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Kou E, Zhang X, Dong B, Wang B, Zhu Y. Combination of H1 and H2 Histamine Receptor Antagonists: Current Knowledge and Perspectives of a Classic Treatment Strategy. Life (Basel) 2024; 14:164. [PMID: 38398673 PMCID: PMC10890042 DOI: 10.3390/life14020164] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 01/19/2024] [Accepted: 01/20/2024] [Indexed: 02/25/2024] Open
Abstract
Histamine receptor antagonists, which can bind to specific histamine receptors on target cells, exhibit substantial therapeutic efficacy in managing a variety of histamine-mediated disorders. Notably, histamine H1 and H2 receptor antagonists have been extensively investigated and universally acknowledged as recommended treatment agents for numerous allergic diseases and acid-related disorders, respectively. Historically, the combination of H1 and H2 receptor antagonists has been considered a classic treatment strategy, demonstrating relatively superior efficacy compared with single-drug therapies in the treatment of diverse histamine-mediated diseases. The latest emerging studies have additionally suggested the underlying roles of histamine and H1R and H2R in the development of anxiety disorders, arthritic diseases, and postexercise hypotension. Nevertheless, there is still a lack of systematic reviews on the clinical efficacy of combination therapy, greatly limiting our understanding of its clinical application. Here, we present a comprehensive overview of the current knowledge and perspectives regarding the combination of H1 and H2 histamine receptor antagonists in various histamine-mediated disorders. Furthermore, we critically analyze the adverse effects and limitations associated with combination therapy while suggesting potential solutions. Our review can offer a systematic summary and promising insights into the in-depth and effective application of the combination of H1 and H2 receptor antagonists.
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Affiliation(s)
- Erwen Kou
- Department of Dermatology, Naval Medical Center, Naval Medical University, Shanghai 200052, China; (E.K.); (B.D.)
| | - Xiaobei Zhang
- Department of Pharmacy, Naval Medical Center, Naval Medical University, Shanghai 200052, China;
| | - Baiping Dong
- Department of Dermatology, Naval Medical Center, Naval Medical University, Shanghai 200052, China; (E.K.); (B.D.)
| | - Bo Wang
- Department of Dermatology, Naval Medical Center, Naval Medical University, Shanghai 200052, China; (E.K.); (B.D.)
| | - Yuanjie Zhu
- Department of Dermatology, Naval Medical Center, Naval Medical University, Shanghai 200052, China; (E.K.); (B.D.)
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Arumuham A, Nour MM, Veronese M, Onwordi EC, Rabiner EA, Howes OD. The histamine system and cognitive function: An in vivo H3 receptor PET imaging study in healthy volunteers and patients with schizophrenia. J Psychopharmacol 2023; 37:1011-1022. [PMID: 37329185 PMCID: PMC10612380 DOI: 10.1177/02698811231177287] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
BACKGROUND The histamine-3 receptor (H3R) is an auto- and heteroreceptor that inhibits the release of histamine and other neurotransmitters. Post-mortem evidence has found altered H3R expression in patients with psychotic disorders, which may underlie cognitive impairment associated with schizophrenia (CIAS). AIMS We used positron emission tomography (PET) imaging to compare brain uptake of an H3R selective tracer between patients with schizophrenia and matched controls (healthy individuals). Regions of interest included the dorsolateral prefrontal cortex (DLPFC) and striatum. We explored correlations between tracer uptake and symptoms, including cognitive domains. METHODS A total of 12 patients and 12 matched controls were recruited to the study and were assessed with psychiatric and cognitive rating scales. They received a PET scan using the H3R-specific radioligand [11C]MK-8278 to determine H3R availability. RESULTS There was no statistically significant difference in tracer uptake between patients and controls in the DLPFC (t19 = 0.79, p = 0.44) or striatum (t21 = 1.18, p = 0.25). An exploratory analysis found evidence for lower volume of distribution in the left cuneus (pFWE-corrected = 0.01). DLPFC tracer uptake was strongly correlated with cognition in controls (trail making test (TMT) A: r = 0.77, p = 0.006; TMT B: rho = 0.74, p = 0.01), but not in patients (TMT A: r = -0.18, p = 0.62; TMT B: rho = -0.06, p = 0.81). CONCLUSIONS These findings indicate H3R in the DLPFC might play a role in executive function and this is disrupted in schizophrenia in the absence of major alterations in H3R availability as assessed using a selective radiotracer for H3R. This provides further evidence for the role of H3R in CIAS.
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Affiliation(s)
- Atheeshaan Arumuham
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, London, UK
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK
- Psychiatric Imaging Group, Medical Research Council, London Institute of Medical Sciences, Hammersmith Hospital, London, UK
| | - Matthew M Nour
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, London, UK
- Department of Psychiatry, University of Oxford, Oxford, UK
- Max Planck University College London Centre for Computational Psychiatry and Ageing Research, London, UK
| | - Mattia Veronese
- Department of Information Engineering, University of Padua, Padua, Italy
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
| | - Ellis Chika Onwordi
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, London, UK
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK
- Psychiatric Imaging Group, Medical Research Council, London Institute of Medical Sciences, Hammersmith Hospital, London, UK
- Centre for Psychiatry and Mental Health, Wolfson Institute of Population Health, Queen Mary University of London, London, UK
| | - Eugenii A Rabiner
- Department of Neuroimaging, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, UK
- Invicro, London, UK
| | - Oliver D Howes
- Department of Psychosis Studies, Institute of Psychiatry, Psychology & Neuroscience, Kings College London, London, UK
- Institute of Clinical Sciences, Faculty of Medicine, Imperial College London, London, UK
- Psychiatric Imaging Group, Medical Research Council, London Institute of Medical Sciences, Hammersmith Hospital, London, UK
- H Lundbeck A/s, St Albans, UK
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Alhusaini M, Eissa N, Saad AK, Beiram R, Sadek B. Revisiting Preclinical Observations of Several Histamine H3 Receptor Antagonists/Inverse Agonists in Cognitive Impairment, Anxiety, Depression, and Sleep-Wake Cycle Disorder. Front Pharmacol 2022; 13:861094. [PMID: 35721194 PMCID: PMC9198498 DOI: 10.3389/fphar.2022.861094] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Accepted: 04/22/2022] [Indexed: 12/25/2022] Open
Abstract
A relationship appears to exist between dysfunction of brain histamine (HA) and various neuropsychiatric brain disorders. The possible involvement of brain HA in neuropathology has gained attention recently, and its role in many (patho)physiological brain functions including memory, cognition, and sleep-wake cycle paved the way for further research on the etiology of several brain disorders. Histamine H3 receptor (H3R) evidenced in the brains of rodents and humans remains of special interest, given its unique position as a pre- and postsynaptic receptor, controlling the synthesis and release of HA as well as different other neurotransmitters in different brain regions, respectively. Despite several disappointing outcomes for several H3R antagonists/inverse agonists in clinical studies addressing their effectiveness in Alzheimer's disease (AD), Parkinson's disease (PD), and schizophrenia (SCH), numerous H3R antagonists/inverse agonists showed great potentials in modulating memory and cognition, mood, and sleep-wake cycle, thus suggesting its potential role in neurocognitive and neurodegenerative diseases such as AD, PD, SCH, narcolepsy, and major depression in preclinical rodent models. In this review, we present preclinical applications of selected H3R antagonists/inverse agonists and their pharmacological effects on cognitive impairment, anxiety, depression, and sleep-wake cycle disorders. Collectively, the current review highlights the behavioral impact of developments of H3R antagonists/inverse agonists, aiming to further encourage researchers in the preclinical drug development field to profile the potential therapeutic role of novel antagonists/inverse agonists targeting histamine H3Rs.
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Affiliation(s)
- Mera Alhusaini
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.,Zayed Center for Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Nermin Eissa
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.,Zayed Center for Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.,Department of Biomedical Sciences, College of Health Sciences, Abu Dhabi University, Abu Dhabi, United Arab Emirates
| | - Ali K Saad
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.,Zayed Center for Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Rami Beiram
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.,Zayed Center for Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
| | - Bassem Sadek
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.,Zayed Center for Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates
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Lehert P. Efficacy of Pitolisant 20 mg in Reducing Excessive Daytime Sleepiness and Fatigue in Patients with Obstructive Sleep Apnoea Syndrome: An Individual Patient Data Meta-analysis. Clin Drug Investig 2021; 42:65-74. [PMID: 34859394 PMCID: PMC8755655 DOI: 10.1007/s40261-021-01104-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/07/2021] [Indexed: 11/26/2022]
Abstract
Background and objective Excessive daytime sleepiness (EDS) and fatigue are major complaints in patients with obstructive sleep apnoea (OSA) syndrome. Pitolisant is an orally active selective histamine H3 receptor (H3R) antagonist/inverse agonist, which enhances histaminergic transmissions in the brain and thereby elicits strong wake-promoting effects. This article assesses the efficacy and safety of pitolisant 20 mg in patients with OSA, based on existing randomised controlled studies. Methods An individual patient data (IPD) meta-analytical two-level (study-patient) hierarchical model was used assuming a random treatment effect. The Epworth Sleepiness Scale (ESS) and Oxford Sleep Resistance (OSleR) tests were co-primary endpoints. Results A total of 512 patients, including 384 treated with pitolisant and 128 with placebo, were included in the analysis.
Compared with placebo, pitolisant reduced mean ESS by − 3.1 (95% CI [− 4.1; − 2.1]; p < 0.001) and improved OSleR by 1.18 (1.02; 1.35, p = 0.022); 30% more patients had reduced fatigue (risk ratio [RR] = 1.3, [1.11; 1.53]), p = 0.001) and 46% more patients had improved Clinical Global Impression (CGI) (RR = 1.46 [1.12; 1.89], p = 0.005). No significant differences in safety endpoints were found. These results proved homogeneous across studies and subgroups of the population. Conclusion The results provide evidence of a significant benefit of pitolisant in improving EDS and fatigue, irrespective of baseline conditions. Supplementary Information The online version contains supplementary material available at 10.1007/s40261-021-01104-8.
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Affiliation(s)
- Philippe Lehert
- Faculty of Medicine, The University of Melbourne, Parkville, VIC, Australia.
- Louvain School of Management, Louvain University, Chaussee de Binche 151/M1.01.01, 7000, Mons, Belgium.
