101
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Affiliation(s)
- Patrizio Blandina
- Dipartimento di Farmacologia Preclinica e Clinica, Università di Firenze, Italy.
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102
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Nowak P, Dabrowska J, Bortel A, Biedka I, Szczerbak G, Słomian G, Kostrzewa RM, Brus R. Histamine H3 receptor agonist- and antagonist-evoked vacuous chewing movements in 6-OHDA-lesioned rats occurs in an absence of change in microdialysate dopamine levels. Eur J Pharmacol 2006; 552:46-54. [PMID: 17055481 DOI: 10.1016/j.ejphar.2006.08.092] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2006] [Revised: 07/20/2006] [Accepted: 08/04/2006] [Indexed: 10/24/2022]
Abstract
In rats lesioned neonatally with 6-hydroxydopamine (6-OHDA), repeated treatment with SKF 38393 (1-phenyl-2,3,4,5-tetrahydro-(1H)-3-benzazepine-7,8-diol), a dopamine D(1)/D(5) receptor agonist, produces robust stereotyped and locomotor activities. The gradual induction of dopamine D(1) receptor supersensitivity is known as a priming phenomenon, and this process is thought to underlie not only the appearance of vacuous chewing movements in humans with tardive dyskinesia, but also the onset of motor dyskinesias in L-dihydroxyphenylalanine (L-DOPA)-treated Parkinson's disease patients. The object of the present study was to determine the possible influence of the histaminergic system on dopamine D(1) agonist-induced activities. We found that neither imetit (5.0 mg/kg i.p.), a histamine H(3) receptor agonist, nor thioperamide (5.0 mg/kg i.p.), a histamine H(3) receptor antagonist/inverse agonist, altered the numbers of vacuous chewing movements in non-primed-lesioned rats. However, in dopamine D(1) agonist-primed rats, thioperamide alone produced a vacuous chewing movements response (i.e., P < 0.05 vs SKF 38393, 1.0 mg/kg i.p.), but did not modify the SKF 38393 effect. Notably, both imetit and thioperamide-induced catalepsy in both non-primed and primed 6-OHDA-lesioned rats, comparable in magnitude to the effect of the dopamine D(1)/D(5) receptor antagonist SCH 23390 (7-chloro-8-hydroxy-3-methyl-1-phenyl-2,3,4,5-tetrahydro-1H-3-benzazepine; 0.5 mg/kg i.p.). Furthermore, in primed animals both imetit and thioperamide intensified SCH 23390-evoked catalepsy. In vivo microdialysis established that neither imetit nor thioperamide altered extraneuronal levels of dopamine and its metabolites in the striatum of 6-OHDA-lesioned rats. On the basis of the present study, we believe that histaminergic systems may augment dyskinesias induced by dopamine receptor agonists, independent of direct actions on dopaminergic neurons.
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Affiliation(s)
- Przemysław Nowak
- Department of Pharmacology, Medical University of Silesia, H. Jordana 38, 41-808 Zabrze, Poland.
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103
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Celanire S, Wijtmans M, Talaga P, Leurs R, de Esch IJP. Keynote review: histamine H3 receptor antagonists reach out for the clinic. Drug Discov Today 2006; 10:1613-27. [PMID: 16376822 DOI: 10.1016/s1359-6446(05)03625-1] [Citation(s) in RCA: 180] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Antagonists of the histamine H(1) and H(2) receptors have been successful as blockbuster drugs for treating allergic conditions and gastric ulcers, respectively. As such, histamine receptors have made a significant contribution to establishing G-Protein-coupled receptors as the favored drug targets of the industry. In this light, it can easily be understood that the discovery of a third histamine receptor subtype (H(3)R) in 1983 was greeted with considerable excitement. However, characterization of the H(3)R turned out to be far from trivial. In the past five years, molecular biology approaches have given fresh impetus to the H(3)R research field. As a result, H(3)R ligands are where they were anticipated to be 20 years ago: at the center of attention and on the verge of an anticipated breakthrough as the next generation of histaminergic blockbuster drugs. Here, we assess the status of the H(3)R medicinal chemistry programs of the various players in the field, as far as can be deduced from patent applications and scientific literature.
