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Grychowska K, López-Sánchez U, Vitalis M, Canet G, Satała G, Olejarz-Maciej A, Gołębiowska J, Kurczab R, Pietruś W, Kubacka M, Moreau C, Walczak M, Blicharz-Futera K, Bento O, Bantreil X, Subra G, Bojarski AJ, Lamaty F, Becamel C, Zussy C, Chaumont-Dubel S, Popik P, Nury H, Marin P, Givalois L, Zajdel P. Superiority of the Triple-Acting 5-HT 6R/5-HT 3R Antagonist and MAO-B Reversible Inhibitor PZ-1922 over 5-HT 6R Antagonist Intepirdine in Alleviation of Cognitive Deficits in Rats. J Med Chem 2023; 66:14928-14947. [PMID: 37797083 PMCID: PMC10641814 DOI: 10.1021/acs.jmedchem.3c01482] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Indexed: 10/07/2023]
Abstract
The multifactorial origin and neurochemistry of Alzheimer's disease (AD) call for the development of multitarget treatment strategies. We report a first-in-class triple acting compound that targets serotonin type 6 and 3 receptors (5-HT-Rs) and monoamine oxidase type B (MAO-B) as an approach for treating AD. The key structural features required for MAO-B inhibition and 5-HT6R antagonism and interaction with 5-HT3R were determined using molecular dynamic simulations and cryo-electron microscopy, respectively. Bioavailable PZ-1922 reversed scopolamine-induced cognitive deficits in the novel object recognition test. Furthermore, it displayed superior pro-cognitive properties compared to intepirdine (a 5-HT6R antagonist) in the AD model, which involved intracerebroventricular injection of an oligomeric solution of amyloid-β peptide (oAβ) in the T-maze test in rats. PZ-1922, but not intepirdine, restored levels of biomarkers characteristic of the debilitating effects of oAβ. These data support the potential of a multitarget approach involving the joint modulation of 5-HT6R/5-HT3R/MAO-B in AD.
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Affiliation(s)
- Katarzyna Grychowska
- Faculty
of Pharmacy, Jagiellonian University Medical
College, 9 Medyczna Str., 30-688 Kraków, Poland
| | | | - Mathieu Vitalis
- Molecular
Mechanisms in Neurodegenerative Dementia (MMDN) Laboratory, University of Montpellier, EPHE-PSL, INSERM U1198, 34-095 Montpellier, France
| | - Geoffrey Canet
- Faculty
of Medicine, Laval University, CR-CHUQ, G1 V 4G2 Québec
City (QC), Canada
| | - Grzegorz Satała
- Maj
Institute of Pharmacology, Polish Academy
of Sciences, 12 Smętna Str., 31-324 Kraków, Poland
| | - Agnieszka Olejarz-Maciej
- Faculty
of Pharmacy, Jagiellonian University Medical
College, 9 Medyczna Str., 30-688 Kraków, Poland
| | - Joanna Gołębiowska
- Maj
Institute of Pharmacology, Polish Academy
of Sciences, 12 Smętna Str., 31-324 Kraków, Poland
| | - Rafał Kurczab
- Maj
Institute of Pharmacology, Polish Academy
of Sciences, 12 Smętna Str., 31-324 Kraków, Poland
| | - Wojciech Pietruś
- Maj
Institute of Pharmacology, Polish Academy
of Sciences, 12 Smętna Str., 31-324 Kraków, Poland
| | - Monika Kubacka
- Faculty
of Pharmacy, Jagiellonian University Medical
College, 9 Medyczna Str., 30-688 Kraków, Poland
| | | | - Maria Walczak
- Faculty
of Pharmacy, Jagiellonian University Medical
College, 9 Medyczna Str., 30-688 Kraków, Poland
| | - Klaudia Blicharz-Futera
- Faculty
of Pharmacy, Jagiellonian University Medical
College, 9 Medyczna Str., 30-688 Kraków, Poland
| | - Ophélie Bento
- IBMM,
Université
de Montpellier, CNRS, ENSCM, 34-293 Montpellier, France
- Institut
de Génomique Fonctionnelle, Université
de Montpellier, CNRS, INSERM, 34-094 Montpellier, France
| | - Xavier Bantreil
- IBMM,
Université
de Montpellier, CNRS, ENSCM, 34-293 Montpellier, France
| | - Gilles Subra
- IBMM,
Université
de Montpellier, CNRS, ENSCM, 34-293 Montpellier, France
| | - Andrzej J. Bojarski
- Maj
Institute of Pharmacology, Polish Academy
of Sciences, 12 Smętna Str., 31-324 Kraków, Poland
| | - Frédéric Lamaty
- IBMM,
Université
de Montpellier, CNRS, ENSCM, 34-293 Montpellier, France
| | - Carine Becamel
- Institut
de Génomique Fonctionnelle, Université
de Montpellier, CNRS, INSERM, 34-094 Montpellier, France
| | - Charleine Zussy
- Molecular
Mechanisms in Neurodegenerative Dementia (MMDN) Laboratory, University of Montpellier, EPHE-PSL, INSERM U1198, 34-095 Montpellier, France
| | - Séverine Chaumont-Dubel
- Institut
de Génomique Fonctionnelle, Université
de Montpellier, CNRS, INSERM, 34-094 Montpellier, France
| | - Piotr Popik
- Maj
Institute of Pharmacology, Polish Academy
of Sciences, 12 Smętna Str., 31-324 Kraków, Poland
| | - Hugues Nury
- Univ.