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Structures 4-n-propyl Piperazines as Non-Imidazole Histamine H3 Antagonists. MATERIALS 2021; 14:ma14227094. [PMID: 34832494 PMCID: PMC8621284 DOI: 10.3390/ma14227094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 11/10/2021] [Accepted: 11/12/2021] [Indexed: 11/16/2022]
Abstract
Seven new low-temperature structures of 4-n-propylpiperazine derivatives, potential H3 receptor antagonists, have been determined by X-ray crystallography, with the following symmetry and unit cell parameters: 2-(4-propyl-piperazin-1-yl)oxazolo[4,5-c]pyridine (compound 1), P-1, 5.9496 Å, 12.4570 Å, 12.8656 Å, 112.445°, 95.687°, 103.040°; 2-(4-propyl-piperazin-1-yl)thia-zolo[4,5-c]pyridine (compound 2), I2/a, 22.2087 Å, 7.5519 Å, 19.9225 Å, β = 92.368°; 2-(4-propyl-piperazin-1-yl)oxazolo[5,4-c]pyridine (compound 3), C2/c, 51.1351 Å, 9.36026 Å, 7.19352 Å, β = 93.882°; 2-(4-propyl-piperazin-1-yl)thiazolo[5,4-c]pyridine (compound 4), Pbcn, 19.2189 Å, 20.6172 Å, 7.4439 Å; 2-(4-propylpiperazin-1-yl)[1,3]oxazolo[4,5-b]pyridine, hydrate (structure 5), Pbca, 7.4967 Å, 12.2531 Å, 36.9527 Å; 2-(4-propylpiperazin-1-yl)[1,3]oxazolo[4,5-b]pyridine, first polymorph (structure 6), P-1, 7.2634 Å, 11.1261 Å, 18.5460 Å, 80.561°, 80.848°, 76.840°; 2-(4-propylpiperazin-1-yl)[1,3]oxazolo[4,5-b]pyridine, second polymorph (structure 7), P21, 8.10852 Å, 7.06025 Å, 12.41650 Å, β = 92.2991°. All the compounds crystallized out as hydrobromides. Oxazole structures show a much greater tendency to form twin crystals than thiazole structures. All the investigated structures display N-H···Br hydrogen bonding. (ADME) analysis, including the assessment of absorption, distribution, metabolism, and excretion, determined the physicochemical properties, pharmacokinetics, drug similarity, and bioavailability radar, and confirmed the usefulness of the compounds in question for pharmaceutical utility. This work is a continuation of the research searching for a new lead of non-imidazole histamine H3 receptor antagonists.
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Hira S, Saleem U, Anwar F, Raza Z, Rehman AU, Ahmad B. In Silico Study and Pharmacological Evaluation of Eplerinone as an Anti-Alzheimer's Drug in STZ-Induced Alzheimer's Disease Model. ACS OMEGA 2020; 5:13973-13983. [PMID: 32566864 PMCID: PMC7301577 DOI: 10.1021/acsomega.0c01381] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 05/15/2020] [Indexed: 05/21/2023]
Abstract
UNLABELLED Alzheimer's disease (AD) is the neurodegenerative disorder characterized by impairment of higher intellectual dysfunctions associated with changes in the cognitive, behavioral, and social activities. AIM OF THE STUDY The current study was designed to evaluate the potential of aldosterone antagonist in the treatment of AD. METHODOLOGY The study was conducted on albino mice of either sex (n = 60). Mice were subcategorized into six groups, each group having 10 mice. Group I-normal control (CMC 1 mL/kg), group II-diseased [streptozotocin (STZ), 3 mg/kg, intracerebroventricular (i.c.v.)], group III-standard (piracetam, 200 mg/kg, i.p.), and groups IV-VI designated as the treatment group (eplerinone at dose levels of 4, 8, and 16 mg/kg, orally), respectively. The study was carried out for 14 consecutive days. STZ was administered through the i.c.v. route on first and third days of the study for memory impairment. The molecular docking was performed to investigate the chemical behavior of compounds to inhibit the AChE. Anti-Alzheimer's effect was assessed by using the behavioral paradigms such as passive avoidance, elevated plus maze, Morris water maze, open field, and balance beam. Various endogenous antioxidants such as SOD, GSH, nitrite, MDA, CAT, and AChE were identified in brain tissues of treated mice to assess the oxidative stress index. Biochemical markers for AD such as norepinephrine, dopamine, and serotonin, Aβ 1-40, Aβ 1-42, NF-κB, and tumor necrosis factor alpha were analyzed in brain tissues of mice. Expression of beta amyloid was observed by PCR. RESULTS The in silico study indicated the distinct mechanism of eplerinone to inhibit the AChE. The outcomes of the in vivo study manifested that eplerinone at the highest dose was found to be more effective in the treatment of AD. CONCLUSION It may be concluded from the research work that eplerinone can be effective for cognitive improvement which proposes its therapeutic effect in many neurodegenerative disorders such as AD.
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Affiliation(s)
- Sundas Hira
- Riphah
Institute of Pharmaceutical Sciences, Riphah
International University, Lahore Campus, Lahore 54000, Pakistan
| | - Uzma Saleem
- Faculty
of Pharmaceutical Sciences, GC University, Faisalabad 38000, Pakistan
| | - Fareeha Anwar
- Riphah
Institute of Pharmaceutical Sciences, Riphah
International University, Lahore Campus, Lahore 54000, Pakistan
| | - Zohaib Raza
- Faculty
of Pharmaceutical Sciences, GC University, Faisalabad 38000, Pakistan
| | - Atta Ur Rehman
- Department
of Pharmacy, Faculty of Natural Sciences, Forman Christian College (a Chartered University), Ferozpur Road, Lahore 54600, Pakistan
| | - Bashir Ahmad
- Riphah
Institute of Pharmaceutical Sciences, Riphah
International University, Lahore Campus, Lahore 54000, Pakistan
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Olszewska B, Stasiak A, McNaught Flores D, Fogel WA, Leurs R, Walczyński K. 4-Hydroxypiperidines and Their Flexible 3-(Amino)propyloxy Analogues as Non-Imidazole Histamine H₃ Receptor Antagonist: Further Structure⁻Activity Relationship Exploration and In Vitro and In Vivo Pharmacological Evaluation. Int J Mol Sci 2018; 19:ijms19041243. [PMID: 29671795 PMCID: PMC5979327 DOI: 10.3390/ijms19041243] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 04/05/2018] [Accepted: 04/17/2018] [Indexed: 11/30/2022] Open
Abstract
Presynaptic histamine H3 receptors (H3R) act as auto- or heteroreceptors controlling, respectively, the release of histamine and of other neurotransmitters in the central nervous system (CNS). The extracellular levels of several neurotransmitters are enhanced by H3R antagonists, and there is a great interest for potent, brain-penetrating H3 receptor antagonists/inverse agonists to compensate for the neurotransmitter deficits present in various neurological disorders. We have shown that 1-[(benzylfuran-2-yl)methyl]piperidinyl-4-oxyl- and benzyl- derivatives of N-propylpentan-1-amines exhibit high in vitro potencies toward the guinea pig H3 receptor (jejunum), with pA2 = 8.47 and 7.79, respectively (the reference compound used was thioperamide with pA2 = 8.67). Furthermore, following the replacement of 4-hydroxypiperidine with a 3-(methylamino)propyloxy chain, the pA2 value for the first group decreased, whereas it increased for the second group. Here, we present data on the impact of elongating the aliphatic chain between the nitrogen of 4-hydroxypiperidine or 3-(methylamino)propan-1-ol and the lipophilic residue. Additionally, the most active compound in this series of non-imidazole H3 receptor antagonists/inverse agonists, i.e., ADS-003, was evaluated for its affinity to the recombinant rat and human histamine H3 receptors transiently expressed in HEK-293T cells. It was shown that ADS-003, given parenterally for 5 days, reduced the food intake of rats, as well as changed histamine and noradrenaline concentrations in the rats’ brain in a manner and degree similar to the reference H3 antagonist Ciproxifan.
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Affiliation(s)
- Beata Olszewska
- Department of Synthesis and Technology of Drugs, Medical University of Lodz, Muszyńskiego Street 1, 90-145 Łódź, Poland.
| | - Anna Stasiak
- Department of Hormone Biochemistry, Medical University of Lodz, Żeligowskiego Street 7/9, 90-752 Łódź, Poland.
| | - Daniel McNaught Flores
- Amsterdam Institute of Molecules, Medicines & Systems, Division of Medicinal Chemistry, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands.
| | - Wiesława Agnieszka Fogel
- Department of Hormone Biochemistry, Medical University of Lodz, Żeligowskiego Street 7/9, 90-752 Łódź, Poland.
| | - Rob Leurs
- Amsterdam Institute of Molecules, Medicines & Systems, Division of Medicinal Chemistry, Vrije Universiteit Amsterdam, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands.
| | - Krzysztof Walczyński
- Department of Synthesis and Technology of Drugs, Medical University of Lodz, Muszyńskiego Street 1, 90-145 Łódź, Poland.
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Panayi F, Sors A, Bert L, Martin B, Rollin-Jego G, Billiras R, Carrié I, Albinet K, Danober L, Rogez N, Thomas JY, Pira L, Bertaina-Anglade V, Lestage P. In vivo pharmacological profile of S 38093, a novel histamine H3 receptor inverse agonist. Eur J Pharmacol 2017; 803:1-10. [DOI: 10.1016/j.ejphar.2017.03.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2016] [Revised: 03/07/2017] [Accepted: 03/10/2017] [Indexed: 11/25/2022]
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Estork DM, Gusmão DF, Paciencia ML, Frana SA, Díaz IE, Varella AD, Younes RN, Reis LF, Montero EF, Bernardi MM, Suffredini IB. Casinga-cheirosa organic extract impairment over Balb-c male mice behavioral phenotype. REVISTA BRASILEIRA DE FARMACOGNOSIA-BRAZILIAN JOURNAL OF PHARMACOGNOSY 2016. [DOI: 10.1016/j.bjp.2015.10.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Yuan M, Gao S, Sun C, Chen L, Shi Q, Hu J, Yu R, Zhou X. Inhibiting geranylgeranyltransferase I activity decreases spine density in central nervous system. Hippocampus 2014; 25:373-84. [PMID: 25330763 DOI: 10.1002/hipo.22379] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2014] [Indexed: 12/20/2022]
Abstract
Geranylgeranyltransferase I (GGT), a protein prenyltransferase, is responsible for the posttranslational lipidation of Rho GTPases, such as Rac, Rho and Cdc42, all of which play an important role in neuronal synaptogenesis. We previously demonstrated that GGT promotes dendritic morphogenesis in cultured hippocampal neurons and cerebellar slices. We report here that inhibiting GGT activity decreases basal- and activity-dependent changes in spine density as well as in learning and memory ability of mice in vivo. We found that KCl- or bicuculline-induced dendritic spine density increases was abolished by specific GGT inhibitor GGTi-2147 treatment in cultured hippocampal neurons. GGTi-2147 lateral ventricular injection reduced GGT activity and membrane association of Rac and decreased the density of dendritic spines in the mouse hippocampus, frontal cortex and cerebellum. GGTi-2147 administration also impaired learning and memory ability of mice. More importantly, mice exposed to environmental enrichment (EE) showed increased spine density and learning and memory ability, which were significantly reversed by GGTi-2147 administration. These data demonstrate that inhibiting GGT activity prevents both basal- and activity-dependent changes in spine density in central nervous system both in vitro and in vivo. Manipulating GGT activity may be a promising strategy for the therapies of neurodevelopmental disorders, such as autism, depression, and schizophrenia.