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Affiliation(s)
- Sylvain Celanire
- Department of Chemical Research, Chemin du Foriest, B-1420 Braine-l'Alleud, Belgium
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104
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Pan JB, Yao BB, Miller TR, Kroeger PE, Bennani YL, Komater VA, Esbenshade TA, Hancock AA, Decker MW, Fox GB. Evidence for tolerance following repeated dosing in rats with ciproxifan, but not with A-304121. Life Sci 2006; 79:1366-79. [PMID: 16730751 DOI: 10.1016/j.lfs.2006.04.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2005] [Revised: 01/31/2006] [Accepted: 04/04/2006] [Indexed: 11/17/2022]
Abstract
Blockade of presynaptic histamine H(3) receptors with potent and selective ligands improves cognitive function in rodents and there is significant interest in developing such drugs for long-term symptomatic treatment of CNS disorders such as attention deficit hyperactivity disorder (ADHD). Unfortunately, little is known about the effects of repeated exposure to H(3) receptor antagonists/inverse agonists. We therefore investigated the effects of acute and repeated daily administration of two potent, brain penetrating H(3) receptor antagonists/inverse agonists, ciproxifan and A-304121, on rat body weight, food and water intake, core temperature and locomotor activity, as well as H(3) receptor density and gene expression levels. Methylphenidate, used clinically for the treatment of ADHD, was included as an additional comparator. Ciproxifan, an imidazole-based compound, decreased food intake over the first 10 days and locomotor activity acutely, but these effects were lost after further repeated administration. The ex vivo binding studies revealed increased H(3) receptor density in rats following repeated administration of ciproxifan for 10 or 15 days; however, H(3) receptor gene expression was not changed. In contrast, rats treated with the non-imidazole, A-304121, did not differ from controls on any measure during the observation period, while rats treated with methylphenidate exhibited hyperthermia and hyperactivity. The implications for potential long-term treatment with H(3) receptor antagonists in CNS disorders such as ADHD are discussed.
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Affiliation(s)
- Jia Bao Pan
- Neuroscience Research, Abbott Laboratories, 100 Abbott Road, Abbott Park, IL 60064-6125, USA.
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105
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Jesudason CD, Beavers LS, Cramer JW, Dill J, Finley DR, Lindsley CW, Stevens FC, Gadski RA, Oldham SW, Pickard RT, Siedem CS, Sindelar DK, Singh A, Watson BM, Hipskind PA. Synthesis and SAR of novel histamine H3 receptor antagonists. Bioorg Med Chem Lett 2006; 16:3415-8. [PMID: 16677814 DOI: 10.1016/j.bmcl.2006.04.004] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2006] [Revised: 03/31/2006] [Accepted: 04/03/2006] [Indexed: 11/28/2022]
Abstract
The synthesis and biological evaluation of novel tetrahydroisoquinoline, tetrahydroquinoline, and tetrahydroazepine antagonists of the human and rat H(3) receptors are described. The substitution around these rings as well as the nature of the substituent on nitrogen is explored. Several compounds with high affinity and selectivity for the human and rat H(3) receptors are reported.
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Affiliation(s)
- Cynthia D Jesudason
- Lilly Research Laboratories, Eli Lilly & Company, Lilly Corporate Center, Indianapolis, IN 46285, USA.
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106
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Łazewska D, Ligneau X, Schwartz JC, Schunack W, Stark H, Kieć-Kononowicz K. Ether derivatives of 3-piperidinopropan-1-ol as non-imidazole histamine H3 receptor antagonists. Bioorg Med Chem 2006; 14:3522-9. [PMID: 16466921 DOI: 10.1016/j.bmc.2006.01.013] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2005] [Revised: 12/29/2005] [Accepted: 01/06/2006] [Indexed: 11/16/2022]
Abstract
A series of aliphatic and aromatic ether derivatives of 3-piperidinopropan-1-ol has been prepared by four different methods. The ethers obtained were evaluated for their affinities at recombinant human histamine H3 receptor, stably expressed in CHO-K1 or HEK 293 cells. All compounds investigated show from moderate to high in vitro affinities in the nanomolar concentration range. Selected compounds were investigated under in vivo conditions after oral administration to mice. Some proved to be highly potent and orally available histamine H3 receptor antagonists. The most potent antagonists in this series have been in vitro the 4-(1,1-dimethylpropyl)phenyl ether 19 (hH3R K(i) = 8.4 nM) and in vivo the simple ethyl ether 2 (ED50 = 1.0mg/kg).
