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Peng JY, Qi ZX, Yan Q, Fan XJ, Shen KL, Huang HW, Lu JH, Wang XQ, Fang XX, Mao L, Ni J, Chen L, Zhuang QX. Ameliorating parkinsonian motor dysfunction by targeting histamine receptors in entopeduncular nucleus-thalamus circuitry. Proc Natl Acad Sci U S A 2023; 120:e2216247120. [PMID: 37068253 PMCID: PMC10151461 DOI: 10.1073/pnas.2216247120] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Accepted: 03/07/2023] [Indexed: 04/19/2023] Open
Abstract
In Parkinson's disease (PD), reduced dopamine levels in the basal ganglia have been associated with altered neuronal firing and motor dysfunction. It remains unclear whether the altered firing rate or pattern of basal ganglia neurons leads to parkinsonism-associated motor dysfunction. In the present study, we show that increased histaminergic innervation of the entopeduncular nucleus (EPN) in the mouse model of PD leads to activation of EPN parvalbumin (PV) neurons projecting to the thalamic motor nucleus via hyperpolarization-activated cyclic nucleotide-gated (HCN) channels coupled to postsynaptic H2R. Simultaneously, this effect is negatively regulated by presynaptic H3R activation in subthalamic nucleus (STN) glutamatergic neurons projecting to the EPN. Notably, the activation of both types of receptors ameliorates parkinsonism-associated motor dysfunction. Pharmacological activation of H2R or genetic upregulation of HCN2 in EPNPV neurons, which reduce neuronal burst firing, ameliorates parkinsonism-associated motor dysfunction independent of changes in the neuronal firing rate. In addition, optogenetic inhibition of EPNPV neurons and pharmacological activation or genetic upregulation of H3R in EPN-projecting STNGlu neurons ameliorate parkinsonism-associated motor dysfunction by reducing the firing rate rather than altering the firing pattern of EPNPV neurons. Thus, although a reduced firing rate and more regular firing pattern of EPNPV neurons correlate with amelioration in parkinsonism-associated motor dysfunction, the firing pattern appears to be more critical in this context. These results also confirm that targeting H2R and its downstream HCN2 channel in EPNPV neurons and H3R in EPN-projecting STNGlu neurons may represent potential therapeutic strategies for the clinical treatment of parkinsonism-associated motor dysfunction.
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Affiliation(s)
- Jian-Ya Peng
- Department of Physiology, School of Medicine, Nantong University, Nantong, Jiangsu226001, China
| | - Zeng-Xin Qi
- Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai200030, China
- National Center for Neurological Disorders, Shanghai200030, China
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai200030, China
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai200030, China
| | - Qi Yan
- Department of Physiology, School of Medicine, Nantong University, Nantong, Jiangsu226001, China
| | - Xiu-Juan Fan
- Department of Physiology, School of Medicine, Nantong University, Nantong, Jiangsu226001, China
| | - Kang-Li Shen
- Department of Physiology, School of Medicine, Nantong University, Nantong, Jiangsu226001, China
| | - Hui-Wei Huang
- Department of Physiology, School of Medicine, Nantong University, Nantong, Jiangsu226001, China
| | - Jian-Hua Lu
- Department of Physiology, School of Medicine, Nantong University, Nantong, Jiangsu226001, China
| | - Xiao-Qin Wang
- Department of Physiology, School of Medicine, Nantong University, Nantong, Jiangsu226001, China
| | - Xiao-Xia Fang
- Department of Physiology, School of Medicine, Nantong University, Nantong, Jiangsu226001, China
| | - Liming Mao
- Department of Immunology, School of Medicine, Nantong University, Nantong, Jiangsu226001, China
- Basic Medical Research Center, School of Medicine, Nantong University, Nantong226019, China
| | - Jianguang Ni
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai200030, China
| | - Liang Chen
- Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai200030, China
- National Center for Neurological Disorders, Shanghai200030, China
- Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai200030, China
- State Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai200030, China
| | - Qian-Xing Zhuang
- Department of Physiology, School of Medicine, Nantong University, Nantong, Jiangsu226001, China
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2
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Buzoianu AD, Sharma A, Muresanu DF, Feng L, Huang H, Chen L, Tian ZR, Nozari A, Lafuente JV, Wiklund L, Sharma HS. Nanodelivery of Histamine H3/H4 Receptor Modulators BF-2649 and Clobenpropit with Antibodies to Amyloid Beta Peptide in Combination with Alpha Synuclein Reduces Brain Pathology in Parkinson's Disease. ADVANCES IN NEUROBIOLOGY 2023; 32:55-96. [PMID: 37480459 DOI: 10.1007/978-3-031-32997-5_2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/24/2023]
Abstract
Parkinson's disease (PD) in military personnel engaged in combat operations is likely to develop in their later lives. In order to enhance the quality of lives of PD patients, exploration of novel therapy based on new research strategies is highly warranted. The hallmarks of PD include increased alpha synuclein (ASNC) and phosphorylated tau (p-tau) in the cerebrospinal fluid (CSF) leading to brain pathology. In addition, there are evidences showing increased histaminergic nerve fibers in substantia niagra pars compacta (SNpc), striatum (STr), and caudate putamen (CP) associated with upregulation of histamine H3 receptors and downregulation of H4 receptors in human brain. Previous studies from our group showed that modulation of potent histaminergic H3 receptor inverse agonist BF-2549 or clobenpropit (CLBPT) partial histamine H4 agonist with H3 receptor antagonist induces neuroprotection in PD brain pathology. Recent studies show that PD also enhances amyloid beta peptide (AβP) depositions in brain. Keeping these views in consideration in this review, nanowired delivery of monoclonal antibodies to AβP together with ASNC and H3/H4 modulator drugs on PD brain pathology is discussed based on our own observations. Our investigation shows that TiO2 nanowired BF-2649 (1 mg/kg, i.p.) or CLBPT (1 mg/kg, i.p.) once daily for 1 week together with nanowired delivery of monoclonal antibodies (mAb) to AβP and ASNC induced superior neuroprotection in PD-induced brain pathology. These observations are the first to show the modulation of histaminergic receptors together with antibodies to AβP and ASNC induces superior neuroprotection in PD. These observations open new avenues for the development of novel drug therapies for clinical strategies in PD.