Grenoble Alpes, CNRS, CEA, IBS, F-38000 Grenoble, France
| | - Philippe Marin
- Institut
de Génomique Fonctionnelle, Université
de Montpellier, CNRS, INSERM, 34-094 Montpellier, France
| | - Laurent Givalois
- Molecular
Mechanisms in Neurodegenerative Dementia (MMDN) Laboratory, University of Montpellier, EPHE-PSL, INSERM U1198, 34-095 Montpellier, France
- Faculty
of Medicine, Laval University, CR-CHUQ, G1 V 4G2 Québec
City (QC), Canada
- CNRS, 75-016 Paris, France
| | - Paweł Zajdel
- Faculty
of Pharmacy, Jagiellonian University Medical
College, 9 Medyczna Str., 30-688 Kraków, Poland
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Zajdel P, Grychowska K, Mogilski S, Kurczab R, Satała G, Bugno R, Kos T, Gołębiowska J, Malikowska-Racia N, Nikiforuk A, Chaumont-Dubel S, Bantreil X, Pawłowski M, Martinez J, Subra G, Lamaty F, Marin P, Bojarski AJ, Popik P. Structure-Based Design and Optimization of FPPQ, a Dual-Acting 5-HT 3 and 5-HT 6 Receptor Antagonist with Antipsychotic and Procognitive Properties. J Med Chem 2021; 64:13279-13298. [PMID: 34467765 PMCID: PMC8474115 DOI: 10.1021/acs.jmedchem.1c00224] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
In line with recent clinical trials demonstrating that ondansetron, a 5-HT3 receptor (5-HT3R) antagonist, ameliorates cognitive deficits of schizophrenia and the known procognitive effects of 5-HT6 receptor (5-HT6R) antagonists, we applied the hybridization strategy to design dual-acting 5-HT3/5-HT6R antagonists. We identified the first-in-class compound FPPQ, which behaves as a 5-HT3R antagonist and a neutral antagonist 5-HT6R of the Gs pathway. FPPQ shows selectivity over 87 targets and decent brain penetration. Likewise, FPPQ inhibits phencyclidine (PCP)-induced hyperactivity and displays procognitive properties in the novel object recognition task. In contrast to FPPQ, neither 5-HT6R inverse agonist SB399885 nor neutral 5-HT6R antagonist CPPQ reversed (PCP)-induced hyperactivity. Thus, combination of 5-HT3R antagonism and 5-HT6R antagonism, exemplified by FPPQ, contributes to alleviating the positive-like symptoms. Present findings reveal critical structural features useful in a rational polypharmacological approach to target 5-HT3/5-HT6 receptors and encourage further studies on dual-acting 5-HT3/5-HT6R antagonists for the treatment of psychiatric disorders.
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Affiliation(s)
- Paweł Zajdel
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Str., 30-688 Kraków, Poland
| | - Katarzyna Grychowska
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Str., 30-688 Kraków, Poland
| | - Szczepan Mogilski
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Str., 30-688 Kraków, Poland
| | - Rafał Kurczab
- Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Str., 31-343 Kraków, Poland
| | - Grzegorz Satała
- Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Str., 31-343 Kraków, Poland
| | - Ryszard Bugno
- Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Str., 31-343 Kraków, Poland
| | - Tomasz Kos
- Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Str., 31-343 Kraków, Poland
| | - Joanna Gołębiowska
- Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Str., 31-343 Kraków, Poland
| | - Natalia Malikowska-Racia
- Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Str., 31-343 Kraków, Poland
| | - Agnieszka Nikiforuk
- Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Str., 31-343 Kraków, Poland
| | - Séverine Chaumont-Dubel
- Institut de Génomique Fonctionelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier, France
| | - Xavier Bantreil
- IBMM, Université de Montpellier, CNRS, ENSCM, 34095 Montpellier, France
| | - Maciej Pawłowski
- Faculty of Pharmacy, Jagiellonian University Medical College, 9 Medyczna Str., 30-688 Kraków, Poland
| | - Jean Martinez
- IBMM, Université de Montpellier, CNRS, ENSCM, 34095 Montpellier, France
| | - Gilles Subra
- IBMM, Université de Montpellier, CNRS, ENSCM, 34095 Montpellier, France
| | - Frédéric Lamaty
- IBMM, Université de Montpellier, CNRS, ENSCM, 34095 Montpellier, France
| | - Philippe Marin
- Institut de Génomique Fonctionelle, Université de Montpellier, CNRS, INSERM, 34094 Montpellier, France
| | - Andrzej J Bojarski
- Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Str., 31-343 Kraków, Poland
| | - Piotr Popik
- Maj Institute of Pharmacology, Polish Academy of Sciences, 12 Smętna Str., 31-343 Kraków, Poland
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3
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Granisetron, a selective 5-HT3 antagonist, reduces L-3,4-dihydroxyphenylalanine-induced abnormal involuntary movements in the 6-hydroxydopamine-lesioned rat. Behav Pharmacol 2020; 32:43-53. [PMID: 33399295 DOI: 10.1097/fbp.0000000000000601] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Administration of L-3,4-dihydroxyphenylalanine (L-DOPA) provides Parkinson's disease patients with effective symptomatic relief. However, long-term L-DOPA therapy is often marred by complications such as dyskinesia. We have previously demonstrated that serotonin type 3 (5-HT3) receptor blockade with the clinically available and highly selective antagonist ondansetron alleviates dyskinesia in the 6-hydroxydopamine (6-OHDA)-lesioned rat. Here, we sought to explore the antidyskinetic efficacy of granisetron, another clinically available 5-HT3 receptor antagonist. Rats were rendered hemi-parkinsonian by 6-OHDA injection in the medial forebrain bundle. Following induction of stable abnormal involuntary movements (AIMs), granisetron (0.0001, 0.001, 0.01, 0.1 and 1 mg/kg) or vehicle was acutely administered in combination with L-DOPA and the severity of AIMs, both duration and amplitude, was determined. We also assessed the effect of granisetron on L-DOPA antiparkinsonian action by performing the cylinder test. Adding granisetron (0.0001, 0.001, 0.01, 0.1 and 1 mg/kg) to L-DOPA resulted in a significant reduction of AIMs duration and amplitude, with certain parameters being reduced by as much as 38 and 45% (P < 0.05 and P < 0.001, respectively). The antidyskinetic effect of granisetron was not accompanied by a reduction of L-DOPA antiparkinsonian action. These results suggest that 5-HT3 blockade may reduce L-DOPA-induced dyskinesia without impairing the therapeutic efficacy of L-DOPA. However, a U-shaped dose-response curve obtained with certain parameters may limit the therapeutic potential of this strategy and require further investigation.