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Affiliation(s)
- Dorota Łazewska
- Jagiellonian University Medical College, Faculty of Pharmacy, Department of Technology and Biotechnology of Drugs, Medyczna 9, 30-688 Kraków, Poland
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107
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Letavic MA, Barbier AJ, Dvorak CA, Carruthers NI. Recent medicinal chemistry of the histamine H3 receptor. PROGRESS IN MEDICINAL CHEMISTRY 2006; 44:181-206. [PMID: 16697898 DOI: 10.1016/s0079-6468(05)44405-7] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Affiliation(s)
- Michael A Letavic
- Johnson and Johnson Pharmaceutical Research and Development LLC, San Diego, CA 92121, USA
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108
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Ito S, Yoshimoto R, Miyamoto Y, Mitobe Y, Nakamura T, Ishihara A, MacNeil DJ, Kanatani A, Tokita S. Detailed pharmacological characterization of GT-2331 for the rat histamine H3 receptor. Eur J Pharmacol 2006; 529:40-6. [PMID: 16316645 DOI: 10.1016/j.ejphar.2005.10.066] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Revised: 10/21/2005] [Accepted: 10/26/2005] [Indexed: 11/23/2022]
Abstract
Histamine H(3) receptor antagonists are potential therapeutic agents for cognitive dysfunction, epilepsy, hypersomnia and obesity. GT-2331 (4-[(R,R)-2-(5,5-dimethyl-1-hexynyl)cyclopropyl]-1H-imidazole) was originally identified as a potent histamine H(3) receptor antagonist. However, recent reports demonstrated a complex pharmacology for GT-2331. To further understand the pharmacological profile of GT-2331, we characterized GT-2331 using various in vitro and in vivo assays. In vitro, GT-2331 behaved as a full agonist on adenylyl cyclase inhibition and as a partial agonist on [(35)S]GTPgammaS binding at the recombinant rat histamine H(3) receptor. In contrast, in vivo, GT-2331 had no effect on brain histamine turnover while the histamine H(3) receptor agonist R-alpha-methylhistamine significantly decreased histamine turnover. Furthermore, GT-2331 completely blocked R-alpha-methylhistamine-induced water intake, suggesting that GT-2331 behaves as a full antagonist. Thus, GT-2331 displayed the spectrum of pharmacological activities from full agonism to full antagonism, these observations suggest that histamine H(3) receptor ligands need to be carefully evaluated in various paradigms.
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Affiliation(s)
- Sayaka Ito
- Tsukuba Research Institute, Banyu Pharmaceutical Co., Ltd., Tsukuba, Ibaraki 300-2611, Japan
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109
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Lorenzi S, Mor M, Bordi F, Rivara S, Rivara M, Morini G, Bertoni S, Ballabeni V, Barocelli E, Plazzi PV. Validation of a histamine H3 receptor model through structure-activity relationships for classical H3 antagonists. Bioorg Med Chem 2005; 13:5647-57. [PMID: 16085419 DOI: 10.1016/j.bmc.2005.05.072] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/18/2005] [Indexed: 10/25/2022]
Abstract
Histamine H(3) receptor is a G protein-coupled receptor whose activation inhibits the synthesis and release of histamine and other neurotransmitters from nerve endings and is involved in the modulation of different central nervous system functions. H(3) antagonists have been proposed for their potential usefulness in diseases characterized by impaired neurotransmission and they have demonstrated beneficial effects on learning and food intake in animal models. In the present work, a 3D model of the rat histamine H(3) receptor, built by comparative modeling from the crystallographic coordinates of bovine rhodopsin, is presented with the discussion of its ability to predict the potency of known and new H(3) antagonists. A putative binding site for classical, imidazole-derived H(3) antagonists was identified by molecular docking. Comparison with a known pharmacophore model and the binding affinity of a new rigid H(3) antagonist (compound 1, pK(i)=8.02) allowed the characterization of a binding scheme which could also account for the different affinities observed in a recently reported series of potent H(3) antagonists, characterized by a 2-aminobenzimidazole moiety. Molecular dynamics simulations were employed to assess the stability and reliability of the proposed binding mode. Two new conformationally constrained benzimidazole derivatives were prepared and their binding affinity was tested on rat brain membranes; compound 9, designed to reproduce the conformation of a known potent H(3) antagonist, showed higher potency than compound 8, as expected from the binding scheme hypothesized.
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Affiliation(s)
- Simone Lorenzi
- Dipartimento Farmaceutico, Università degli Studi di Parma, Parco Area delle Scienze 27/A, I-43100 Parma, Italy
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110
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Badenhorst HE, Maharaj DS, Malan SF, Daya S, van Dyk S. Histamine-3 receptor antagonists reduce superoxide anion generation and lipid peroxidation in rat brain homogenates. J Pharm Pharmacol 2005; 57:781-5. [PMID: 15969934 DOI: 10.1211/0022357056064] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Abstract
Using a cyanide model to induce neurotoxic effects in rat brain homogenates, we examined the neuroprotective properties of three H3 antagonists, namely clobenpropit, thioperamide and impentamine, and compared them to aspirin, a known neuroprotective agent. Superoxide anion levels and malondialdehyde concentration were assessed using the nitroblue tetrazolium and lipid peroxidation assays. Clobenpropit and thioperamide significantly reduced superoxide anion generation and lipid peroxidation. Impentamine reduced lipid peroxidation at all concentrations used, but only reduced superoxide anion generation at a concentration of 1 mM. In the lipid peroxidation assay, all the drugs compared favourably to aspirin. This study demonstrates the potential of these agents to be neuroprotective by exerting antioxidant effects.