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Affiliation(s)
- Anca D Buzoianu
- Department of Clinical Pharmacology and Toxicology, "Iuliu Hatieganu" University of Medicine and Pharmacy, Cluj-Napoca, Romania
| | - Aruna Sharma
- International Experimental Central Nervous System Injury & Repair (IECNSIR), Department of Surgical Sciences, Anesthesiology & Intensive Care Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden
| | - Dafin F Muresanu
- Department of Clinical Neurosciences, University of Medicine & Pharmacy, Cluj-Napoca, Romania
- "RoNeuro" Institute for Neurological Research and Diagnostic, Cluj-Napoca, Romania
| | - Lianyuan Feng
- Department of Neurology, Bethune International Peace Hospital, Zhongshan, Hebei Province, China
| | - Hongyun Huang
- Beijing Hongtianji Neuroscience Academy, Beijing, China
| | - Lin Chen
- Department of Neurosurgery, Dongzhimen Hospital, Beijing University of Traditional Chinese Medicine, Beijing, China
| | - Z Ryan Tian
- Department of Chemistry & Biochemistry, University of Arkansas, Fayetteville, AR, USA
| | - Ala Nozari
- Anesthesiology & Intensive Care, Chobanian & Avedisian School of Medicine, Boston University, Boston, MA, USA
| | - José Vicente Lafuente
- LaNCE, Department of Neuroscience, University of the Basque Country (UPV/EHU), Leioa, Bizkaia, Spain
| | - Lars Wiklund
- International Experimental Central Nervous System Injury & Repair (IECNSIR), Department of Surgical Sciences, Anesthesiology & Intensive Care Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden
| | - Hari Shanker Sharma
- International Experimental Central Nervous System Injury & Repair (IECNSIR), Department of Surgical Sciences, Anesthesiology & Intensive Care Medicine, Uppsala University Hospital, Uppsala University, Uppsala, Sweden.
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Qi ZX, Shen KL, Peng JY, Fan XJ, Huang HW, Jiang JL, Lu JH, Wang XQ, Fang XX, Chen L, Zhuang QX. Histamine bidirectionally regulates the intrinsic excitability of parvalbumin-positive neurons in the lateral globus pallidus and promotes motor behaviour. Br J Pharmacol 2022; 180:1379-1407. [PMID: 36512485 DOI: 10.1111/bph.16010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2022] [Revised: 12/06/2022] [Accepted: 12/08/2022] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND AND PURPOSE Parvalbumin (PV)-positive neurons are a type of neuron in the lateral globus pallidus (LGP) which plays an important role in motor control. The present study investigated the effect of histamine on LGPPV neurons and motor behaviour. EXPERIMENTAL APPROACH Histamine levels in LGP as well as its histaminergic innervation were determined through brain stimulation, microdialysis, anterograde tracing and immunostaining. Mechanisms of histamine action were detected by immunostaining, single-cell qPCR, whole-cell patch-clamp recording, optogenetic stimulation and CRISPR/Cas9 gene-editing techniques. The effect of histamine on motor behaviour was detected by animal behavioural tests. KEY RESULTS A direct histaminergic innervation in LGP from the tuberomammillary nucleus (TMN) and a histamine-induced increase in the intrinsic excitability of LGPPV neurons were determined by pharmacological blockade or by genetic knockout of the histamine H1 receptor (H1 R)-coupled TWIK-related potassium channel-1 (TREK-1) and the small-conductance calcium-activated potassium channel (SK3), as well as by activation or overexpression of the histamine H2 receptor (H2 R)-coupled hyperpolarization-activated cyclic nucleotide-gated channel (HCN2). Histamine negatively regulated the STN → LGPGlu transmission in LGPPV neurons via the histamine H3 receptor (H3 R), whereas blockage or knockout of H3 R increased the intrinsic excitability of LGPPV neurons. CONCLUSIONS AND IMPLICATIONS Our results indicated that the endogenous histaminergic innervation in the LGP can bidirectionally promote motor control by increasing the intrinsic excitability of LGPPV neurons through postsynaptic H1 R and H2 R, albeit its action was negatively regulated by the presynaptic H3 R, thereby suggesting possible role of histamine in motor deficits manifested in Parkinson's disease (PD).