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Affiliation(s)
- Maochun Yuan
- The Graduate School, Xuzhou Medical College, Xuzhou, Jiangsu, China
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Nikolic K, Filipic S, Agbaba D, Stark H. Procognitive properties of drugs with single and multitargeting H3 receptor antagonist activities. CNS Neurosci Ther 2014; 20:613-23. [PMID: 24836924 DOI: 10.1111/cns.12279] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 04/07/2014] [Accepted: 04/07/2014] [Indexed: 01/01/2023] Open
Abstract
The histamine H3 receptor (H3 R) is an important modulator of numerous central control mechanisms. Novel lead optimizations for H3 R antagonists/inverse agonists involved studies of structure-activity relationships, cross-affinities, and pharmacokinetic properties of promising ligands. Blockade of inhibitory histamine H3 autoreceptors reinforces histaminergic transmission, while antagonism of H3 heteroreceptors accelerates the corticolimbic liberation of acetylcholine, norepinephrine, glutamate, dopamine, serotonin and gamma-aminobutyric acid (GABA). The H3 R positioned at numerous neurotransmission crossroads indicates therapeutic applications of small-molecule H3 R modulators in a number of psychiatric and neurodegenerative diseases with various clinical candidates available. Dual target drugs displaying H3 R antagonism/inverse agonism with inhibition of acetylcholine esterase (AChE), histamine N-methyltransferase (HMT), or serotonin transporter (SERT) are novel class of procognitive agents. Main chemical diversities, pharmacophores, and pharmacological profiles of procognitive agents acting as H3 R antagonists/inverse agonists and dual H3 R antagonists/inverse agonists with inhibiting activity on AChE, HMT, or SERT are highlighted here.
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Affiliation(s)
- Katarina Nikolic
- Faculty of Pharmacy, Department of Pharmaceutical Chemistry, University of Belgrade, Belgrade, Serbia
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Masłowska-Lipowicz I, Walczyński K. Structure-activity relationships of new 1-substitutedmethyl-4-[5-(N-methyl-N-propylamino)pentyloxy]piperidines and selected 1-[(N-substituted-N-methyl)-3-propyloxy]-5-(N-methy-l-N-propyl)-pentanediamines as H3 -antagonists. Chem Biol Drug Des 2013; 83:106-18. [PMID: 23957330 DOI: 10.1111/cbdd.12206] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 06/14/2013] [Accepted: 08/12/2013] [Indexed: 11/27/2022]
Abstract
Novel, potent non-imidazole histamine H3 receptor antagonists have been prepared and in vitro tested as H3 -receptor antagonists (the electrically evoked contraction of the guinea-pig jejunum). The present compounds contain a 4-hydroxypiperidine core, which behaves as a conformationally restricted version of the 3-amino-1-propanol moiety common to the many previously described non-imidazole H3 ligands. Detailed structure-activity studies revealed that 1-(2-benzofuranylmethyl)- 5c (pA2 = 8.47 ± 0.05) and 1-(3-benzofuranylmethyl)-4-[5-(N-methyl-N-propyl)pentyloxy]piperidine 5d (pA2 = 8.15 ± 0.07) exhibit high potency for the H3 histamine receptor. In addition, the potency of selected 1-[(N-substituted-N-methyl)-3-propyloxy]-5-(N-methyl-N-propyl)pentanediamines as antagonist of the H3 histamine receptor was also evaluated. Replacement of the 4-hydroxypiperidine of the leads 7 and 5c by a highly flexible 3-(methylamino)propyloxy chain yields compounds 6a (pA2 = 8.02) and 6b (pA2 = 6.23) with higher and lower potency than their piperidine analogues (7, pA2 = 7.79; 5c, pA2 = 8.47), respectively. The histaminergic H1 antagonism of selected compounds 5c, 5d and 6a has been established on the isolated guinea-pig ileum by conventional methods; the pA2 values have compared with the potency of pyrilamine. None of them showed any H1 -antagonistic activity (pA2 < 4; for pyrilamine pA2 = 8.5).
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Affiliation(s)
- Iwona Masłowska-Lipowicz
- Department of Synthesis and Technology of Drugs, Medical University, Muszyńskiego Street 1, 90-151, Łódź, Poland
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Kruk M, Miszkiel J, McCreary AC, Przegaliński E, Filip M, Biała G. Effects of the histamine H3 receptor antagonist ABT-239 on cognition and nicotine-induced memory enhancement in mice. Pharmacol Rep 2012; 64:1316-25. [DOI: 10.1016/s1734-1140(12)70929-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 08/03/2012] [Indexed: 11/16/2022]
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14
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Pharmacophore modeling, virtual screening and docking studies to identify novel HNMT inhibitors. J Taiwan Inst Chem Eng 2012. [DOI: 10.1016/j.jtice.2012.01.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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15
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McGaraughty S, Chu KL, Cowart MD, Brioni JD. Antagonism of Supraspinal Histamine H3 Receptors Modulates Spinal Neuronal Activity in Neuropathic Rats. J Pharmacol Exp Ther 2012; 343:13-20. [DOI: 10.1124/jpet.112.194761] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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16
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Staszewski M, Walczyński K. Synthesis and preliminary pharmacological investigation of new N-substituted-N-[ω-(ω-phenoxy-alkylpiperazin-1-yl)alkyl]guanidines as non-imidazole histamine H(3) antagonists. Arch Pharm (Weinheim) 2012; 345:431-43. [PMID: 22415744 DOI: 10.1002/ardp.201100428] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2011] [Revised: 01/20/2012] [Accepted: 01/24/2012] [Indexed: 11/08/2022]
Abstract
Novel, potent non-imidazole histamine H(3) receptor antagonists were prepared. Detailed structure-activity studies revealed that N-(4-trifluoromethylbenzyl)-N-[4-(7-phenoxyheptylpiperazin-1-yl)butyl]guanidine (pA(2) = 8.49 ± 0.05), 1h, and N-(4-nitrobenzyl)-N-[4-(7-phenoxyheptylpiperazin-1-yl)butyl]guanidine (pA(2) = 8.43 ± 0.05), 1l, exhibit high affinity for the H(3) histamine receptor. The most potent antagonists in this series, 1e, 1h, and 1l, were also in vitro tested as H(1) receptor antagonists, showing weak H(1) -antagonistic activity with pA(2) = 6.70 ± 0.09, pA(2) = 6.46 ± 0.09, and pA(2) = 6.65 ± 0.11, respectively.
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Affiliation(s)
- Marek Staszewski
- Department of Synthesis and Technology of Drugs, Medical University, Łódź, Poland
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Protective effects of histamine H3-receptor ligands in schizophrenic behaviors in experimental models. Pharmacol Rep 2012; 64:191-204. [DOI: 10.1016/s1734-1140(12)70746-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2010] [Revised: 08/31/2011] [Indexed: 11/24/2022]
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18
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Histaminergic mechanisms for modulation of memory systems. Neural Plast 2011; 2011:328602. [PMID: 21876818 PMCID: PMC3160014 DOI: 10.1155/2011/328602] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Accepted: 06/29/2011] [Indexed: 12/31/2022] Open
Abstract
Encoding for several memory types requires neural changes and the activity of distinct regions across the brain. These areas receive broad projections originating in nuclei located in the brainstem which are capable of modulating the activity of a particular area. The histaminergic system is one of the major modulatory systems, and it regulates basic homeostatic and higher functions including arousal, circadian, and feeding rhythms, and cognition. There is now evidence that histamine can modulate learning in different types of behavioral tasks, but the exact course of modulation and its mechanisms are controversial. In the present paper we review the involvement of the histaminergic system and the effects histaminergic receptor agonists/antagonists have on the performance of tasks associated with the main memory types as well as evidence provided by studies with knockout models. Thus, we aim to summarize the possible effects histamine has on modulation of circuits involved in memory formation.
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Blandina P, Munari L, Giannoni P, Mariottini C, Passani MB. Histamine neuronal system as a therapeutic target for the treatment of cognitive disorders. FUTURE NEUROLOGY 2010. [DOI: 10.2217/fnl.10.30] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Much has been learned over the past 20 years about the role of histamine as a neurotransmitter. This brief article attempts to evaluate the progress accomplished in this field, and discusses the therapeutic potential of the H3 receptor (H3R). All histaminergic neurons are localized in the tuberomammillary nucleus of the posterior hypothalamus and project to almost all regions of the CNS. Histamine exerts its effect via interaction with specific receptors (H1R, H2R, H3R and H4R). Antagonists of both H1R and H2R have been successful as blockbuster drugs for treating allergic conditions and gastric ulcers. H4R is still awaiting better functional characterization, but the H3R is an attractive target for potential therapies of CNS disorders. Indeed, considerable interest was raised by reports that pharmacological blockade of H3Rs exerted procognitive effects in a variety of animal tasks analyzing different types of memory. In addition, blockade of H3Rs increased wakefulness and reduced bodyweight in animal models. Such findings hint at the potential use of H3R antagonists/inverse agonists for the treatment of Alzheimer’s disease and other dementias, attention-deficit hyperactivity disorder, obesity and sleep disorders. As a result, an increasing number of H3R antagonists/inverse agonists progress through the clinic for the treatment of a variety of conditions, including attention-deficit hyperactivity disorder, cognitive disorders, narcolepsy and schizophrenia. Moreover, the use of H3R antagonists/inverse agonists that weaken traumatic memories may alleviate disorders such as post-traumatic stress syndrome, panic attacks, specific phobias and generalized anxiety. The use of H3R ligands for the treatment of neurodegenerative disorders is demonstrated in several studies, indicating a role of the histamine neurons and H3Rs in neuroprotection. Recently, direct evidence demonstrated that histaminergic neurons are organized into functionally distinct circuits, impinging on different brain regions, and displaying selective control mechanisms. This could imply independent functions of subsets of histaminergic neurons according to their respective origin and terminal projections. The possibility that H3Rs control only some of those functions implies that H3R-directed therapies may achieve selective effects, with minimal side effects, and this may increase the interest regarding this class of drugs.