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Sato T, Hirai Y, Su S, Zimo W, Yasuura N, Inui T, Funahashi M. Involvement of the area postrema and the nucleus tractus solitarius in the emetogenic action of emetine in rats. J Oral Biosci 2020; 62:310-314. [PMID: 33065316 DOI: 10.1016/j.job.2020.10.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2020] [Revised: 10/06/2020] [Accepted: 10/07/2020] [Indexed: 12/16/2022]
Abstract
OBJECTIVES The aim of the present study was to demonstrate the effective dose of emetine for inducing nausea and/or emesis, and the effects of emetine on the excitability of central neurons in the area postrema (AP) and the nucleus tractus solitarius (NTS). METHODS Rats were used as experimental animals. We measured the conditioned taste aversion (CTA) induced by the intraperitoneal administration of emetine solution (0.03, 0.1, 0.3, 0.5, and 1.0 mM in saline) and that of only saline. We also performed immunohistochemical analyses of c-Fos expression in the area postrema and the NTS, to examine changes in the excitability of brainstem neurons that may be responsible for emetine-induced nausea and/or emesis. RESULTS The emetine-induced CTA occurred in a dose-dependent manner. The half maximal inhibitory concentration (IC50) of emetine on the saccharin preference was calculated to be 0.348 mM using the Hill equation. In the animals injected with emetine (0.5 and 1.0 mM), many c-Fos-like immunoreactive (Fos-ir) cells were observed in the area postrema and the NTS, while few Fos-ir cells were identified in the animals injected with saline. The average number of Fos-ir cells in the area postrema and the NTS was significantly larger in animals injected with emetine than in animals injected with saline. CONCLUSIONS The present study demonstrated a dose-responsive manner of emetine effects and emetine-induced upregulation of neuronal excitability in the area postrema and the NTS that form a part of the induction mechanisms of emetine-induced nausea and/or emesis.
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Affiliation(s)
- Takanori Sato
- Oral Physiology, Department of Oral Functional Science, Faculty of Dental Medicine and Graduate School of Dental Medicine, Hokkaido University. Kita 13, Nishi 7, Kita-ku, Sapporo, 060-8586, Japan.
| | - Yoshiyuki Hirai
- Oral Physiology, Department of Oral Functional Science, Faculty of Dental Medicine and Graduate School of Dental Medicine, Hokkaido University. Kita 13, Nishi 7, Kita-ku, Sapporo, 060-8586, Japan.
| | - Shaoyi Su
- Oral Physiology, Department of Oral Functional Science, Faculty of Dental Medicine and Graduate School of Dental Medicine, Hokkaido University. Kita 13, Nishi 7, Kita-ku, Sapporo, 060-8586, Japan.
| | - Wei Zimo
- Oral Physiology, Department of Oral Functional Science, Faculty of Dental Medicine and Graduate School of Dental Medicine, Hokkaido University. Kita 13, Nishi 7, Kita-ku, Sapporo, 060-8586, Japan.
| | - Nanae Yasuura
- Oral Physiology, Department of Oral Functional Science, Faculty of Dental Medicine and Graduate School of Dental Medicine, Hokkaido University. Kita 13, Nishi 7, Kita-ku, Sapporo, 060-8586, Japan.
| | - Tadashi Inui
- Oral Physiology, Department of Oral Functional Science, Faculty of Dental Medicine and Graduate School of Dental Medicine, Hokkaido University. Kita 13, Nishi 7, Kita-ku, Sapporo, 060-8586, Japan.
| | - Makoto Funahashi
- Oral Physiology, Department of Oral Functional Science, Faculty of Dental Medicine and Graduate School of Dental Medicine, Hokkaido University. Kita 13, Nishi 7, Kita-ku, Sapporo, 060-8586, Japan.
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Fakhfouri G, Rahimian R, Dyhrfjeld-Johnsen J, Zirak MR, Beaulieu JM. 5-HT 3 Receptor Antagonists in Neurologic and Neuropsychiatric Disorders: The Iceberg Still Lies beneath the Surface. Pharmacol Rev 2019; 71:383-412. [PMID: 31243157 DOI: 10.1124/pr.118.015487] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
5-HT3 receptor antagonists, first introduced to the market in the mid-1980s, are proven efficient agents to counteract chemotherapy-induced emesis. Nonetheless, recent investigations have shed light on unappreciated dimensions of this class of compounds in conditions with an immunoinflammatory component as well as in neurologic and psychiatric disorders. The promising findings from multiple studies have unveiled several beneficial effects of these compounds in multiple sclerosis, stroke, Alzheimer disease, and Parkinson disease. Reports continue to uncover important roles for 5-HT3 receptors in the physiopathology of neuropsychiatric disorders, including depression, anxiety, drug abuse, and schizophrenia. This review addresses the potential of 5-HT3 receptor antagonists in neurology- and neuropsychiatry-related disorders. The broad therapeutic window and high compliance observed with these agents position them as suitable prototypes for the development of novel pharmacotherapeutics with higher efficacy and fewer adverse effects.