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Affiliation(s)
- Zeng-Xin Qi
- Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.,National Center for Neurological Disorders, Shanghai, China.,Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China
| | - Kang-Li Shen
- Department of Physiology, School of Medicine, and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China
| | - Jian-Ya Peng
- Department of Physiology, School of Medicine, and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China
| | - Xiu-Juan Fan
- Department of Physiology, School of Medicine, and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China
| | - Hui-Wei Huang
- Department of Physiology, School of Medicine, and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China
| | - Jian-Lan Jiang
- Department of Physiology, School of Medicine, and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China
| | - Jian-Hua Lu
- Department of Physiology, School of Medicine, and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China
| | - Xiao-Qin Wang
- Department of Physiology, School of Medicine, and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China
| | - Xiao-Xia Fang
- Department of Physiology, School of Medicine, and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China
| | - Liang Chen
- Department of Neurosurgery, Huashan Hospital, Shanghai Medical College, Fudan University, Shanghai, China.,National Center for Neurological Disorders, Shanghai, China.,Shanghai Key Laboratory of Brain Function Restoration and Neural Regeneration, Shanghai, China.,State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, School of Basic Medical Sciences and Institutes of Brain Science, Fudan University, Shanghai, China
| | - Qian-Xing Zhuang
- Department of Physiology, School of Medicine, and Co-innovation Center of Neuroregeneration, Nantong University, Nantong, Jiangsu, China
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4
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Ghazanfari N, van Waarde A, Doorduin J, Sijbesma JWA, Kominia M, Koelewijn M, Attia K, Vállez-García D, Willemsen ATM, Heeres A, Dierckx RAJO, Visser TJ, de Vries EFJ, Elsinga PH. Binding of the Dual-Action Anti-Parkinsonian Drug AG-0029 to Dopamine D 2 and Histamine H 3 Receptors: A PET Study in Healthy Rats. Mol Pharm 2022; 19:2287-2298. [PMID: 35732005 PMCID: PMC9257755 DOI: 10.1021/acs.molpharmaceut.2c00121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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Introduction: Parkinson’s disease (PD) is a
neurodegenerative disorder characterized by motor dysfunction and
a diverse range of nonmotor symptoms. Functional relationships between
the dopaminergic and histaminergic systems suggest that dual-action
pharmaceuticals like AG-0029 (D2/D3 agonist/H3 antagonist) could ameliorate both the motor and cognitive
symptoms of PD. The current study aimed to demonstrate the interaction
of AG-0029 with its intended targets in the mammalian brain using
positron emission tomography (PET). Methods: Healthy
male Wistar rats were scanned with a small-animal PET camera, using
either the dopamine D2/D3 receptor ligand [11C]raclopride or the histamine H3 receptor ligand
[11C]GSK-189254, before and after treatment with an intravenous,
acute, single dose of AG-0029. Dynamic [11C]raclopride
PET data (60 min duration) were analyzed using the simplified reference
tissue model 2 (SRTM2) with cerebellum as reference tissue and the
nondisplaceable binding potential as the outcome parameter. Data from
dynamic [11C]GSK-189254 scans (60 min duration) with arterial
blood sampling were analyzed using Logan graphical analysis with the
volume of distribution (VT) as the outcome
parameter. Receptor occupancy was estimated using a Lassen plot. Results: Dopamine D2/3 receptor occupancies in
the striatum were 22.6 ± 18.0 and 84.0 ± 3.5% (mean ±
SD) after administration of 0.1 and 1 mg/kg AG-0029, respectively.
In several brain regions, the VT values
of [11C]GSK-189254 were significantly reduced after pretreatment
of rats with 1 or 10 mg/kg AG-0029. The H3 receptor occupancies
were 11.9 ± 8.5 and 40.3 ± 11.3% for the 1 and 10 mg/kg
doses of AG-0029, respectively. Conclusions: Target engagement
of AG-0029 as an agonist at dopamine D2/D3 receptors
and an antagonist at histamine H3 receptors could be demonstrated
in the rat brain with [11C]raclopride and [11C]GSK-189254 PET, respectively. The measured occupancy values reflect
the previously reported high (subnanomolar) affinity of AG-0029 to
D2/D3 and moderate (submicromolar) affinity
to H3 receptors.
