled voltage- and Ca2+-gated K+ channel BK and voltage-gated Kv1.3 using the X-ray structures of MthK and Kv1.2, respectively, and simulated the binding of d-tubocurarine in th...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.105.017970
更新日期:2006-04-01 00:00:00
abstract::Neuronal cell degeneration was studied in vitro in primary rat brain neuronal cultures grown in serum-free, chemically defined, CDM R12 medium, by measuring lactate dehydrogenase (LDH) released in the culture medium. A Ca2+-dependent neuronal cell degeneration was observed after prolonged and transient exposure 30 mic...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1989-10-01 00:00:00
abstract::Ovarian cancer is the leading cause of death from gynecological malignancy and has the worst prognosis of all gynecological cancers. Vascular endothelial growth factor (VEGF) plays an important role in ovarian cancer development. 9-beta-D-Arabinofuranosyl-2-fluoroadenine (Fara-A), a nucleotide analog, is frequently us...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.66.1.178
更新日期:2004-07-01 00:00:00
abstract::Metabolism of the pulmonary toxin, 4-ipomeanol, in microsomal preparations from rabbit liver and lung and in purified cytochrome P-450-dependent monooxygenase systems was investigated. The rate of formation of reactive electrophilic products from 4-ipomeanol was estimated by measuring covalent binding to protein or gl...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1982-11-01 00:00:00
abstract::The aim of this study was to use pharmacological inhibition of protein kinase A and mutation of potential protein kinase A phosphorylation sites to determine the role of protein kinase A-catalyzed phosphorylation of the dopamine D(1) receptor in agonist-stimulated desensitization and internalization of the receptor. T...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.61.4.806
更新日期:2002-04-01 00:00:00
abstract::The nuclear pregnane X receptor (PXR) and constitutive androstane receptor (CAR) play central roles in protecting the body against environmental chemicals (xenobiotics). PXR and CAR are activated by a wide range of xenobiotics and regulate cytochrome P450 and other genes whose products are involved in the detoxificati...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.62.3.638
更新日期:2002-09-01 00:00:00
abstract::The human mu-opioid receptor (HmuOR) is a G-protein coupled receptor that mediates analgesia, euphoria and other important central and peripheral neurological functions. In this study, we found in a yeast two-hybrid screen that a protein kinase C-interacting protein (PKCI) specifically interacts with the C terminus of...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.66.5.
更新日期:2004-11-01 00:00:00
abstract::We searched for sites on the alpha-subunit of the fast Na(+) channel responsible for the difference in GTX (grayanotoxin) sensitivity of the skeletal- and cardiac-muscle Na(+) current. cDNA clones, encoding the skeletal or cardiac isoforms of the alpha-subunit, were inserted into a mammalian expression vector and tran...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:2001-10-01 00:00:00
abstract::Three different cDNA clones, namely DM1-1, Dah1, and Dah2, encoding hepatic cytochrome P-450, were isolated from a cDNA library in lambda gt11 constructed from liver RNA of polychlorinated biphenyl-treated beagle dogs. DM1-1 was 1857 base pairs (bp) long and encoded a polypeptide of 457 residues. Dah1 was 2394 bp long...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1990-11-01 00:00:00
abstract::A collection of analogues of atrial natriuretic peptide (ANP) were screened for their ability to inhibit ANP-induced cGMP stimulation. The antagonists revealed through this screen are structurally related; almost all are substituted at either aspartate-13 or phenylalanine-26. This tendency is consistent throughout sev...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1990-12-01 00:00:00
abstract::Unlike the majority of G protein-coupled receptors, the prostaglandin E(2) (PGE(2)) E-prostanoid 3 (EP3) receptor binds agonist with high affinity that is insensitive to the presence of guanosine 5[prime]-O-(3-thio)triphosphate (GTPγS). We report the identification of mutations that confer GTPγS sensitivity to agonist...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.112.080473
更新日期:2013-01-01 00:00:00
abstract::Binding by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) to the Ah receptor leads to transcriptional activation of several genes and a toxicity syndrome that includes tumor promotion, wasting, hormonal and immune system dysfunction, and death. Recent findings indicate that TCDD may also affect cardiac function. Here, we ...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:
更新日期:1993-12-01 00:00:00
abstract::In this work, we evaluate the structural differences of transmembrane helix 3 in rhodopsin and the 5-hydroxytryptamine 1A (5-HT1A) receptor caused by their different amino acid sequence. Molecular dynamics simulations of helix 3 in the 5-HT1A receptor tends to bend toward helix 5, in sharp contrast to helix 3 in rhodo...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.62.1.15
更新日期:2002-07-01 00:00:00
abstract::Anandamide (AEA) and delta9-tetrahydrocannabinol (THC) are endogenous and exogenous ligands, respectively, for cannabinoid receptors. Whereas most of the pharmacological actions of cannabinoids are mediated by CB1 receptors, there is also evidence that these compounds can produce effects that are not mediated by the a...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.105.019174
更新日期:2006-03-01 00:00:00
abstract::Combining chemotherapeutics to treat malignant tumors has been shown to be effective in preventing drug resistance, tumor recurrence, and reducing tumor size. We modeled combination drug therapy in PC-3 human prostate cancer cells using mixture design response surface methodology (MDRSM), a statistical technique desig...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.117.111450
更新日期:2018-08-01 00:00:00
abstract::Dysregulation of the chemokine system is implicated in a number of autoimmune and inflammatory diseases, as well as cancer. Modulation of chemokine receptor function is a very promising approach for therapeutic intervention. Despite interest from academic groups and pharmaceutical companies, there are currently few ap...
journal_title:Molecular pharmacology
pub_type: 杂志文章,评审
doi:10.1124/mol.119.116954
更新日期:2019-12-01 00:00:00
abstract::Identifying novel mechanisms to enhance glucagon-like peptide-1 (GLP-1) receptor signaling may enable nascent medicinal chemistry strategies with the aim of developing new orally available therapeutic agents for the treatment of type 2 diabetes mellitus. Therefore, we tested the hypothesis that selectively modulating ...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.112.080432
更新日期:2012-12-01 00:00:00
abstract::Regulator of G protein signaling (RGS) proteins accelerate the endogenous GTPase activity of Galpha(i/o) proteins to increase the rate of deactivation of active Galpha-GTP and Gbetagamma signaling molecules. Previous studies have suggested that RGS proteins are more effective on less efficiently coupled systems such a...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.107.043547
更新日期:2008-05-01 00:00:00
abstract::Neuromedin U (NmU) is a 25 amino acid peptide prominently expressed in the upper gastrointestinal (GI) tract and central nervous system. It is highly conserved throughout evolution and induces smooth muscle contraction in a variety of species. Our understanding of NmU biology has been limited because the identity of i...
journal_title:Molecular pharmacology
pub_type: 杂志文章
doi:10.1124/mol.58.4.870
更新日期:2000-10-01 00:00:00