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Affiliation(s)
- H E Badenhorst
- Pharmaceutical Chemistry, School of Pharmacy, North-West University, Potchefstroom 2520, South Africa
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111
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Gfesser GA, Faghih R, Bennani YL, Curtis MP, Esbenshade TA, Hancock AA, Cowart MD. Structure–activity relationships of arylbenzofuran H3 receptor antagonists. Bioorg Med Chem Lett 2005; 15:2559-63. [PMID: 15863316 DOI: 10.1016/j.bmcl.2005.03.047] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2005] [Accepted: 03/14/2005] [Indexed: 11/21/2022]
Abstract
An SAR study of histamine H3 receptor antagonists based on substituted (R)-2-methyl-1-[2-(5-phenyl-benzofuran-2-yl)-ethyl]-pyrrolidines is presented.
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Affiliation(s)
- Gregory A Gfesser
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, 100 Abbott Park Road, Abbott Park, IL 60064, USA.
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112
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Fox GB, Esbenshade TA, Pan JB, Radek RJ, Krueger KM, Yao BB, Browman KE, Buckley MJ, Ballard ME, Komater VA, Miner H, Zhang M, Faghih R, Rueter LE, Bitner RS, Drescher KU, Wetter J, Marsh K, Lemaire M, Porsolt RD, Bennani YL, Sullivan JP, Cowart MD, Decker MW, Hancock AA. Pharmacological Properties of ABT-239 [4-(2-{2-[(2R)-2-Methylpyrrolidinyl]ethyl}-benzofuran-5-yl)benzonitrile]: II. Neurophysiological Characterization and Broad Preclinical Efficacy in Cognition and Schizophrenia of a Potent and Selective Histamine H3 Receptor Antagonist. J Pharmacol Exp Ther 2004; 313:176-90. [PMID: 15608077 DOI: 10.1124/jpet.104.078402] [Citation(s) in RCA: 210] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Acute pharmacological blockade of central histamine H3 receptors (H3Rs) enhances arousal/attention in rodents. However, there is little information available for other behavioral domains or for repeated administration using selective compounds. ABT-239 [4-(2-{2-[(2R)-2-methylpyrrolidinyl]ethyl}-benzofuran-5-yl)benzonitrile] exemplifies such a selective, nonimidazole H3R antagonist with high affinity for rat (pK(i) = 8.9) and human (pK(i) = 9.5) H3Rs. Acute functional blockade of central H3Rs was demonstrated by blocking the dipsogenia response to the selective H3R agonist (R)-alpha-methylhistamine in mice. In cognition studies, acquisition of a five-trial, inhibitory avoidance test in rat pups was improved with ABT-239 (0.1-1.0 mg/kg), a 10- to 150-fold gain in potency, with similar efficacy, over previous antagonists such as thioperamide, ciproxifan, A-304121 [(4-(3-(4-((2R)-2-aminopropanoyl)-1-piperazinyl)propoxy)phenyl)(cyclopropyl) methanone], A-317920 [N-((1R)-2-(4-(3-(4-(cyclopropylcarbonyl) phenoxy)propyl)-1-piperazinyl)-1-methyl-2-oxoethyl)-2-furamide], and A-349821 [(4'-(3-((R,R)2,5-dimethyl-pyrrolidin-1-yl)-propoxy)-biphenyl-4-yl)-morpholin-4-yl-methanone]. Efficacy in this model was maintained for 3 to 6 h and following repeated dosing with ABT-239. Social memory was also improved in adult (0.01-0.3 mg/kg) and aged (0.3-1.0 mg/kg) rats. In schizophrenia models, ABT-239 improved gating deficits in DBA/2 mice using prepulse inhibition of startle (1.0-3.0 mg/kg) and N40 (1.0-10.0 mg/kg). Furthermore, ABT-239 (1.0 mg/kg) attenuated methamphetamine-induced hyperactivity in mice. In freely moving rat microdialysis studies, ABT-239 enhanced acetylcholine release (0.1-3.0 mg/kg) in adult rat frontal cortex and hippocampus and enhanced dopamine release in frontal cortex (3.0 mg/kg), but not striatum. In summary, broad efficacy was observed with ABT-239 across animal models such that potential clinical efficacy may extend beyond disorders such as ADHD to include Alzheimer's disease and schizophrenia.