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Affiliation(s)
- Nafiseh Ghazanfari
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - Aren van Waarde
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - Janine Doorduin
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - Jürgen W A Sijbesma
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - Maria Kominia
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | | | - Khaled Attia
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - David Vállez-García
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - Antoon T M Willemsen
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - André Heeres
- Symeres B.V., Kadijk 3, 9747 AT Groningen, The Netherlands
| | - Rudi A J O Dierckx
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - Ton J Visser
- Symeres B.V., Kadijk 3, 9747 AT Groningen, The Netherlands
| | - Erik F J de Vries
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
| | - Philip H Elsinga
- Department of Nuclear Medicine and Molecular Imaging, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9713 GZ Groningen, The Netherlands
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5
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Kitanaka N, Hall FS, Tanaka KI, Tomita K, Igarashi K, Nishiyama N, Sato T, Uhl GR, Kitanaka J. Are Histamine H 3 Antagonists the Definitive Treatment for Acute Methamphetamine Intoxication? Curr Drug Res Rev 2022; 14:162-170. [PMID: 35431009 DOI: 10.2174/2589977514666220414122847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Revised: 12/21/2021] [Accepted: 12/31/2021] [Indexed: 06/14/2023]
Abstract
BACKGROUND Methamphetamine (METH) is classified as a Schedule II stimulant drug under the United Nations Convention on Psychotropic Substances of 1971. METH and other amphetamine analogues (AMPHs) are powerful addictive drugs. Treatments are needed to treat the symptoms of METH addiction, chronic METH use, and acute METH overdose. No effective treatment for METH abuse has been established because alterations of brain functions under the excessive intake of abused drug intake are largely irreversible due in part to brain damage that occurs in the course of chronic METH use. OBJECTIVE Modulation of brain histamine neurotransmission is involved in several neuropsychiatric disorders, including substance use disorders. This review discusses the possible mechanisms underlying the therapeutic effects of histamine H3 receptor antagonists on symptoms of methamphetamine abuse. CONCLUSION Treatment of mice with centrally acting histamine H3 receptor antagonists increases hypothalamic histamine contents and reduces high-dose METH effects while potentiating lowdose effects via histamine H3 receptors that bind released histamine. On the basis of experimental evidence, it is hypothesized that histamine H3 receptors may be an effective target for the treatment METH use disorder or other adverse effects of chronic METH use.
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Affiliation(s)
- Nobue Kitanaka
- Department of Pharmacology, Hyogo College of Medicine, Hyogo 663-8501, Japan
| | - F Scott Hall
- Department of Pharmacology and Experimental Therapeutics, College of Pharmacy and Pharmaceutical Sciences, University of Toledo, Toledo, Ohio 43614, USA
| | - Koh-Ichi Tanaka
- Division of Pharmacology, Department of Pharmacy, School of Pharmacy, Hyogo University of Health Sciences, Hyogo 650-8530, Japan
| | - Kazuo Tomita
- Department of Applied Pharmacology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan
| | - Kento Igarashi
- Neurology and Research Services, New Mexico VA Healthcare System, Albuquerque, New Mexico 87108, USA
| | - Nobuyoshi Nishiyama
- Division of Pharmacology, Department of Pharmacy, School of Pharmacy, Hyogo University of Health Sciences, Hyogo 650-8530, Japan
| | - Tomoaki Sato
- Department of Applied Pharmacology, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima 890-8544, Japan
| | - George R Uhl
- Neurology and Research Services, New Mexico VA Healthcare System, Albuquerque, New Mexico 87108, USA
- Departments of Neurology, Neuroscience, Molecular Genetics and Microbiology, University of New Mexico, Albuquerque, New Mexico 87131, USA
| | - Junichi Kitanaka
- Department of Pharmacology, Hyogo College of Medicine, Hyogo 663-8501, Japan
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Morales-Figueroa GE, Rivera-Ramírez N, González-Pantoja R, Escamilla-Sánchez J, García-Hernández U, Galván EJ, Arias-Montaño JA. Adenosine A 2A and histamine H 3 receptors interact at the cAMP/PKA pathway to modulate depolarization-evoked [ 3H]-GABA release from rat striato-pallidal terminals. Purinergic Signal 2018; 15:85-93. [PMID: 30565027 DOI: 10.1007/s11302-018-9638-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 11/20/2018] [Indexed: 02/06/2023] Open
Abstract
We previously reported that the activation of histamine H3 receptors (H3Rs) selectively counteracts the facilitatory action of adenosine A2A receptors (A2ARs) on GABA release from rat globus pallidus (GP) isolated nerve terminals (synaptosomes). In this work, we examined the mechanisms likely to underlie this functional interaction. Three possibilities were explored: (a) changes in receptor affinity for agonists induced by physical A2AR/H3R interaction, (b) opposite actions of A2ARs and H3Rs on depolarization-induced Ca2+ entry, and (c) an A2AR/H3R interaction at the level of adenosine 3',5'-cyclic monophosphate (cAMP) formation. In GP synaptosomal membranes, H3R activation with immepip reduced A2AR affinity for the agonist 2-p-(2-carboxyethyl)phenethylamino-5'-N-ethylcarboxamidoadenosine hydrochloride hydrate (CGS-21680) (Ki control 4.53 nM; + immepip 9.32 nM), whereas A2AR activation increased H3R affinity for immepip (Ki control 0.63 nM; + CGS-21680 0.26 nM). Neither A2AR activation nor H3R stimulation modified calcium entry through voltage-gated calcium channels in GP synaptosomes, as evaluated by microfluorometry. A2AR-mediated facilitation of depolarization-evoked [2,3-3H]-γ-aminobutyric acid ([3H]-GABA) release from GP synaptosomes (130.4 ± 3.6% of control values) was prevented by the PKA inhibitor H-89 and mimicked by the adenylyl cyclase activator forskolin or by 8-Bromo-cAMP, a membrane permeant cAMP analogue (169.5 ± 17.3 and 149.5 ± 14.5% of controls). H3R activation failed to reduce the facilitation of [3H]-GABA release induced by 8-Bromo-cAMP. In GP slices, A2AR activation stimulated cAMP accumulation (290% of basal) and this effect was reduced (- 75%) by H3R activation. These results indicate that in striato-pallidal nerve terminals, A2ARs and H3Rs interact at the level of cAMP formation to modulate PKA activity and thus GABA release.