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Affiliation(s)
| | - Leonardo Munari
- Dipartimento di Farmacologia Preclinica e Clinica, Universitá di Firenze, Italy
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Purón-Sierra L, Sabath E, Nuñez-Jaramillo L, Miranda MI. Blockade of nucleus basalis magnocellularis or activation of insular cortex histamine receptors disrupts formation but not retrieval of aversive taste memory. Neurobiol Learn Mem 2009; 93:216-20. [PMID: 19825424 DOI: 10.1016/j.nlm.2009.10.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 10/02/2009] [Accepted: 10/06/2009] [Indexed: 10/20/2022]
Abstract
Recent research, using several experimental models, demonstrated that the histaminergic system is clearly involved in memory formation. This evidence suggested that during different associative learning tasks, histamine receptor subtypes have opposite functions, related to the regulation of cortical cholinergic activity. Given that cortical cholinergic activity and nucleus basalis magnocellularis (NBM) integrity are needed during taste memory formation, the aim of this study was to determine the role of histamine receptors during conditioned taste aversion (CTA). We evaluated the effects of bilateral infusions of 0.5 microl of pyrilamine (100 mM), an H(1) receptor antagonist, into the NBM, or of R-alpha-methylhistamine (RAMH) (10 mM), an H(3) receptor agonist, into the insular cortex of male Sprague-Dawley rats 20 min before acquisition and/or retrieval of conditioned taste aversion. The results showed that blockade of H(1) receptors in NBM or activation of H(3) receptors in the insular cortex impairs formation but not retrieval of aversive taste memory. These results demonstrated differential roles for histamine receptors in two important areas for taste memory formation and suggest that these effects could be related with the cortical cholinergic activity modulation during CTA acquisition.
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Affiliation(s)
- Liliana Purón-Sierra
- Departamento de Neurobiología Conductual y Cognitiva, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Campus Juriquilla, Boulevard Juriquilla, No. 3001 Juriquilla, Querétaro, Qro. 76230, Mexico
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21
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Kim K, Park S, Yoo HK, Lee JY, Jung HY, Kim DH, Lee HJ, Kim JY, Youn YC, Marshall MR, Kim SS, Jeong Y. Brain Factor-7 Extracted from Bombyx mori Enhances Cognition and Attention in Normal Children. J Med Food 2009; 12:643-8. [DOI: 10.1089/jmf.2008.1236] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Kunwoo Kim
- Department of Psychiatry, College of Medicine, University of Ulsan, Asan Medical Center, Seoul, Republic of Korea
| | - Subin Park
- Department of Psychiatry, College of Medicine, University of Ulsan, Asan Medical Center, Seoul, Republic of Korea
| | - Hanik K. Yoo
- Department of Psychiatry, College of Medicine, University of Ulsan, Asan Medical Center, Seoul, Republic of Korea
| | - Jun-Young Lee
- Department of Psychiatry, College of Medicine, Seoul National University, Seoul Municipal Boramae Hospital, Seoul, Republic of Korea
| | - Hee-Yeon Jung
- Department of Psychiatry, College of Medicine, Seoul National University, Seoul Municipal Boramae Hospital, Seoul, Republic of Korea
| | - Do-Hee Kim
- Department of Anatomy and Cell Biology, Chung-Ang University, Seoul, Republic of Korea
| | - Hyun-Jung Lee
- Department of Anatomy and Cell Biology, Chung-Ang University, Seoul, Republic of Korea
| | - Jin-Young Kim
- Department of Anatomy and Cell Biology, Chung-Ang University, Seoul, Republic of Korea
| | - Young-Chul Youn
- Department of Neurology, College of Medicine, Chung-Ang University, Seoul, Republic of Korea
| | - Maurice R. Marshall
- Department of Food Science and Human Nutrition, University of Florida, Gainesville, Florida
| | - Sung-Su Kim
- Department of Anatomy and Cell Biology, Chung-Ang University, Seoul, Republic of Korea
| | - Yoonhwa Jeong
- Department of Food Science and Nutrition, College of Natural Science, Dankook University, Gyeonggi-do, Republic of Korea
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22
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H3 receptor antagonists reverse delay-dependent deficits in novel object discrimination by enhancing retrieval. Psychopharmacology (Berl) 2009; 202:141-52. [PMID: 18493749 DOI: 10.1007/s00213-008-1171-2] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2007] [Accepted: 04/04/2008] [Indexed: 10/22/2022]
Abstract
RATIONALE Accumulated evidence suggests a role for histamine in cognition and the use of H3 receptor antagonists in the treatment of learning and memory disorders. OBJECTIVES The aim of the current study was to investigate the cognition enhancing properties of ciproxifan, an H3 receptor antagonist, after natural forgetting in normal adult rats. MATERIALS AND METHODS The novel object discrimination task, a recognition memory test based on spontaneous exploratory behaviour, was used. Briefly, rats exposed to two identical objects during an acquisition trial can discriminate between a novel object and a familiar one during a subsequent choice trial after a short delay but not after a 24-h inter-trial interval. RESULTS The scopolamine (0.5 mg/kg, i.p.)-induced impairment after a short delay was abolished by ciproxifan (p < 0.001). Natural forgetting was prevented by a single administration of ciproxifan (3 mg/kg) prior to the retention test (p < 0.001) but not when administered before or immediately after the acquisition trial (schedule effect p < 0.05), demonstrating a specific activity on memory retrieval. Pretreatment with either pyrilamine (10 mg/kg), an H1 antagonist, or zolantidine (10 mg/kg), an H2 antagonist, prevented the retrieval enhancement effect of ciproxifan (p < 0.05 and p < 0.001, respectively). CONCLUSIONS Histamine H3 receptor antagonists restore the performance of rats impaired by scopolamine and enhance recognition memory after acute administration before the retrieval phase via a mechanism dependent on H1 and H2 receptor activation.
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Maslowska-Lipowicz I, Figlus M, Zuiderveld OP, Walczynski K. New 1-benzyl-4-hydroxypiperidine derivatives as non-imidazole histamine H3 receptor antagonists. Arch Pharm (Weinheim) 2008; 341:762-73. [PMID: 19009544 DOI: 10.1002/ardp.200800070] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A series of 1-benzyl-4-(3-aminopropyloxy)piperidine and 1-benzyl-4-(5-aminopentyloxy)piperidine derivatives has been prepared. The 1-benzyl-4-hydroxypiperidine derivatives obtained were evaluated for their affinities at recombinant human histamine H(3 )receptor, stably expressed in HEK 293T cells. All compounds investigated show moderate to pronounced in-vitro affinities. The most potent antagonists in this series 9b2 (hH(3)R, pK(i) = 7.09), 9b1 (hH(3)R, pK(i) = 6.78), 9b5 (hH(3)R, pK(i) = 6.99), and 9b6 (hH(3)R, pK(i )= 6.97) were also tested in vitro as H(3 )receptor antagonists - the electrically evoked contraction of the guinea-pig jejunum. The histaminergic H(1) antagonism of selected compounds 9b1, 9b2, and 9b4-9b6 was established on the isolated guinea-pig ileum by conventional methods; the pA(2) values were compared with the potency of pyrilamine. The compounds did not show any H(1) antagonistic activity (pA(2) < 4; for pyrilamine pA(2) = 9.53).
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Liu LL, Yang J, Lei GF, Wang GJ, Wang YW, Sun RP. Atomoxetine increases histamine release and improves learning deficits in an animal model of attention-deficit hyperactivity disorder: the spontaneously hypertensive rat. Basic Clin Pharmacol Toxicol 2008; 102:527-32. [PMID: 18346050 DOI: 10.1111/j.1742-7843.2008.00230.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Substantial development in the pharmacological treatment for attention-deficit hyperactivity disorder (ADHD) has been made recently including approval of new non-stimulant agents targeting noradrenergic, histaminergic and dopaminergic systems. Among such, atomoxetine has been widely used, although its mechanism of action is poorly understood. It is known that central nervous system histamine is closely associated with cognition and it was recently shown that both atomoxetine and methylphenidate enhance cortical histamine release in rats. To that end, the aim of our study was to investigate the effect of atomoxetine (2 mg/kg, intraperitoneally) on histamine release using the microdialysis technique in the spontaneously hypertensive rat (SHR), a suitable genetic model for ADHD. Our data confirmed that atomoxetine increases extracellular levels of histamine in the prefrontal cortex, a brain region that is implicated in the pathophysiology of ADHD. Given the tie between histamine neurotransmission and treatment of cognitive dysfunction, we also assessed the effects of atomoxetine on learning and memory as measured by the Morris water maze in SHR. The results indicated that atomoxetine significantly ameliorated performance in the Morris water maze, consistent with its histamine-enhancing profile. In conclusion, the current study provides further support for the notion that the therapeutic effect of atomoxetine could involve activation of histamine neurotransmission within the prefrontal cortex.