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Affiliation(s)
- Gohar Fakhfouri
- Department of Psychiatry and Neuroscience, Faculty of Medicine, CERVO Brain Research Centre, Laval University, Quebec, Quebec, Canada (G.F., R.R.); Sensorion SA, Montpellier, France (J.D.-J.); Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran (M.R.Z.); and Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada (J.-M.B.)
| | - Reza Rahimian
- Department of Psychiatry and Neuroscience, Faculty of Medicine, CERVO Brain Research Centre, Laval University, Quebec, Quebec, Canada (G.F., R.R.); Sensorion SA, Montpellier, France (J.D.-J.); Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran (M.R.Z.); and Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada (J.-M.B.)
| | - Jonas Dyhrfjeld-Johnsen
- Department of Psychiatry and Neuroscience, Faculty of Medicine, CERVO Brain Research Centre, Laval University, Quebec, Quebec, Canada (G.F., R.R.); Sensorion SA, Montpellier, France (J.D.-J.); Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran (M.R.Z.); and Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada (J.-M.B.)
| | - Mohammad Reza Zirak
- Department of Psychiatry and Neuroscience, Faculty of Medicine, CERVO Brain Research Centre, Laval University, Quebec, Quebec, Canada (G.F., R.R.); Sensorion SA, Montpellier, France (J.D.-J.); Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran (M.R.Z.); and Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada (J.-M.B.)
| | - Jean-Martin Beaulieu
- Department of Psychiatry and Neuroscience, Faculty of Medicine, CERVO Brain Research Centre, Laval University, Quebec, Quebec, Canada (G.F., R.R.); Sensorion SA, Montpellier, France (J.D.-J.); Department of Pharmacodynamics and Toxicology, School of Pharmacy, Mashhad University of Medical Sciences, Mashhad, Iran (M.R.Z.); and Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada (J.-M.B.)
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Wilhelm EA, Soares PS, Reis AS, Barth A, Freitas BG, Motta KP, Lemos BB, Vogt AG, da Fonseca CAR, Araujo DR, Barcellos AM, Perin G, Luchese C. Se - [(2,2-Dimethyl-1,3-dioxolan-4-yl) methyl] 4-chlorobenzoselenolate reduces the nociceptive and edematogenic response by chemical noxious stimuli in mice: Implications of multi-target actions. Pharmacol Rep 2019; 71:1201-1209. [PMID: 31669884 DOI: 10.1016/j.pharep.2019.07.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2019] [Revised: 07/03/2019] [Accepted: 07/18/2019] [Indexed: 12/28/2022]
Abstract
BACKGROUND The present study evaluated the antioxidant, antinociceptive and anti-edematogenic effects of Se-[(2,2-dimethyl-1,3-dioxolan-4-yl) methyl] 4-chlorobenzoselenolate (Se-DMC). METHODS In vitro experiments were carried out to evaluate Se-DMC antioxidant action. Thiobarbituric acid reactive species levels, 2,2'-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-thylbenzthiazoline-6-sulfonic acid) radicals scavenging and glutathione S-transferase-like activity were determined. Male Swiss mice were orally pretreated with Se-DMC (1, 10 and 50 mg/kg), meloxicam (50 mg/kg) or vehicle 30 min prior to acetic acid or glutamate test. To extend our knowledge of the pharmacological properties of this compound, it was tested in an inflammatory model through ear edema induced by croton oil. The contribution of glutamatergic and serotonergic systems was also investigated. RESULTS In vitro experiments revealed that Se-DMC exerts antioxidant activity. Nociception induced by glutamate or acetic acid was reduced by Se-DMC or meloxicam. Se-DMC diminished the paw edema formation induced by glutamate, while meloxicam did not show any effect. Se-DMC and meloxicam decreased the ear edema formation and protected against the increase in myeloperoxidase activity in mice ear induced by croton oil. The pretreatment of animals with MK-801 did not alter antinociception caused by Se-DMC in the glutamate test. The antinociceptive effect exerted by Se-DMC in the acetic acid test was reverted by the pretreatment of mice with different serotonergic antagonists (WAY100635, ketanserin and pindolol). CONCLUSIONS Data presented here showed that the modulation of serotonergic and glutamatergic systems and the anti-inflammatory and antioxidant actions could contribute to the antinociceptive and anti-edematogenic effects of Se-DMC and it supported the therapeutic potential of this compound.