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Affiliation(s)
- Guadalupe-Elide Morales-Figueroa
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, AV. IPN 2508, Ciudad de México, México
| | - Nayeli Rivera-Ramírez
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, AV. IPN 2508, Ciudad de México, México
| | - Raúl González-Pantoja
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, AV. IPN 2508, Ciudad de México, México
| | - Juan Escamilla-Sánchez
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, AV. IPN 2508, Ciudad de México, México
| | - Ubaldo García-Hernández
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, AV. IPN 2508, Ciudad de México, México
| | - Emilio J Galván
- Departamento de Farmacobiología, Centro de Investigación y de Estudios Avanzados del IPN, AV. IPN 2508, 07360, MÉXICO, México
| | - José-Antonio Arias-Montaño
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, AV. IPN 2508, Ciudad de México, México.
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7
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Liu Y, Zeng H, Pediani JD, Ward RJ, Chen LY, Wu N, Ma L, Tang M, Yang Y, An S, Guo XX, Hao Q, Xu TR. Visualization of the activation of the histamine H3 receptor (H3R) using novel fluorescence resonance energy transfer biosensors and their potential application to the study of H3R pharmacology. FEBS J 2018; 285:2319-2336. [PMID: 29701013 DOI: 10.1111/febs.14484] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 03/24/2018] [Accepted: 04/20/2018] [Indexed: 12/14/2022]
Abstract
Activation of the histamine-3 receptor (H3R) is involved in memory processes and cognitive action, while blocking H3R activation can slow the progression of neurological disorders, such as Alzheimer's disease, schizophrenia and narcolepsy. To date, however, no direct way to examine the activation of H3R has been utilized. Here, we describe a novel biosensor that can visualize the activation of H3R through an intramolecular fluorescence resonance energy transfer (FRET) signal. To achieve this, we constructed an intramolecular H3R FRET sensor with cyan fluorescent protein (CFP) attached at the C terminus and yellow fluorescent protein (YFP) inserted into the third intracellular loop. The sensor was found to internalize normally on agonist treatment. We measured FRET signals between the donor CFP and the acceptor YFP in living cells in real time, the results of which indicated that H3R agonist treatment (imetit or histamine) increases the FRET signal in a time- and concentration-dependent manner with Kon and Koff values consistent with published data and which maybe correlated with decreasing cAMP levels and the promotion of ERK1/2 phosphorylation. The FRET signal was inhibited by H3R antagonists, and the introduction of mutations at F419A, F423A, L426A and L427A, once again, the promotion of ERK1/2 phosphorylation, was diminished. Thus, we have built a H3R biosensor which can visualize the activation of receptor through real-time structure changes and which can obtain pharmacological kinetic data at the same time. The FRET signals may allow the sensor to become a useful tool for screening compounds and optimizing useful ligands.
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Affiliation(s)
- Ying Liu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Hong Zeng
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - John D Pediani
- Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK
| | - Richard J Ward
- Molecular Pharmacology Group, Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK
| | - Lu-Yao Chen
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Nan Wu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Li Ma
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Mei Tang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Yang Yang
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Su An
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Xiao-Xi Guo
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Qian Hao
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
| | - Tian-Rui Xu
- Faculty of Life Science and Technology, Kunming University of Science and Technology, Kunming, China
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Nieto-Alamilla G, Márquez-Gómez R, García-Gálvez AM, Morales-Figueroa GE, Arias-Montaño JA. The Histamine H3 Receptor: Structure, Pharmacology, and Function. Mol Pharmacol 2016; 90:649-673. [PMID: 27563055 DOI: 10.1124/mol.116.104752] [Citation(s) in RCA: 109] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 08/24/2016] [Indexed: 01/06/2023] Open
Abstract
Among the four G protein-coupled receptors (H1-H4) identified as mediators of the biologic effects of histamine, the H3 receptor (H3R) is distinguished for its almost exclusive expression in the nervous system and the large variety of isoforms generated by alternative splicing of the corresponding mRNA. Additionally, it exhibits dual functionality as autoreceptor and heteroreceptor, and this enables H3Rs to modulate the histaminergic and other neurotransmitter systems. The cloning of the H3R cDNA in 1999 by Lovenberg et al. allowed for detailed studies of its molecular aspects. In this work, we review the characteristics of the H3R, namely, its structure, constitutive activity, isoforms, signal transduction pathways, regional differences in expression and localization, selective agonists, antagonists and inverse agonists, dimerization with other neurotransmitter receptors, and the main presynaptic and postsynaptic effects resulting from its activation. The H3R has attracted interest as a potential drug target for the treatment of several important neurologic and psychiatric disorders, such as Alzheimer and Parkinson diseases, Gilles de la Tourette syndrome, and addiction.