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Affiliation(s)
- Li-Li Liu
- Department of Pediatrics, Qilu Hospital of Shandong University, Jinan, China
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25
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Sander K, Kottke T, Stark H. Histamine H3 Receptor Antagonists Go to Clinics. Biol Pharm Bull 2008; 31:2163-81. [DOI: 10.1248/bpb.31.2163] [Citation(s) in RCA: 162] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Kerstin Sander
- Johann Wolfgang Goethe-Universität Frankfurt am Main, Institut für Pharmazeutische Chemie
| | - Tim Kottke
- Johann Wolfgang Goethe-Universität Frankfurt am Main, Institut für Pharmazeutische Chemie
| | - Holger Stark
- Johann Wolfgang Goethe-Universität Frankfurt am Main, Institut für Pharmazeutische Chemie
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26
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Wijtmans M, Leurs R, de Esch I. Histamine H3 receptor ligands break ground in a remarkable plethora of therapeutic areas. Expert Opin Investig Drugs 2007; 16:967-85. [PMID: 17594183 DOI: 10.1517/13543784.16.7.967] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The neurotransmitter histamine exerts its action through four distinct histamine receptors. The histamine H(1) and H(2) receptor are well established drug targets, whereas the histamine H(4) receptor is undergoing rigorous characterisation at present. The histamine H(3) receptor (H(3)R) is a G(i/o)-protein coupled receptor and is mostly expressed in the CNS. A remarkably large and different array of therapeutic areas, in which ligands for the H(3)R may prove useful, has been identified and a massive research undertaking is underway to substantiate the high expectations for H(3)R ligands. At present, several ligands for the H(3)R are being evaluated in clinical studies. In this review, the many potential therapeutic areas for H(3)R antagonists, inverse agonists and agonists is discussed. Promising medicinal chemistry and toxicological developments, as well as the advancement of several H(3)R ligands into the clinic, will be highlighted. This review also describes the problems that have been overcome and the questions that remain in developing H(3)R-related drugs. Considering the tremendous efforts by industry, it can be expected that the first H(3)R drugs will reach the market soon.
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Affiliation(s)
- Maikel Wijtmans
- Vrije Universiteit Amsterdam, Leiden/Amsterdam Center of Drug Research, Division of Medicinal Chemistry, Faculty of Sciences, De Boelelaan 1083, Amsterdam, The Netherlands
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Medhurst AD, Briggs MA, Bruton G, Calver AR, Chessell I, Crook B, Davis JB, Davis RP, Foley AG, Heslop T, Hirst WD, Medhurst SJ, Ociepka S, Ray A, Regan CM, Sargent B, Schogger J, Stean TO, Trail BK, Upton N, White T, Orlek B, Wilson DM. Structurally novel histamine H3 receptor antagonists GSK207040 and GSK334429 improve scopolamine-induced memory impairment and capsaicin-induced secondary allodynia in rats. Biochem Pharmacol 2007; 73:1182-94. [PMID: 17276409 DOI: 10.1016/j.bcp.2007.01.007] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2006] [Revised: 12/13/2006] [Accepted: 01/03/2007] [Indexed: 11/25/2022]
Abstract
GSK207040 (5-[(3-cyclobutyl-2,3,4,5-tetrahydro-1H-3-benzazepin-7-yl)oxy]-N-methyl-2-pyrazinecarboxamide) and GSK334429 (1-(1-methylethyl)-4-({1-[6-(trifluoromethyl)-3-pyridinyl]-4-piperidinyl}carbonyl)hexahydro-1H-1,4-diazepine) are novel and selective non-imidazole histamine H(3) receptor antagonists from distinct chemical series with high affinity for human (pK(i)=9.67+/-0.06 and 9.49+/-0.09, respectively) and rat (pK(i)=9.08+/-0.16 and 9.12+/-0.14, respectively) H(3) receptors expressed in cerebral cortex. At the human recombinant H(3) receptor, GSK207040 and GSK334429 were potent functional antagonists (pA(2)=9.26+/-0.04 and 8.84+/-0.04, respectively versus H(3) agonist-induced changes in cAMP) and exhibited inverse agonist properties (pIC(50)=9.20+/-0.36 and 8.59+/-0.04 versus basal GTPgammaS binding). Following oral administration, GSK207040 and GSK334429 potently inhibited cortical ex vivo [(3)H]-R-alpha-methylhistamine binding (ED(50)=0.03 and 0.35 mg/kg, respectively). Functional antagonism of central H(3) receptors was demonstrated by blockade of R-alpha-methylhistamine-induced dipsogenia in rats (ID(50)=0.02 and 0.11 mg/kg p.o. for GSK207040 and GSK334429, respectively). In more pathophysiologically relevant pharmacodynamic models, GSK207040 (0.1, 0.3, 1 and 3mg/kg p.o.) and GSK334429 (0.3, 1 and 3mg/kg p.o.) significantly reversed amnesia induced by the cholinergic antagonist scopolamine in a passive avoidance paradigm. In addition, GSK207040 (0.1, 0.3 and 1mg/kg p.o.) and GSK334429 (3 and 10mg/kg p.o.) significantly reversed capsaicin-induced reductions in paw withdrawal threshold, suggesting for the first time that blockade of H(3) receptors may be able to reduce tactile allodynia. Novel H(3) receptor antagonists such as GSK207040 and GSK334429 may therefore have therapeutic potential not only in dementia but also in neuropathic pain.
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Affiliation(s)
- Andrew D Medhurst
- Neurology and GI Centre of Excellence for Drug Discovery, GlaxoSmithKline, Third Avenue, Harlow, Essex CM19 5AW, UK.
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Affiliation(s)
- Patrizio Blandina
- Dipartimento di Farmacologia Preclinica e Clinica, Università di Firenze, Italy.
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Velísek L. Prenatal exposure to betamethasone decreases anxiety in developing rats: hippocampal neuropeptide y as a target molecule. Neuropsychopharmacology 2006; 31:2140-9. [PMID: 16407893 DOI: 10.1038/sj.npp.1301016] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Repeated antenatal administration of betamethasone is frequently used as a life-saving treatment in obstetrics. However, limited information is available about the outcome of this therapy in children. The initial prospective studies indicate that there are behavioral impairments in children exposed to repeated courses of prenatal betamethasone during the third trimester of pregnancy. In this study, pregnant rats received two betamethasone injections on day 15 of gestation. Using immunohistochemistry, the expression of a powerful anxiolytic molecule neuropeptide Y (NPY) was determined on postnatal day (PN) 20 in the hippocampus and basolateral amygdala (structures related to anxiety and fear) of the offspring. Prenatal betamethasone exposure induced significant increases in NPY expression in the hippocampus but not in the amygdala. Indeed, behavioral tests in the offspring, between PN20 and PN22 in the open field, on the horizontal bar, and in the elevated plus maze, indicated decreases in anxiety, without impairments in motor performance or total activity. Decreased body weight in betamethasone-exposed rats confirmed long-lasting effects of prenatal exposure. Thus, prenatal betamethasone treatment consistently increases hippocampal NPY, with decreases in anxiety-related behaviors and hippocampal role in anxiety in rats. Animal models may assist in differentiation between pathways of the desired main effect of the antenatal corticosteroid treatment and pathways of unwanted side effects. This differentiation can lead to specific therapeutic interventions directed against the side effects without eliminating the beneficial main effect of the corticosteroid treatment.
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Affiliation(s)
- Libor Velísek
- Department of Neurology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
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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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31
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Hancock AA, Fox GB. Perspectives on cognitive domains, H3 receptor ligands and neurological disease. Expert Opin Investig Drugs 2006; 13:1237-48. [PMID: 15461554 DOI: 10.1517/13543784.13.10.1237] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Histamine H(3) receptor agonists and antagonists have been evaluated in numerous in vitro and in vivo animal models to better understand how H(3) receptors modulate neurotransmitter function in the central nervous system. Likewise, behavioural models have explored the hypothesis that changes in neurotransmitter release could enhance cognitive function in human diseases. This review examines the reported effects of H(3) receptor ligands and how they influence cognitive behaviour. These data are interpreted on the basis of different cognitive domains that are relevant to neuropsychiatric diseases. Because of the diversity of H(3) receptors, their function and their influence on neurotransmitter systems, considerable promise exists for H(3) ligands to treat diseases in which aspects of learning and memory are impaired. However, because of the complexities of the histaminergic system and H(3) receptors and the lack of clinical data so far, proof of principle for use in human disease remains to be established.
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Affiliation(s)
- Arthur A Hancock
- Abbott Laboratories, Department R4MN, Building AP9A/3, Neuroscience Division, 100 Abbott Park Road, Abbott Park, IL 60064-6125, USA.
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32
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Govoni M, Lim HD, El-Atmioui D, Menge WMPB, Timmerman H, Bakker RA, Leurs R, De Esch IJP. A Chemical Switch for the Modulation of the Functional Activity of Higher Homologues of Histamine on the Human Histamine H3 Receptor: Effect of Various Substitutions at the Primary Amino Function. J Med Chem 2006; 49:2549-57. [PMID: 16610798 DOI: 10.1021/jm0504353] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In an effort to establish the structural requirements for agonism, neutral antagonism, and inverse agonism at the human histamine H(3) receptor (H(3)R) we have prepared a series of higher homologues of histamine in which the terminal nitrogen of the side chain has been either mono- or disubstituted with several aliphatic, alicyclic, and aromatic moieties or incorporated in cyclic systems. The novel ligands have been pharmacologically investigated in vitro for their affinities on the human H(3)R and H(4)R subtypes by radioligand displacement experiments and for their intrinsic H(3)R activities via a CRE-mediated beta-galactosidase reporter gene assay. Subtle changes of the substitution pattern at the side chain nitrogen alter enormously the pharmacological activity of the ligands, resulting in a series of compounds with a wide spectrum of pharmacological activities. Among the several neutral H(3)R antagonists identified within this series, compounds 2b and 2h display an H(3)R affinity in the low nanomolar concentration range (pK(i) values of 8.1 and 8.4, respectively). A very potent and selective H(3)R agonist (1l, pEC(50) = 8.9, alpha = 0.94) and a very potent, though not highly selective, H(3)R inverse agonist (2k, pIC(50) = 8.9, alpha = -0.97) have been identified as well.