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Affiliation(s)
- Ethel A Wilhelm
- Laboratório de Pesquisa em Farmacologia Bioquímica, CCQFA - Universidade Federal de Pelotas, UFPel, Pelotas, RS, Brazil.
| | - Paola S Soares
- Laboratório de Pesquisa em Farmacologia Bioquímica, CCQFA - Universidade Federal de Pelotas, UFPel, Pelotas, RS, Brazil
| | - Angélica S Reis
- Laboratório de Pesquisa em Farmacologia Bioquímica, CCQFA - Universidade Federal de Pelotas, UFPel, Pelotas, RS, Brazil
| | - Anelise Barth
- Laboratório de Pesquisa em Farmacologia Bioquímica, CCQFA - Universidade Federal de Pelotas, UFPel, Pelotas, RS, Brazil
| | - Barbara G Freitas
- Laboratório de Pesquisa em Farmacologia Bioquímica, CCQFA - Universidade Federal de Pelotas, UFPel, Pelotas, RS, Brazil
| | - Ketlyn P Motta
- Laboratório de Pesquisa em Farmacologia Bioquímica, CCQFA - Universidade Federal de Pelotas, UFPel, Pelotas, RS, Brazil
| | - Briana B Lemos
- Laboratório de Pesquisa em Farmacologia Bioquímica, CCQFA - Universidade Federal de Pelotas, UFPel, Pelotas, RS, Brazil
| | - Ane G Vogt
- Laboratório de Pesquisa em Farmacologia Bioquímica, CCQFA - Universidade Federal de Pelotas, UFPel, Pelotas, RS, Brazil
| | - Caren A R da Fonseca
- Laboratório de Pesquisa em Farmacologia Bioquímica, CCQFA - Universidade Federal de Pelotas, UFPel, Pelotas, RS, Brazil
| | - Daniela R Araujo
- Laboratório de Síntese Orgânica Limpa, CCQFA - Universidade Federal de Pelotas - UFPel, Pelotas, RS, Brazil
| | - Angelita M Barcellos
- Laboratório de Síntese Orgânica Limpa, CCQFA - Universidade Federal de Pelotas - UFPel, Pelotas, RS, Brazil
| | - Gelson Perin
- Laboratório de Síntese Orgânica Limpa, CCQFA - Universidade Federal de Pelotas - UFPel, Pelotas, RS, Brazil
| | - Cristiane Luchese
- Laboratório de Pesquisa em Farmacologia Bioquímica, CCQFA - Universidade Federal de Pelotas, UFPel, Pelotas, RS, Brazil.
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7
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Gaudette F, Bédard D, Kwan C, Frouni I, Hamadjida A, Beaudry F, Huot P. Highly sensitive HPLC-MS/MS assay for the quantitation of ondansetron in rat plasma and rat brain tissue homogenate following administration of a very low subcutaneous dose. J Pharm Biomed Anal 2019; 175:112766. [DOI: 10.1016/j.jpba.2019.07.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Revised: 07/04/2019] [Accepted: 07/07/2019] [Indexed: 10/26/2022]
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8
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Yu Y, Zhu W, Liang Q, Liu J, Yang X, Sun G. Tropisetron attenuates lipopolysaccharide induced neuroinflammation by inhibiting NF-κB and SP/NK1R signaling pathway. J Neuroimmunol 2018; 320:80-86. [PMID: 29759144 DOI: 10.1016/j.jneuroim.2018.05.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Revised: 05/02/2018] [Accepted: 05/02/2018] [Indexed: 12/22/2022]
Abstract
Tropisetron, an antagonist of serotonin type 3 receptors (5-HT3Rs), has been investigated in colonic inflammatory process. Since substance P/neurokinin 1 receptor (SP/NK1R) signaling pathway plays a key role in several sensory neuronal inflammatory. We evaluated the anti-inflammatory activity of tropisetron in mice cerebral cortex, and discovered that it was a potential inhibitor in LPS-mediated neuron inflammation through SP/NK1R signaling pathway. We found that tropisetron significantly reduced the increased number of iba-1 positive microglia, down-regulated the gene transcription and protein expression of IL-1β,IL-6 and TNF-α in LPS stimulated cerebral cortex. To characterize the inhibitory mechanism of tropisetron at the SP response in inflammation, we further examined the effect of tropisetron on NF-κB and SP/NK1R signaling pathway in the process of mice cerebral cortex inflammation. We found that tropisetron inhibited the gene transcription and protein expression of NF-κB, SP, NK1R via inhibiting 5-HT3R activity. These findings might provide new insights into the anti-inflammatory activities of 5-HT3R inhibitor tropisetron, which would be the interaction of serotonin receptor signaling and SP/NK1R pathway. These might highlight their potential to design novel therapeutic strategies to manage inflammatory diseases.
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Affiliation(s)
- Yan Yu
- Department of pharmacy, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
| | - Wanhu Zhu
- Department of pharmacy, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
| | - Qing Liang
- Department of pharmacy, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
| | - Jing Liu
- Department of pharmacy, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
| | - Xu Yang
- Department of pharmacy, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China
| | - Guangchun Sun
- Department of pharmacy, The Fifth People's Hospital of Shanghai, Fudan University, Shanghai, China.