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Affiliation(s)
- Gustavo Nieto-Alamilla
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados (Cinvestav-IPN), Zacatenco, Ciudad de México, México
| | - Ricardo Márquez-Gómez
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados (Cinvestav-IPN), Zacatenco, Ciudad de México, México
| | - Ana-Maricela García-Gálvez
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados (Cinvestav-IPN), Zacatenco, Ciudad de México, México
| | - Guadalupe-Elide Morales-Figueroa
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados (Cinvestav-IPN), Zacatenco, Ciudad de México, México
| | - José-Antonio Arias-Montaño
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados (Cinvestav-IPN), Zacatenco, Ciudad de México, México
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Benarroch EE, Schmeichel AM, Parisi JE, Low PA. Histaminergic tuberomammillary neuron loss in multiple system atrophy and dementia with Lewy bodies. Mov Disord 2015; 30:1133-9. [DOI: 10.1002/mds.26287] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Revised: 05/06/2015] [Accepted: 05/11/2015] [Indexed: 12/11/2022] Open
Affiliation(s)
| | | | - Joseph E. Parisi
- Department of Neurology; Mayo Clinic; Rochester Minnesota USA
- Division of Anatomical Pathology; Mayo Clinic; Rochester Minnesota USA
| | - Phillip A. Low
- Department of Neurology; Mayo Clinic; Rochester Minnesota USA
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10
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Flores-Clemente C, Osorio-Espinoza A, Escamilla-Sánchez J, Leurs R, Arias JM, Arias-Montaño JA. A single-point mutation (Ala280Val) in the third intracellular loop alters the signalling properties of the human histamine H₃ receptor stably expressed in CHO-K1 cells. Br J Pharmacol 2014; 170:127-35. [PMID: 23713487 DOI: 10.1111/bph.12257] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 04/02/2013] [Accepted: 05/10/2013] [Indexed: 11/27/2022] Open
Abstract
BACKGROUND AND PURPOSE An alanine to valine exchange at amino acid position 280 (A280V) in the third intracellular loop of the human histamine H₃ receptor was first identified in a patient suffering from Shy-Drager syndrome and later reported as a risk factor for migraine. Here, we have compared the pharmacological and signalling properties of wild-type (hH₃ R(WT)) and A280V mutant (hH₃ R(A280V)) receptors stably expressed in CHO-K1 cells. EXPERIMENTAL APPROACH The hH₃ R(A280V) cDNA was created by overlapping extension PCR amplification. Receptor expression and affinity were assessed by radioligand (N-α-[methyl-³H]-histamine) binding to cell membranes, and receptor function by the inhibition of forskolin-induced cAMP accumulation and stimulation of ERK1/2 phosphorylation in intact cells, as well as stimulation of [³⁵S]-GTPγS binding to cell membranes. KEY RESULTS Both receptors were expressed at similar levels with no significant differences in their affinities for H₃ receptor ligands. Upon activation the hH₃ RWT was significantly more efficacious to inhibit forskolin-induced cAMP accumulation and to stimulate [³⁵S]-GTPγS binding, with no difference in pEC50 estimates. The hH₃ RWT was also more efficacious to stimulate ERK1/2 phosphorylation, but this difference was not significant. The inverse agonist ciproxifan was more efficacious at hH3 RWT to reduce [³⁵S]-GTPγS binding but, for both receptors, failed to enhance forskolin-induced cAMP accumulation. CONCLUSIONS AND IMPLICATIONS The A280V mutation reduces the signalling efficacy of the human H₃ receptor. This effect may be relevant to the pathophysiology of disorders associated with the mutation.
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Affiliation(s)
- Cecilia Flores-Clemente
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados (Cinvestav) del IPN, México
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11
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Morales-Figueroa GE, Márquez-Gómez R, González-Pantoja R, Escamilla-Sánchez J, Arias-Montaño JA. Histamine H3 receptor activation counteracts adenosine A2A receptor-mediated enhancement of depolarization-evoked [3H]-GABA release from rat globus pallidus synaptosomes. ACS Chem Neurosci 2014; 5:637-45. [PMID: 24884070 DOI: 10.1021/cn500001m] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
High levels of histamine H3 receptors (H3Rs) are found in the globus pallidus (GP), a neuronal nucleus in the basal ganglia involved in the control of motor behavior. By using rat GP isolated nerve terminals (synaptosomes), we studied whether H3R activation modified the previously reported enhancing action of adenosine A2A receptor (A2AR) stimulation on depolarization-evoked [(3)H]-GABA release. At 3 and 10 nM, the A2AR agonist CGS-21680 enhanced [(3)H]-GABA release induced by high K(+) (20 mM) and the effect of 3 nM CGS-21680 was prevented by the A2AR antagonist ZM-241385 (100 nM). The presence of presynaptic H3Rs was confirmed by the specific binding of N-α-[methyl-(3)H]-histamine to membranes from GP synaptosomes (maximum binding, Bmax, 1327 ± 79 fmol/mg protein; dissociation constant, Kd, 0.74 nM), which was inhibited by the H3R ligands immepip, clobenpropit, and A-331440 (inhibition constants, Ki, 0.28, 8.53, and 316 nM, respectively). Perfusion of synaptosomes with the H3R agonist immepip (100 nM) had no effect on K(+)-evoked [(3)H]-GABA release, but inhibited the stimulatory action of A2AR activation. In turn, the effect of immepip was blocked by the H3R antagonist clobenpropit, which had no significant effect of its own on K(+)-induced [(3)H]-GABA release. These data indicate that H3R activation selectively counteracts the facilitatory action of A2AR stimulation on GABA release from striato-pallidal projections.