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Affiliation(s)
- Marinella Govoni
- Leiden/Amsterdam Center for Drug Research, Department of Pharmacochemistry, Vrije Universiteit Amsterdam, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
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Rivara M, Zuliani V, Cocconcelli G, Morini G, Comini M, Rivara S, Mor M, Bordi F, Barocelli E, Ballabeni V, Bertoni S, Plazzi PV. Synthesis and biological evaluation of new non-imidazole H3-receptor antagonists of the 2-aminobenzimidazole series. Bioorg Med Chem 2006; 14:1413-24. [PMID: 16263297 DOI: 10.1016/j.bmc.2005.09.063] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2005] [Revised: 09/21/2005] [Accepted: 09/27/2005] [Indexed: 11/17/2022]
Abstract
A novel series of non-imidazole H(3)-receptor antagonists was developed, by chemical modification of a potent lead H(3)-antagonist composed by an imidazole ring connected through an alkyl spacer to a 2-aminobenzimidazole moiety (e.g., 2-[[3-[4(5)-imidazolyl]propyl]amino]benzimidazole), previously reported by our research group. We investigated whether the removal of the imidazole ring could allow retaining high affinity for the H(3)-receptor, thanks to the interactions undertaken by the 2-aminobenzimidazole moiety at the binding site. The imidazole ring of the lead was replaced by a basic piperidine or by a lipophilic p-chlorophenoxy substituent, modulating the spacer length from three to eight methylene groups; moreover, the substituents were moved to the 5(6) position of the benzimidazole nucleus. Within both the 2-alkylaminobenzimidazole series and the 5(6)-alkoxy-2-aminobenzimidazole one, the greatest H(3)-receptor affinity was obtained for the piperidine-substituted compounds, while the presence of the p-chlorophenoxy group resulted in a drop in affinity. The optimal chain length was different in the two series. Even if the new compounds did not reach the high receptor affinity shown by the imidazole-containing lead compound, it was possible to get good H(3)-antagonist potencies with 2-aminobenzimidazoles having a tertiary amino group at appropriate distance.
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Affiliation(s)
- Mirko Rivara
- Dipartimento Farmaceutico, Università degli Studi di Parma, Parco Area delle Scienze 27/A, Italy
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Vohora D, Pal SN, Pillai KK. Modulation of spontaneous alternation performance of mice treated with thioperamide and tacrine in a cross maze task. Fundam Clin Pharmacol 2005; 19:531-2. [PMID: 16176330 DOI: 10.1111/j.1472-8206.2005.00359.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A combination of sub-effective doses of thioperamide (7.5 mg/kg, i.p.) and tacrine (0.5 mg/kg, i.p.) enhanced performance in a spatial memory task in mice. This was shown by a significant increase in their spontaneous alternation scores in a cross maze test.
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Affiliation(s)
- Divya Vohora
- Department of Pharmacology, Faculty of Pharmacy, Hamdard University, New Delhi 110 062, India.
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35
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Baldi E, Bucherelli C, Schunack W, Cenni G, Blandina P, Passani MB. The H3 receptor protean agonist proxyfan enhances the expression of fear memory in the rat. Neuropharmacology 2005; 48:246-51. [PMID: 15695163 DOI: 10.1016/j.neuropharm.2004.09.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2004] [Revised: 09/08/2004] [Accepted: 09/16/2004] [Indexed: 10/26/2022]
Abstract
Consolidation of fear memory requires neural changes to occur in the basolateral amygdala (BLA), including modulation of histaminergic neurotransmission. We previously demonstrated that local blockade or activation of histamine H3 receptors in the BLA impaired or ameliorated, respectively, retention of fear memory. The histamine H3 receptor is a G-protein-coupled receptor (GPCR) displaying high constitutive activity that regulates histamine neurons in the brain. Proxyfan is a high-affinity histamine H3 receptor protean agonist exhibiting the full spectrum of pharmacological activities, from full agonist to full inverse agonist depending on the competition between constitutively active and quiescent H3 receptors in a given tissue or brain region. Therefore, protean agonists are powerful tools to investigate receptor conformation and may be useful in designing specific compounds selective for the various receptor conformations. In the present study we examined the effect of post-training, systemic or intra-BLA injections of proxyfan on contextual fear memory. Rats receiving intra-BLA, bilateral injections of 1.66 ng proxyfan immediately after fear conditioning showed stronger memory for the context-footshock association, as demonstrated by longer freezing assessed at retention performed 72 hr later compared to controls. Comparable results were obtained when doses as low as 0.04 mg/kg of proxyfan were injected systemically. Hence, our results suggest that proxyfan behaves as an H3 receptor agonist with a low level of constitutive activity of the H3 receptor in the rat BLA.
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Affiliation(s)
- Elisabetta Baldi
- Dipartimento di Science Fisiologiche, Università di Firenze, Viale Morgagni 63, 50134 Firenze, Italy
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36
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Walczyński K, Zuiderveld OP, Timmerman H. Non-imidazole histamine H3 ligands. Part III. New 4-n-propylpiperazines as non-imidazole histamine H3-antagonists. Eur J Med Chem 2005; 40:15-23. [PMID: 15642406 DOI: 10.1016/j.ejmech.2004.09.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2004] [Revised: 09/01/2004] [Accepted: 09/06/2004] [Indexed: 11/25/2022]
Abstract
In search for a new lead of non-imidazole histamine H3-receptor antagonists, a series of 1[(2-thiazolopyridine)-4-n-propyl]piperazines, the analogous 1-[(2-oxazolopyridine)-4-npropyl]piperazines, 1-[(2-benzothiazole)-4-n-propyl]piperazine and 1-[(2-benzooxazole)4-n-propyl]piperazine were prepared and in vitro tested as H3-receptor antagonists (the electrically evoked contraction of the guinea-pig jejunum). It appeared that by comparison of homologous pairs the thiazolo derivatives have slightly higher activity than their oxazolo analogues. The most potent compound of these series is the 1-(2-thiazolo[4,5-c]pyridine)-4-n-propylpiperazine (3c) with pA2 = 7.25 (its oxazole analogue (4g) showed pA2 = 6.9). The structure-activity relationships for compounds with various positions of the nitrogen in the benzene ring for the thiazoles compared with oxazoles are discussed.
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Affiliation(s)
- Krzysztof Walczyński
- Department of Synthesis and Technology of Drugs, Medical University Muszyńskiego, Muszyńskiego Street 1, 90-145 Łódź, Poland.
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Cowart M, Faghih R, Curtis MP, Gfesser GA, Bennani YL, Black LA, Pan L, Marsh KC, Sullivan JP, Esbenshade TA, Fox GB, Hancock AA. 4-(2-[2-(2(R)-Methylpyrrolidin-1-yl)ethyl]benzofuran-5-yl)benzonitrile and Related 2-Aminoethylbenzofuran H3 Receptor Antagonists Potently Enhance Cognition and Attention. J Med Chem 2004; 48:38-55. [PMID: 15634000 DOI: 10.1021/jm040118g] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
H(3) receptor antagonists based on a 2-aminoethylbenzofuran skeleton have been discovered, which are potent in vitro at human and rat H(3) receptors, with K(i) values of 0.1-5.8 nM. Analogues were discovered with potent (0.01-1 mg/kg) cognition and attention enhancing properties in animal models. One compound in particular, 4-(2-[2-(2(R)-methylpyrrolidin-1-yl)ethyl]benzofuran-5-yl)benzonitrile (ABT-239), combined potent and selective H(3) receptor antagonism and excellent pharmacokinetic and metabolic properties across species, with full efficacy in two behavioral models: a five-trial inhibitory avoidance acquisition model in rat pups at 0.1 mg/kg and a social recognition memory model in adult rats at 0.01 mg/kg. Furthermore, this compound did not stimulate locomotor activity and showed high selectivity for the induction of behavioral efficacy versus central nervous system based side effects. The potency and selectivity of this compound and of analogues from this class support the potential of H(3) receptor antagonists for the treatment of cognitive dysfunction.
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Affiliation(s)
- Marlon Cowart
- Department of Neuroscience Research, Abbott Laboratories, Abbott Park, Illinois 60064-6123, USA.
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Grassmann S, Apelt J, Ligneau X, Pertz HH, Arrang JM, Ganellin CR, Schwartz JC, Schunack W, Stark H. Search for Histamine H3Receptor Ligands with Combined Inhibitory Potency at HistamineN-Methyltransferase: ω-Piperidinoalkanamine Derivatives. Arch Pharm (Weinheim) 2004; 337:533-45. [PMID: 15476285 DOI: 10.1002/ardp.200400897] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
In an effort to design new hybrid compounds with dual properties, i.e. binding affinity at histamine H(3) receptors and inhibitory potency at the catabolic enzyme histamine N(tau)-methyltransferase (HMT), a novel series of 1-substituted piperidine derivatives was synthesized. This alicyclic heterocycle is structurally linked via aminoalkyl spacers of variable lengths to additional aromatic carbo- or hetero-cycles. These new hybrid drugs were pharmacologically evaluated regarding their binding affinities at recombinant human H(3) receptors, stably expressed in CHO cells, and in a functional assay for their inhibitory potencies at rat kidney HMT. All compounds investigated proved to be H(3) receptor ligands with binding affinities in the micro- to nanomolar concentration range despite significant differences in the type of the aromatic moiety introduced. The most potent compound in this series was the quinoline derivative 20 (K(i) = 5.6 nM). Likewise, all new ligands studied showed impressive HMT inhibitory activities. Here, compounds 5, 10, 14 and 18-20 exhibited submicromolar potencies (IC(50) = 0.061-0.56 microM). The aminomethylated quinoline 19 showed almost the same, well balanced nanomolar activities on both targets. In this study, new hybrid compounds with a dual mode biological action were developed. These pharmacological agents are valuable leads for further development and candidates for treatment of histamine-dependent disorders.
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Affiliation(s)
- Sven Grassmann
- Institut für Pharmazie, Institut für Pharmazie, Berlin, Germany
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39
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Bernaerts P, Lamberty Y, Tirelli E. Histamine H3 antagonist thioperamide dose-dependently enhances memory consolidation and reverses amnesia induced by dizocilpine or scopolamine in a one-trial inhibitory avoidance task in mice. Behav Brain Res 2004; 154:211-9. [PMID: 15302127 DOI: 10.1016/j.bbr.2004.02.017] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2003] [Revised: 02/12/2004] [Accepted: 02/12/2004] [Indexed: 11/25/2022]
Abstract
In the literature, there is some evidence indicating that H3 histamine receptor antagonists, in particular thioperamide, can facilitate learning and memory retrieval in laboratory rodents. The present study aimed at verifying whether this also holds for memory consolidation, a phase of memory for which there is scarcity of convincing data on the effects of H3 receptor antagonists given systemically. To that end, memory consolidation was assessed in C57BL/6J mice using the one-trial step-through inhibitory avoidance task, the compounds being injected immediately after training (foot-shock) and performance measured 24 h later. More specifically, the following effects of thioperamide (1.25-20 mg/kg) were dose-dependently analysed: (1) its potential direct effects on memory consolidation; (2) its potential reversing effects on retrograde amnesia induced by the NMDA antagonist dizocilpine (MK-801, 0.5 mg/kg) and (3) its potential reversing effects on the well-known amnesia induced by the muscarinic antagonist scopolamine (0.25 mg/kg). We found that thioperamide exerted a dose-dependent facilitative effect on memory consolidation. Furthermore, the H3 receptor antagonist reversed scopolamine- and especially dizocilpine-induced amnesia. The results strongly support the view that the brain mechanisms of memory consolidation involve a functional interaction between the NMDA and the H3 sites.