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Kim KJ, Jeun SH, Sung KW. Lamotrigine, an antiepileptic drug, inhibits 5-HT 3 receptor currents in NCB-20 neuroblastoma cells. THE KOREAN JOURNAL OF PHYSIOLOGY & PHARMACOLOGY : OFFICIAL JOURNAL OF THE KOREAN PHYSIOLOGICAL SOCIETY AND THE KOREAN SOCIETY OF PHARMACOLOGY 2017; 21:169-177. [PMID: 28280410 PMCID: PMC5343050 DOI: 10.4196/kjpp.2017.21.2.169] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 11/29/2016] [Accepted: 12/18/2016] [Indexed: 12/26/2022]
Abstract
Lamotrigine is an antiepileptic drug widely used to treat epileptic seizures. Using whole-cell voltage clamp recordings in combination with a fast drug application approach, we investigated the effects of lamotrigine on 5-hydroxytryptamine (5-HT)3 receptors in NCB-20 neuroblastoma cells. Co-application of lamotrigine (1~300 µM) resulted in a concentration-dependent reduction in peak amplitude of currents induced by 3 µM of 5-HT for an IC50 value of 28.2±3.6 µM with a Hill coefficient of 1.2±0.1. These peak amplitude decreases were accompanied by the rise slope reduction. In addition, 5-HT3-mediated currents evoked by 1 mM dopamine, a partial 5-HT3 receptor agonist, were inhibited by lamotrigine co-application. The EC50 of 5-HT for 5-HT3 receptor currents were shifted to the right by co-application of lamotrigine without a significant change of maximal effect. Currents activated by 5-HT and lamotrigine co-application in the presence of 1 min pretreatment of lamotrigine were similar to those activated by 5-HT and lamotrigine co-application alone. Moreover, subsequent application of lamotrigine in the presence of 5-HT and 5-hydroxyindole, known to attenuate 5-HT3 receptor desensitization, inhibited 5-HT3 receptor currents in a concentration-dependent manner. The deactivation of 5-HT3 receptor was delayed by washing with an external solution containing lamotrigine. Lamotrigine accelerated the desensitization process of 5-HT3 receptors. There was no voltage-dependency in the inhibitory effects of lamotrigine on the 5-HT3 receptor currents. These results indicate that lamotrigine inhibits 5-HT3-activated currents in a competitive manner by binding to the open state of the channels and blocking channel activation or accelerating receptor desensitization.
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Affiliation(s)
- Ki Jung Kim
- Department of Physiology, Augusta University, Augusta, GA 30912, USA
| | - Seung Hyun Jeun
- Department of Pharmacology, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
| | - Ki-Wug Sung
- Department of Pharmacology, College of Medicine, The Catholic University of Korea, Seoul 06591, Korea
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10
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Kim HW, Kang JI, Lee SH, An SK, Sohn SY, Hwang EH, Lee SY, Kim SJ. Common variants of HTR3 genes are associated with obsessive-compulsive disorder and its phenotypic expression. Sci Rep 2016; 6:32564. [PMID: 27616601 PMCID: PMC5018838 DOI: 10.1038/srep32564] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 08/09/2016] [Indexed: 12/24/2022] Open
Abstract
Evidence from literature supports the existence of associations between serotonin-related genetic variants and obsessive-compulsive disorder (OCD), but few studies have explored the involvement of serotonin receptor type 3 genes (HTR3) in OCD. To identify whether HTR3 variability affects an individual’s susceptibility to OCD, we examined 10 HTR3 variants in 596 individuals with OCD and 599 controls. A significant difference existed in the genotypic distribution of the HTR3B variant rs1176744 between individuals with OCD and controls (odds ratio [OR] = 0.74, 95% confidence interval [CI] = 0.60–0.91, P = 0.0043). A protective haplotype in HTR3B was also associated with OCD (OR = 0.77, CI = 0.63–0.95, permutated P = 0.0179). Analyses of OCD sub-phenotypes demonstrated significant associations between rs3758987 and early onset OCD in male subjects (OR = 0.49, CI = 0.31–0.79, P = 0.0031) and among rs6766410, rs6443930, and the cleaning dimension in female subjects (OR = 0.36, CI = 0.18–0.69, P = 0.0016 and OR = 0.47, CI = 0.29–0.79, P = 0.0030, respectively). Additionally, rs6766410 was related to contamination-based disgust in OCD (P = 0.0044). These results support that common HTR3 variants are involved in OCD and some of its clinical phenotypes.
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Affiliation(s)
- Hae Won Kim
- Department of Psychiatry, Yonsei University College of Medicine, Seoul, Republic of Korea.,Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Jee In Kang
- Department of Psychiatry, Yonsei University College of Medicine, Seoul, Republic of Korea.,Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Sang-Hyuk Lee
- Department of Psychiatry, CHA Bundang Medical Center, CHA University, Seongnam, Republic of Korea
| | - Suk Kyoon An
- Department of Psychiatry, Yonsei University College of Medicine, Seoul, Republic of Korea.,Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Sung Yun Sohn
- Department of Psychiatry, Yonsei University College of Medicine, Seoul, Republic of Korea.,Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Eun Hee Hwang
- Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
| | - Su Young Lee
- Department of Psychiatry, Cheil General Hospital &Women's Healthcare Center, Dankook University College of Medicine, Seoul, Republic of Korea
| | - Se Joo Kim
- Department of Psychiatry, Yonsei University College of Medicine, Seoul, Republic of Korea.,Institute of Behavioral Science in Medicine, Yonsei University College of Medicine, Seoul, Republic of Korea
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Gupta D, Prabhakar V, Radhakrishnan M. 5HT3 receptors: Target for new antidepressant drugs. Neurosci Biobehav Rev 2016; 64:311-25. [PMID: 26976353 DOI: 10.1016/j.neubiorev.2016.03.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2015] [Revised: 02/29/2016] [Accepted: 03/01/2016] [Indexed: 12/31/2022]
Abstract
5HT3 receptors (5HT3Rs) have long been identified as a potential target for antidepressants. Several studies have reported that antagonism of 5HT3Rs produces antidepressant-like effects. However, the exact role of 5HT3Rs and the mode of antidepressant action of 5HT3R antagonists still remain a mystery. Here, we provide a comprehensive overview of 5HT3Rs: (a) regional and subcellular distribution of 5HT3Rs in discrete brain regions, (b) preclinical and clinical evidence supporting the antidepressant effect of 5HT3R antagonists, and (c) neurochemical, biological and neurocellular signaling pathways associated with the antidepressant action of 5HT3R antagonists. 5HT3Rs located on the serotonergic and other neurotransmitter interneuronal projections control their release and affect mood and emotional behavior; however, new evidence suggests that apart from modulating the neurotransmitter functions, 5HT3R antagonists have protective effects in the pathogenic events including hypothalamic-pituitary-adrenal-axis hyperactivity, brain oxidative stress and impaired neuronal plasticity, pointing to hereby unknown and novel mechanisms of their antidepressant action. Nonetheless, further investigations are warranted to establish the exact role of 5HT3Rs in depression and antidepressant action of 5HT3R antagonists.