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Affiliation(s)
- Guadalupe-Elide Morales-Figueroa
- Departamento de Fisiología,
Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, Av. Instituto Politécnico
Nacional 2508, Zacatenco, 07360 México, D.F., México
| | - Ricardo Márquez-Gómez
- Departamento de Fisiología,
Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, Av. Instituto Politécnico
Nacional 2508, Zacatenco, 07360 México, D.F., México
| | - Raúl González-Pantoja
- Departamento de Fisiología,
Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, Av. Instituto Politécnico
Nacional 2508, Zacatenco, 07360 México, D.F., México
| | - Juan Escamilla-Sánchez
- Departamento de Fisiología,
Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, Av. Instituto Politécnico
Nacional 2508, Zacatenco, 07360 México, D.F., México
| | - José-Antonio Arias-Montaño
- Departamento de Fisiología,
Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN, Av. Instituto Politécnico
Nacional 2508, Zacatenco, 07360 México, D.F., México
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Levetiracetam results in increased and decreased alcohol drinking with different access procedures in C57BL/6J mice. Behav Pharmacol 2014; 25:61-70. [PMID: 24322822 DOI: 10.1097/fbp.0000000000000019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The antiepileptic levetiracetam (LEV) has been investigated for the treatment of alcohol abuse. However, little is known about how LEV alters the behavioral effects of alcohol in laboratory animals. The acute effects of LEV on alcohol drinking by male C57BL/6J mice were investigated using two different drinking procedures, limited access [drinking-in-the-dark (DID)] and intermittent access (IA) drinking. In the first experiment (DID), mice had access to a single bottle containing alcohol or sucrose for 4 h every other day. In the second experiment (IA), mice had IA to two bottles, one containing alcohol or sucrose and one containing water, for 24 h on Monday, Wednesday, and Friday. In both experiments, mice were administered LEV (0.3-100 mg/kg intraperitoneally) or vehicle 30 min before access to the drinking solutions. In the DID mice, LEV increased alcohol intake from 4.3 to 5.4 g/kg, whereas in the IA mice LEV decreased alcohol intake from 4.8 to 3.0 g/kg in the first 4 h of access and decreased 24 h alcohol intake from 20 to ∼15 g/kg. These effects appear specific to alcohol, as LEV did not affect sucrose intake in either experiment. LEV appears to differentially affect drinking in animal models of moderate and heavier alcohol consumption.
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Varaschin RK, Rosenberg MJ, Hamilton DA, Savage DD. Differential effects of the histamine H(3) receptor agonist methimepip on dentate granule cell excitability, paired-pulse plasticity and long-term potentiation in prenatal alcohol-exposed rats. Alcohol Clin Exp Res 2014; 38:1902-11. [PMID: 24818819 PMCID: PMC5094461 DOI: 10.1111/acer.12430] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 03/21/2014] [Indexed: 11/29/2022]
Abstract
BACKGROUND We previously reported that prenatal alcohol-induced deficits in dentate gyrus (DG) long-term potentiation (LTP) are ameliorated by the histamine H3 receptor inverse agonist ABT-239. ABT-239 did not enhance LTP in control rats, suggesting that the possibility of a heightened H3 receptor-mediated inhibition of LTP in prenatal alcohol-exposed (PAE) offspring. METHODS To further investigate this mechanism, we examined the effect of methimepip, a selective histamine H3 receptor agonist, on DG granule cell responses and LTP in saccharin control and PAE rats. Long-Evans rat dams voluntarily consumed either a 0 or 5% ethanol solution 4 hours each day throughout gestation. Adult male offspring from these dams were anesthetized with urethane and electrodes implanted into the entorhinal cortical perforant path and the DG. RESULTS In control offspring, methimepip reduced the coupling of fast excitatory postsynaptic field potentials to population spikes (E-S coupling), the probability of glutamate release, as measured by paired-pulse ratio (PPR) and diminished DG LTP. Similar reductions in E-S coupling and LTP were observed in saline-treated PAE offspring. In contrast to the control group, methimepip did not exacerbate PAE-induced reductions in E-S coupling or LTP. CONCLUSIONS While the effects of methimepip in control offspring were consistent with speculation of a PAE-induced enhancement of H3 receptor-mediated inhibition of E-S coupling and LTP, the absence of an added effect of methimepip in PAE offspring could indicate either an inability to further inhibit these responses with methimepip in PAE rats or the presence of more complex regulatory neural interactions with in vivo recordings in PAE rats. Follow-up studies of H3 receptor-mediated responses in DG slice preparations are under way to provide clearer insights into the role of the H3 receptor regulation of excitatory transmission in PAE rats.