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Affiliation(s)
- Gerard B Fox
- Neuroscience Research, Global Pharmaceutical Research Division, Abbott Laboratories, AP9A, R4N5, Abbott Park, IL 60064-6115, USA.
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113
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Esbenshade TA, Fox GB, Krueger KM, Miller TR, Kang CH, Denny LI, Witte DG, Yao BB, Pan L, Wetter J, Marsh K, Bennani YL, Cowart MD, Sullivan JP, Hancock AA. Pharmacological properties of ABT-239 [4-(2-{2-[(2R)-2-Methylpyrrolidinyl]ethyl}-benzofuran-5-yl)benzonitrile]: I. Potent and selective histamine H3 receptor antagonist with drug-like properties. J Pharmacol Exp Ther 2004; 313:165-75. [PMID: 15608078 DOI: 10.1124/jpet.104.078303] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Histamine H3 receptor antagonists are being developed to treat a variety of neurological and cognitive disorders that may be ameliorated by enhancement of central neurotransmitter release. Here, we present the in vitro pharmacological and in vivo pharmacokinetic profiles for the nonimidazole, benzofuran ligand ABT-239 [4-(2-{2-[(2R)-2-methylpyrrolidinyl]ethyl}-benzofuran-5-yl)benzonitrile] and compare it with several previously described imidazole and nonimidazole H3 receptor antagonists. ABT-239 binds to recombinant human and rat H3 receptors with high affinity, with pK(i) values of 9.4 and 8.9, respectively, and is over 1000-fold selective versus human H1, H2, and H4 histamine receptors. ABT-239 is a potent H3 receptor antagonist at recombinant human and rat receptors, reversing agonist-induced changes in cAMP formation (pK(b) = 7.9 and 7.6, respectively), guanosine 5'-O-(3-[35S]thio) triphosphate ([35S]GTPgammaS) binding (pK(b) = 9.0 and 8.3, respectively), and calcium mobilization (human pK(b) = 7.9). ABT-239 also competitively reversed histamine-mediated inhibition of [3H]histamine release from rat brain cortical synaptosomes (pK(b) = 7.7) and agonist-induced inhibition of contractile responses in electric field stimulated guinea pig ileal segments (pA2 = 8.7). Additionally, ABT-239 is a potent inverse agonist, inhibiting constitutive [35S]GTPgammaS binding at both rat and human H3 receptors with respective pEC50 values of 8.9 and 8.2. ABT-239 demonstrates good pharmacokinetic characteristics in rat, dog, and monkey with t1/2 values ranging from 4 to 29 h, corresponding with clearance values and metabolic turnover in liver microsomes from these species, and good oral bioavailability ranging from 52 to 89%. Thus, ABT-239 is a selective, nonimidazole H3 receptor antagonist/inverse agonist with similar high potency in both human and rat and favorable drug-like properties.
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Affiliation(s)
- Timothy A Esbenshade
- Neuroscience Research, Abbott Laboratories, R4MN, AP9A, 100 Abbott Park Road, Abbott Park, IL 60064, USA.
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114
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Passani MB, Lin JS, Hancock A, Crochet S, Blandina P. The histamine H3 receptor as a novel therapeutic target for cognitive and sleep disorders. Trends Pharmacol Sci 2004; 25:618-25. [PMID: 15530639 DOI: 10.1016/j.tips.2004.10.003] [Citation(s) in RCA: 172] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Histamine H3 receptor pharmacology, functions and biochemistry are far from being fully understood; however, progress is being made. Activation of this Gi/GO-protein-coupled receptor affects cognition, the sleep-wake cycle, obesity and epilepsy, which are physiological and pathological conditions that are the main focus of research into the therapeutic potential of selective H3 receptor ligands. This heterogeneity of targets can be reconciled partially by the fact that the histamine system constitutes one of the most important brain-activating systems and that H3 receptors regulate the activity of histamine and other neurotransmitter systems. Furthermore, the H3 receptor shows functional constitutive activity, polymorphisms in humans and rodents with a differential distribution of splice variants in the CNS, and potential coupling to different intracellular signal transduction mechanisms. In light of the genetic, pharmacological and functional complexity of the H3 receptor, the importance of the histamine system as a therapeutic target to control the sleep-wake cycle and cognitive disorders will be discussed.
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Affiliation(s)
- Maria Beatrice Passani
- Dipartimento di Farmacologia Preclinica e Clinica, Universitá di Firenze, Viale Pieraccini 6, 50139 Firenze, Italy
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