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Affiliation(s)
- Deepali Gupta
- Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan 333031, India.
| | - Visakh Prabhakar
- Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan 333031, India.
| | - Mahesh Radhakrishnan
- Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan 333031, India.
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12
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Garay RP, Bourin M, de Paillette E, Samalin L, Hameg A, Llorca PM. Potential serotonergic agents for the treatment of schizophrenia. Expert Opin Investig Drugs 2015; 25:159-70. [DOI: 10.1517/13543784.2016.1121995] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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13
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Ohno Y, Shimizu S, Tokudome K, Kunisawa N, Sasa M. New insight into the therapeutic role of the serotonergic system in Parkinson's disease. Prog Neurobiol 2015; 134:104-21. [DOI: 10.1016/j.pneurobio.2015.09.005] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 08/17/2015] [Accepted: 09/05/2015] [Indexed: 11/30/2022]
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Wu ZS, Cheng H, Jiang Y, Melcher K, Xu HE. Ion channels gated by acetylcholine and serotonin: structures, biology, and drug discovery. Acta Pharmacol Sin 2015; 36:895-907. [PMID: 26238288 PMCID: PMC4564887 DOI: 10.1038/aps.2015.66] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 06/24/2015] [Indexed: 12/17/2022] Open
Abstract
The nicotinic acetylcholine receptors (nAChRs) and the 5-HT3 receptors (5-HT3Rs) are cation-selective members of the pentameric ligand-gated ion channels (pLGICs), which are oligomeric protein assemblies that convert a chemical signal into an ion flux through postsynaptic membrane. They are critical components for synaptic transmission in the nervous system, and their dysfunction contributes to many neurological disorders. The diverse subunit compositions of pLGICs give rise to complex mechanisms of ligand recognition, channel gating, and ion-selective permeability, which have been demonstrated in numerous electrophysiological and molecular biological studies, and unraveled by progress in studying the structural biology of this protein family. In this review, we discuss recent insights into the structural and functional basis of two cation-selective pLGICs, the nAChR and the 5-HT3R, including their subunit compositions, ligand binding, and channel gating mechanisms. We also discuss their relevant pharmacology and drug discovery for treating various neurological disorders. Finally, we review a model of two alternative ion conducting pathways based on the latest 5-HT3A crystal structure.
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Gupta D, Radhakrishnan M, Kurhe Y. Effect of a novel 5-HT3 receptor antagonist 4i, in corticosterone-induced depression-like behavior and oxidative stress in mice. Steroids 2015; 96:95-102. [PMID: 25668613 DOI: 10.1016/j.steroids.2015.01.021] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2014] [Revised: 01/21/2015] [Accepted: 01/23/2015] [Indexed: 11/23/2022]
Abstract
Stress in our daily life severely affects the normal physiology of the biological system. Dysregulation of hypothalamic-pituitary-adrenal (HPA) axis has been implicated in the development of depression-like behavior, which remains under diagnosed and poorly treated. Exogenous corticosterone (CORT) administration has been demonstrated to develop a depression model, which has shown to mimic HPA-axis induced depression-like state in rodents. In the present study, the effect of a novel 5HT3 receptor, 4i was examined on CORT induced depression in mice. CORT (30mg/kg, subcutaneously) was given for 4-weeks to mice in control group, while mice in drug treated group were given 4i (0.5-1mg/kg, intraperitoneally)/fluoxetine (as a positive control, 10mg/kg), for the last 2-weeks of CORT dosing. Repeated CORT dosing caused depression-like behavior in mice as indicated by increased despair effects in forced swim test (FST) and anhedonia in sucrose preference test. In addition, CORT administration induced oxidative load in the brain with significant increase in pro-oxidant (lipid peroxidation and nitrite levels) markers and a substantial decline in anti-oxidant defense (catalase and reduced glutathione levels) system, indicating a direct effect of stress hormones in the induction of the brain oxidative damage. On the other hand, 4i and fluoxetine treatment reversed the CORT induced depressive-like deficits. Furthermore, 4i and fluoxetine prevented CORT induced oxidative brain insults, which may plausibly demonstrate one of the key mechanisms for antidepressant-like effects of the compounds. Thus, the study suggests that 5HT3 antagonist; 4i may be implicated as pharmacological intervention targeting depressive-like anomaly associated with HPA-axis dysregulation.
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Affiliation(s)
- Deepali Gupta
- Department of Pharmacy, Birla Institute of Technology & Science, Pilani, Rajasthan 333031, India.
| | - Mahesh Radhakrishnan
- Faculty Affairs and Professor, Department of Pharmacy, Birla Institute of Technology and Science, Pilani, Rajasthan 333031, India.
| | - Yeshwant Kurhe
- Department of Pharmacy, Birla Institute of Technology & Science, Pilani, Rajasthan 333031, India.