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Affiliation(s)
- Pascale Bernaerts
- Laboratoire de Neurosciences Comportementales & Psychopharmacologie Expérimentale, Université de Liège, Boulevard du Rectorat 5/Building 32, B-4000 Liège, Belgium
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40
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Browman KE, Komater VA, Curzon P, Rueter LE, Hancock AA, Decker MW, Fox GB. Enhancement of prepulse inhibition of startle in mice by the H3 receptor antagonists thioperamide and ciproxifan. Behav Brain Res 2004; 153:69-76. [PMID: 15219708 DOI: 10.1016/j.bbr.2003.11.001] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2003] [Revised: 10/28/2003] [Accepted: 11/04/2003] [Indexed: 11/28/2022]
Abstract
Histamine H3 receptor antagonists/inverse agonists have been proposed as potential therapeutic agents for the treatment of a number of neurological disorders ranging from attention deficit hyperactivity disorder and Alzheimer's disease to narcolepsy and schizophrenia. With respect to the latter, schizophrenic patients typically exhibit impaired prepulse inhibition (PPI) of startle, a reflex that can be modeled in many animal species. Certain strains of mice naturally display poor PPI and it was recently suggested that these mice might offer a new way to screen for novel antipsychotic compounds. To examine whether H3 receptor antagonists might enhance PPI in mice with naturally occurring deficits, DBA/2 and C57BL/6 were tested in a startle paradigm with three prepulse intensities: 5, 10 and 15 dB above background. Both thioperamide and ciproxifan enhanced PPI in the DBA/2 strain; thioperamide also showed a trend towards enhancing PPI in C57BL/6. Risperidone, an atypical antipsychotic, enhanced PPI in both the DBA/2 and the C57BL/6 strain. These data confirm previous reports describing a natural deficit in PPI in some mouse strains that is amenable to enhancement with known antipsychotics. Further, these data suggest that H3 receptor antagonists/inverse agonists have anti-psychotic potential for disorders such as schizophrenia.
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Affiliation(s)
- Kaitlin E Browman
- Neuroscience Research, Abbott Laboratories, AP9A, 100 Abbott Park, Abbott Park, IL 60064-6115, USA.
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41
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Witkin JM, Nelson DL. Selective histamine H3 receptor antagonists for treatment of cognitive deficiencies and other disorders of the central nervous system. Pharmacol Ther 2004; 103:1-20. [PMID: 15251226 DOI: 10.1016/j.pharmthera.2004.05.001] [Citation(s) in RCA: 113] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Evidence exists to implicate the monoamine histamine in the control of arousal and cognitive functions. Antagonists of H(3) receptors are postsynaptic and presynaptic modulators of neural transmission in a variety of neuronal circuits relevant to cognition. Accumulating neuroanatomical, neurochemical, pharmacological, and behavioral data support the idea that H(3) receptor antagonists may function to improve cognitive performances in disease states (e.g., Alzheimer's disease and mild cognitive impairment states). Thus, H(3) receptor antagonists have been shown to increase performance in attention and memory tests in nonhuman experiments and prevent the degradation in performances produced by scopolamine, MK-801, or age. In contrast, agonists of the H(3) receptor generally produce cognitive impairing effects in animal models. The role of H(3) receptors in these behavioral effects is substantiated by data indicating a central origin for their effects, the selectivity of some of the H(3) receptor antagonists studied, and the pharmacological modification of effects of H(3) receptor antagonists by selective H(3) receptor agonists. Data and issues that challenge the potential role for H(3) receptor antagonists in cognitive processes are also critically reviewed. H(3) receptor antagonists may also have therapeutic value in the management of obesity, pain, sleep disorders, schizophrenia, and attention deficit hyperactivity disorder.
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Affiliation(s)
- J M Witkin
- Neuroscience Discovery Research, Lilly Research Laboratories, Eli Lilly and Company, Lilly Corporate Center, Indianapolis, IN 46285-0510, USA.
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Bongers G, Leurs R, Robertson J, Raber J. Role of H3-receptor-mediated signaling in anxiety and cognition in wild-type and Apoe-/- mice. Neuropsychopharmacology 2004; 29:441-9. [PMID: 14628000 DOI: 10.1038/sj.npp.1300352] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Increasing evidence supports a role for histamine as a neurotransmitter and neuromodulator in emotion and cognition. The H(3) receptor was first characterized as an autoreceptor that modulates histamine release and synthesis via negative feedback. Mice deficient in apoE (Apoe(-/-)) have been used to define the role of apoE in brain function. In the present study, we investigated the possible role of histamine H(3)-receptor-mediated signaling in anxiety and cognition in mice Apoe(-/-) and wild-type mice. H(3) antagonists increased measures of anxiety in wild-type, but not Apoe(-/-), mice. In contrast, H(3) antagonists similarly impaired object recognition in wild-type and Apoe(-/-) mice. In Apoe(-/-) mice, reduced negative feedback via H(3) receptors could contribute to increased signaling of H(1) receptors. Apoe(-/-) mice showed higher sensitivity to the anxiety-reducing effects of the H(1) receptor antagonist mepyramine than wild-type mice. These effects were dissociated from effects of mepyramine on the HPA axis. Compared to saline controls, mepyramine reduced plasma ACTH and corticosterone levels in wild-type, but not Apoe(-/-), mice. These data support a role for apoE in H(3) receptor signaling. H(3) antagonists were proposed as a treatment for cognitive disorders such as Alzheimer's disease, which is associated with increased anxiety and cognitive impairments. As H(3) antagonists increase measures of anxiety and impair object recognition in wild-type mice, the use of H(3) antagonists in cognitive disorders may be counterproductive and should be carefully evaluated.
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Affiliation(s)
- Gerald Bongers
- Gladstone Institute of Neurological Disease, University of California, San Francisco, CA, USA
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Kitbunnadaj R, Zuiderveld OP, De Esch IJP, Vollinga RC, Bakker R, Lutz M, Spek AL, Cavoy E, Deltent MF, Menge WMPB, Timmerman H, Leurs R. Synthesis and structure-activity relationships of conformationally constrained histamine H(3) receptor agonists. J Med Chem 2004; 46:5445-57. [PMID: 14640553 DOI: 10.1021/jm030905y] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Immepip, a conformationally constrained analogue of the histamine congener imbutamine, shows high affinity and functional activity on the human H(3) receptor. Using histamine and its homologues as prototypes, other rigid analogues containing either a piperidine or pyrrolidine ring in the side chain were synthesized and tested for their activities at the human H(3) receptor and the closely related H(4) receptor. In the series of piperidine containing analogues, immepip was found to be the most potent H(3) receptor agonist, whereas its propylene analogue 13a was identified as a high-affinity neutral antagonist for the human H(3) receptor. Moreover, replacement of the piperidine ring of immepip by a pyrrolidine ring led to a pair of enantiomers that show a distinct stereoselectivity at the human H(3) and H(4) receptor.
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Affiliation(s)
- Ruengwit Kitbunnadaj
- Leiden/Amsterdam Center of Drug Research (LACDR), Department of Pharmacochemistry, Faculty of Chemistry, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands
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Blandina P, Efoudebe M, Cenni G, Mannaioni P, Passani MB. Acetylcholine, Histamine, and Cognition: Two Sides of the Same Coin. Learn Mem 2004; 11:1-8. [PMID: 14747511 DOI: 10.1101/lm.68004] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Patrizio Blandina
- Dipartimento di Farmacologia Preclinica e Clinica, V.le G. Pieraccini 6, Universitá di Firenze, 50139 Firenze, Italy.
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45
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Fox GB, Pan JB, Radek RJ, Lewis AM, Bitner RS, Esbenshade TA, Faghih R, Bennani YL, Williams M, Yao BB, Decker MW, Hancock AA. Two novel and selective nonimidazole H3 receptor antagonists A-304121 and A-317920: II. In vivo behavioral and neurophysiological characterization. J Pharmacol Exp Ther 2003; 305:897-908. [PMID: 12606600 DOI: 10.1124/jpet.102.047241] [Citation(s) in RCA: 92] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Pharmacological blockade of central histamine H3 receptors (H3Rs) enhances cognition in rodents and offers promise for the clinical treatment of neurological disorders. However, many previously characterized H3R antagonists are either not selective for H3Rs or have potentially significant tolerability issues. Here, we present in vivo behavioral and neurophysiological data for two novel and selective H3R antagonists with improved safety indices. Functional blockade of central H3Rs was first demonstrated for A-304121 [(4-(3-(4-((2R)-2-aminopropanoyl)-1-piperazinyl)propoxy)phenyl)cyclopropylmethanone] (1 mg/kg) and A-317920 [N-((1R)-2-(4-(3-(4-(cyclopropylcarbonyl)phenoxy)propyl)-1-piperazinyl)-1-methyl-2-oxo-ethyl)-2-furamide] (0.45 mg/kg) by significantly attenuating an acute dipsogenia response to the selective H3R agonist (R)-alpha-methylhistamine [(R)-alpha-MeHA]. Cognitive performance was improved in a five-trial rat pup avoidance test following administration of A-304121 (10 mg/kg) or A-317920 (3 mg/kg), with efficacy comparable with previously published observations for reference H3R antagonists thioperamide (10 mg/kg), ciproxifan (3 mg/kg), and GT-2331 [(1R,2R)-4-(2-(5,5-dimethylhex-1-ynyl)cyclopropyl)imidazole] (1 mg/kg). Social memory was also significantly enhanced in the adult rat with A-304121 (3, 10 mg/kg) and A-317920 (1, 3 mg/kg) at doses that produced no significant change in electroencephalogram slow-wave amplitude activity. Relative therapeutic indices (TIs) of 30 and 42 were estimated for A-304121 and A-317920, respectively, by comparing doses producing adverse effects in general observation studies with potency in inhibitory avoidance, which were superior to TIs of 8, 10, and 18 observed for the reference antagonists thioperamide, ciproxifan, and GT-2331, respectively. A-304121 and A-317920 represent a series of novel, H3R-selective piperazine amides that enhance cognition in vivo, which could offer advantages over existing H3R antagonists or cognition-enhancing agents.