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Affiliation(s)
- Rafael K. Varaschin
- Department of Neurosciences, University of New Mexico, Albuquerque, New Mexico, 87131, USA
| | - Martina J. Rosenberg
- Department of Neurosciences, University of New Mexico, Albuquerque, New Mexico, 87131, USA
| | - Derek A. Hamilton
- Department of Neurosciences, University of New Mexico, Albuquerque, New Mexico, 87131, USA
- Department of Psychology, University of New Mexico, Albuquerque, New Mexico, 87131, USA
| | - Daniel D. Savage
- Department of Neurosciences, University of New Mexico, Albuquerque, New Mexico, 87131, USA
- Department of Psychology, University of New Mexico, Albuquerque, New Mexico, 87131, USA
- Department of Pediatrics, University of New Mexico, Albuquerque, New Mexico, 87131, USA
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Querejeta E, Alatorre A, Ríos A, Barrientos R, Oviedo-Chávez A, Bobadilla-Lugo RA, Delgado A. Striatal input- and rate-dependent effects of muscarinic receptors on pallidal firing. ScientificWorldJournal 2012; 2012:547638. [PMID: 22654627 PMCID: PMC3361291 DOI: 10.1100/2012/547638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 11/24/2011] [Indexed: 11/30/2022] Open
Abstract
The globus pallidus (GP) plays a key role in the overall basal ganglia (BG) activity. Despite evidence of cholinergic inputs to GP, their role in the spiking activity of GP neurons has not received attention. We examine the effect of local activation and blockade of muscarinic receptors (MRs) in the spontaneous firing of GP neurons both in normal and ipsilateral striatum-lesioned rats. We found that activation of MRs produces heterogeneous responses in both normal and ipsilateral striatum-lesioned rats: in normal rats the response evoked by MRs depends on the predrug basal firing rate; the inhibition evoked by MRs is higher in normal rats than in striatum-lesioned rats; the number of neurons that undergo inhibition is lower in striatum-lesioned rats than in normal rats. Our data suggest that modulation of MRs in the GP depends on the firing rate before their activation and on the integrity of the striato-pallidal pathway.
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Affiliation(s)
- Enrique Querejeta
- Sección de Estudios de Posgrado e Investigación, Escuela Superior de Medicina, Instituto Politécnico Nacional, Plan de San Luis y Díaz Mirón, 11340 México, DF, Mexico.
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15
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Aquino-Miranda G, Osorio-Espinoza A, Escamilla-Sánchez J, González-Pantoja R, Ortiz J, Arias-Montaño JA. Histamine H₃ receptors modulate depolarization-evoked [³H]-noradrenaline release from rat olfactory bulb slices. Neuropharmacology 2011; 62:1127-33. [PMID: 22115898 DOI: 10.1016/j.neuropharm.2011.11.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2011] [Revised: 11/04/2011] [Accepted: 11/08/2011] [Indexed: 11/26/2022]
Abstract
We have studied the effect of histamine H(3) receptor (H(3)R) activation on the depolarization-evoked release of labeled neurotransmitters from slices of the rat olfactory bulb (rOB). The presence of pre-synaptic H(3)Rs was evidenced by the specific binding of the H(3)R ligand N-α-[methyl-(3)H]histamine to membranes from rOB synaptosomes (maximum binding, B(max), 106 ± 19 fmol/mg protein; dissociation constant, K(d), 0.68 ± 0.11 nM) which was inhibited by selective H(3)R ligands (immepip, (R)(-)-α-methylhistamine (RAMH) and clobenpropit) with affinities similar to those previously reported for H(3)Rs expressed in other rat brain areas. Perfusion of rOB slices with the selective H(3)R agonist RAMH (0.1 and 1 μM) had no effect on the release of [(3)H]-γ-aminobutyric acid ([(3)H]-GABA), [(3)H]-d-aspartate, [(3)H]-dopamine or [(3)H]-5-hydroxytryptamine ([(3)H]-5-HT) evoked by depolarization with high K(+) (20 or 40 mM). [(3)H]-Noradrenaline release induced by 20 mM K(+) was reduced in a modest but significant manner by RAMH (94.9 ± 1.7% and 83.1 ± 2.1% of control release at 0.1 and 1 μM, respectively). The effect of 1 μM RAMH was blocked by the selective H(3)R antagonist/inverse agonist clobenpropit (5 μM). When tested alone clobenpropit and a second H(3)R antagonist/inverse agonist, ciproxifan (both at 1 μM) significantly increased K(+)-evoked [(3)H]-noradrenaline release to 119.4 ± 4.2% and 120.0 ± 3.7% of K(+) alone, respectively. Ciproxifan (1 μM) had no effect on the depolarization-evoked release of the other labeled neurotransmitters. These data indicate that H(3)Rs with constitutive activity modulate noradrenaline release in rOB, presumably through a pre-synaptic action. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.
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Affiliation(s)
- Guillermo Aquino-Miranda
- Departamento de Fisiología, Biofísica y Neurociencias, Centro de Investigación y de Estudios Avanzados del IPN (Cinvestav), Apdo. postal 14-740, 07000 México, D.F., Mexico
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