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Affiliation(s)
- Gerard B Fox
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, AP9A, R4N5, 100 Abbott Park Road, Abbott Park, IL 60064-6115, USA.
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46
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Komater VA, Browman KE, Curzon P, Hancock AA, Decker MW, Fox GB. H3 receptor blockade by thioperamide enhances cognition in rats without inducing locomotor sensitization. Psychopharmacology (Berl) 2003; 167:363-72. [PMID: 12682709 DOI: 10.1007/s00213-003-1431-0] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/20/2002] [Accepted: 02/11/2003] [Indexed: 11/29/2022]
Abstract
RATIONALE Attention deficit hyperactivity disorder (ADHD) is currently treated with psychomotor stimulants, including methylphenidate and amphetamine. Several adverse effects are associated with these drugs, however, such as agitation and abuse. H(3) receptor antagonists are under clinical investigation for ADHD. OBJECTIVES To investigate the potential of thioperamide, a prototypical H(3) receptor antagonist, to enhance learning and attention while inducing no effects on locomotor stimulation and sensitization, or alterations in ACTH levels. METHODS Thioperamide (1, 3, 10, 30 mg/kg) was administered prior to testing in a multi-trial, inhibitory avoidance response in rat pups (five trials separated by 1 min) to evaluate attention/cognition. Locomotor sensitization and cross-sensitization was assessed following administration of methylphenidate (3 mg/kg), cocaine (10 mg/kg), or thioperamide (1, 3, 10 mg/kg). RESULTS Thioperamide significantly enhanced performance of the five-trial inhibitory avoidance response with efficacy similar to that previously reported for methylphenidate. Administration of amphetamine, methylphenidate and cocaine produced significant locomotor sensitization, however. In contrast, thioperamide did not induce locomotor stimulation or sensitization, nor did it cross-sensitize to the stimulant effects of amphetamine or cocaine. The repeated administration of methylphenidate significantly elevated ACTH levels, while thioperamide did not affect this neuroendocrine endpoint. CONCLUSIONS H(3) receptor blockade may offer a safer alternative to psychomotor stimulants for the treatment of ADHD.
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Affiliation(s)
- Victoria A Komater
- Neuroscience Research, Abbott Laboratories, AP9A, D4N5, Abbott Park, IL 60064, USA
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47
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Grassmann S, Apelt J, Sippl W, Ligneau X, Pertz HH, Zhao YH, Arrang JM, Ganellin CR, Schwartz JC, Schunack W, Stark H. Imidazole derivatives as a novel class of hybrid compounds with inhibitory histamine N-methyltransferase potencies and histamine hH3 receptor affinities. Bioorg Med Chem 2003; 11:2163-74. [PMID: 12713826 DOI: 10.1016/s0968-0896(03)00120-2] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this study, a novel series of imidazole-containing compounds with dual properties, that is, inhibitory potency at the enzyme histamine N(tau)-methyltransferase (HMT) and antagonist potency at histamine H(3) receptors was designed and synthesized. Pharmacologically, these new hybrid drugs were evaluated in functional assays for their inhibitory potencies at rat kidney HMT and for their antagonist activities on synaptosomes of rat cerebral cortex. For selected compounds, binding affinities at recombinant human histamine H(3) receptors were determined. The first compounds (1-10) of the series proved to be H(3) receptor ligands of high potency at rat synaptosomes or of high binding affinity at human H(3) receptors, respectively, but of only moderate activity as inhibitors of rat kidney HMT. In contrast, aminoquinoline- or tetrahydroacridine-containing derivatives 11-17 also displayed HMT inhibitory potency in the nanomolar concentration range. Preliminary data from molecular modeling investigations showed that the imidazole derivative 15 and the HMT inhibitor quinacrine possess identical binding areas. The most interesting compound (14) is simultaneously a highly potent H(3) receptor ligand (K(i)=4.1nM) and a highly potent HMT inhibitor (IC(50)=24nM), which makes this derivative a valuable pharmacological tool for further development.
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Affiliation(s)
- Sven Grassmann
- Institut für Pharmazie, Freie Universität Berlin, Königin-Luise-Strasse 2+4, 14195 Berlin, Germany
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48
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Meier G, Ligneau X, Pertz HH, Ganellin CR, Schwartz JC, Schunack W, Stark H. Piperidino-hydrocarbon compounds as novel non-imidazole histamine H(3)-receptor antagonists. Bioorg Med Chem 2002; 10:2535-42. [PMID: 12057642 DOI: 10.1016/s0968-0896(02)00115-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
In search for novel non-imidazole histamine H(3)-receptor antagonists, piperidino-hydrocarbon compounds were synthesized using the known non-imidazole histamine H(3)-receptor antagonist FUB 637 (3-phenylpropyl 3-piperidinopropyl ether) as lead structure. Piperidino-alkyl derivatives containing highly flexible side chains (2, 4-7) were prepared via N-alkylation. Compounds containing unsaturated alkyl groups were synthesized in order to investigate the impact of rigidifying the side chain (8-16). Terminal alkynes were prepared by alkylation of lithium acetylide-ethylenediamine complex, disubstituted alkynes were synthesized by alkylation of the appropriate acetylene in the presence of n-butyllithium-N,N,N',N'-tetramethylene-ethylene-diamine complex. The novel compounds were investigated in an in vitro functional assay on the guinea-pig ileum, in which N-(7-phenylhept-3-ynyl)piperidine (14) proved to be of good potency in this class (pA(2)=7.21). In an in vivo assay the compounds were additionally screened for their abilities to influence central H(3)-histaminergic neuron activity in mice with regard to their oral availabilities and distribution properties. In this screening, N-pent-4-ynylpiperidine (9) and N-hex-5-ynylpiperidine (10) proved to be highly potent and orally available histamine H(3)-receptor antagonists. The ED(50) values for 9 and 10 were 1.3 and 1.4mg/kg po, respectively, which is in the potency range of the reference antagonist thioperamide.
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Affiliation(s)
- Galina Meier
- Institut für Pharmazie, Freie Universität Berlin, Königin-Luise-Strasse 2+4, 14195 Berlin, Germany
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49
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Toyota H, Dugovic C, Koehl M, Laposky AD, Weber C, Ngo K, Wu Y, Lee DH, Yanai K, Sakurai E, Watanabe T, Liu C, Chen J, Barbier AJ, Turek FW, Fung-Leung WP, Lovenberg TW. Behavioral characterization of mice lacking histamine H(3) receptors. Mol Pharmacol 2002; 62:389-97. [PMID: 12130692 DOI: 10.1124/mol.62.2.389] [Citation(s) in RCA: 163] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Brain histamine H(3) receptors are predominantly presynaptic and serve an important autoregulatory function for the release of histamine and other neurotransmitters. They have been implicated in a variety of brain functions, including arousal, locomotor activity, thermoregulation, food intake, and memory. The recent cloning of the H(3) receptor in our laboratory has made it possible to create a transgenic line of mice devoid of H(3) receptors. This paper provides the first description of the H(3) receptor-deficient mouse (H(3)(-/-)), including molecular and pharmacologic verification of the receptor deletion as well as phenotypic screens. The H(3)(-/-) mice showed a decrease in overall locomotion, wheel-running behavior, and body temperature during the dark phase but maintained normal circadian rhythmicity. H(3)(-/-) mice were insensitive to the wake-promoting effects of the H(3) receptor antagonist thioperamide. We also observed a slightly decreased stereotypic response to the dopamine releaser, methamphetamine, and an insensitivity to the amnesic effects of the cholinergic receptor antagonist, scopolamine. These data indicate that the H(3) receptor-deficient mouse represents a valuable model for studying histaminergic regulation of a variety of behaviors and neurotransmitter systems, including dopamine and acetylcholine.
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Affiliation(s)
- Hiroshi Toyota
- Johnson & Johnson Pharmaceutical Research and Development, San Diego, California 92121, USA
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50
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Fox GB, Pan JB, Esbenshade TA, Bitner RS, Nikkel AL, Miller T, Kang CH, Bennani YL, Black LA, Faghih R, Hancock AA, Decker MW. Differential in vivo effects of H3 receptor ligands in a new mouse dipsogenia model. Pharmacol Biochem Behav 2002; 72:741-50. [PMID: 12175472 DOI: 10.1016/s0091-3057(02)00745-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The selective H(3) receptor agonist (R)-alpha-methylhistamine [(R)-alpha-MeHA] stimulates drinking in the adult rat. In the present study, we investigated the role of the H(3) receptor in mediating this behavior in a new dipsogenia model using the CD-1 mouse. In addition, the putative inverse agonists ciproxifan, thioperamide and clobenpropit; the reported antagonist (1R,2R)-4-[2-(5,5-dimethylhex-1-ynyl)cyclopropyl]imidazole (GT-2331); and the putative neutral antagonist/weak partial agonist proxyfan were evaluated for possible differences in pharmacological activity in this new model. Water intake increased over baseline in a dose-related manner following intraperitoneal administration of 80, 160 or 240 micromol/kg (R)-alpha-MeHA, but this effect was dependent on age (P30<P60<P80=P120). [3H]-N-alpha-methylhistamine binding studies showed no change in H(3) receptor density for the whole mouse brain at these ages. All subsequent studies employed P80 mice dosed with 240 micromol/kg (R)-alpha-MeHA. Ciproxifan (0.001-30 micromol/kg), thioperamide (0.01-10 micromol/kg), clobenpropit (0.1-30 micromol/kg) and GT-2331 (0.03-10 micromol/kg) attenuated drinking dose-dependently, blocking the response completely at the highest doses in each case. In contrast, proxyfan (0.001-10 micromol/kg) only partially attenuated drinking elicited by (R)-alpha-MeHA: coadministration of proxyfan and ciproxifan resulted in an attenuation of ciproxifan's effects. This new dipsogenia model provides the first in vivo behavioral evidence for possible pharmacological differences between three putative H(3) receptor inverse agonists, GT-2331 and proxyfan.
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Affiliation(s)
- Gerard B Fox
- Neuroscience Research, Global Pharmaceutical Research and Development, Abbott Laboratories, AP9A, R4N5, Abbott Park, IL 60064-6115, USA.
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