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16
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Holland RA, Leonard JJ, Kensey NA, Hannikainen PA, De Jonghe BC. Cisplatin induces neuronal activation and increases central AMPA and NMDA receptor subunit gene expression in mice. Physiol Behav 2014; 136:79-85. [PMID: 24582677 DOI: 10.1016/j.physbeh.2014.02.038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Revised: 02/17/2014] [Accepted: 02/23/2014] [Indexed: 10/25/2022]
Abstract
Although rats and mice do not vomit, these species are widely studied as models of energy balance and sickness behavior. Previous work has shown that rats exhibit similar neuroanatomical activation of brain and visceral afferent pathways following cisplatin chemotherapy compared to vomiting species. However, the neural response to cisplatin in mice is understudied. Here, food intake, body weight, and central c-Fos immunofluorescence were analyzed in the hindbrains of male C57BL/6 mice following IP saline or cisplatin (5mg/kg, and 20mg/kg doses). As glutamate receptor signaling is classically linked to inhibitory feeding pathways in the rodent, gene expression of selected α-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and N-methyl-d-aspartic acid (NMDA) receptor subunits were assessed in the dorsal vagal complex (DVC), parabrachial nucleus (PBN), amygdala, and bed nucleus of the stria terminalis (BNST). Our results show dose-dependent reductions in food intake and body weight following cisplatin treatment, as well as increases in cisplatin-induced c-Fos in the PBN and throughout the DVC. Quantitative PCR analysis shows cisplatin-induced increases in NMDA receptor subunit expression, particularly NR2B, in the DVC, PBN, BNST, and amygdala. In addition, upregulation of AMPA receptor subunits (GluA1 and/or GluA2) were observed in all regions examined except the amygdala. Taken together, these results suggest similar neural pathways mediating cisplatin effects in mice compared to other well-studied species, which are likely mediated by central upregulation of AMPA and NMDA receptors.
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Affiliation(s)
- Ruby A Holland
- Dept. of Biobehavioral Health Sciences School of Nursing, University of Pennsylvania, Philadelphia, PA, 19104, United States
| | - John J Leonard
- Dept. of Biobehavioral Health Sciences School of Nursing, University of Pennsylvania, Philadelphia, PA, 19104, United States
| | - Nicholas A Kensey
- Dept. of Biobehavioral Health Sciences School of Nursing, University of Pennsylvania, Philadelphia, PA, 19104, United States
| | - Paavali A Hannikainen
- Dept. of Biobehavioral Health Sciences School of Nursing, University of Pennsylvania, Philadelphia, PA, 19104, United States
| | - Bart C De Jonghe
- Dept. of Biobehavioral Health Sciences School of Nursing, University of Pennsylvania, Philadelphia, PA, 19104, United States.
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17
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Fukuda T, Hirai Y, Maezawa H, Kitagawa Y, Funahashi M. Electrophysiologically identified presynaptic mechanisms underlying amylinergic modulation of area postrema neuronal excitability in rat brain slices. Brain Res 2013; 1494:9-16. [DOI: 10.1016/j.brainres.2012.11.051] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 11/28/2012] [Accepted: 11/29/2012] [Indexed: 11/30/2022]
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18
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Serotonin activates catecholamine neurons in the solitary tract nucleus by increasing spontaneous glutamate inputs. J Neurosci 2013; 32:16530-8. [PMID: 23152635 DOI: 10.1523/jneurosci.1372-12.2012] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Serotonin (5-HT) is a critical neurotransmitter in the control of autonomic functions. 5-HT(3) receptors participate in vagal afferent feedback to decrease food intake and regulate cardiovascular reflexes; however, the phenotype of the solitary tract nucleus (NTS) neurons involved is not known. A(2)/C(2) catecholamine (CA) neurons in the NTS are directly activated by visceral afferents and are important for the control of food intake and cardiovascular function, making them good candidates to respond to and mediate the effects of serotonin at the level of the NTS. This study examines serotonin's effects on NTS-CA neurons using patch-clamp techniques and transgenic mice expressing an enhanced green fluorescent protein driven by the tyrosine hydroxylase (TH) promoter (TH-EGFP) to identify catecholamine neurons. Serotonin increased the frequency of spontaneous glutamate excitatory postsynaptic currents (sEPSCs) in >90% of NTS-TH-EGFP neurons, an effect blocked by the 5-HT(3) receptor antagonist ondansetron and mimicked by the 5-HT(3) receptor agonists SR5227 and mCPBG. In contrast, 5-HT(3) receptor agonists increased sEPSCs on a minority (<30%) of non-TH neurons. 5-HT(3) receptor agonists increased the frequency, but not the amplitude, of mini-EPSCs, suggesting that their actions are presynaptic. 5-HT(3) receptor agonists increased the firing rate of TH-EGFP neurons, an effect dependent on the increased spontaneous glutamate inputs as it was blocked by the ionotropic glutamate antagonist NBQX, but independent of visceral afferent activation. These results demonstrate a cellular mechanism by which serotonin activates NTS-TH neurons and suggest a pathway by which it can increase catecholamine release in target regions to modulate food intake, motivation, stress, and cardiovascular function.
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Zendehdel M, Taati M, Jonaidi H, Amini E. The role of central 5-HT(2C) and NMDA receptors on LPS-induced feeding behavior in chickens. J Physiol Sci 2012; 62:413-9. [PMID: 22735975 PMCID: PMC10717554 DOI: 10.1007/s12576-012-0218-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2012] [Accepted: 06/04/2012] [Indexed: 11/25/2022]
Abstract
In mammals, LPS regulate feeding primarily through the 5-HT(1A) and 5-HT(2c) receptors within the brain. However, the central effect of 5-HT(1A) and 5-HT(2c) on LPS-induced feeding behavior has not been studied in non-mammalian species. Also, the role of glutamatergic system in LPS-induced anorexia has never been examined in either mammalian or non-mammalian species. Therefore, in this study, we examined the role of serotonergic and glutamatergic systems on LPS-induced anorexia in chickens. Food intake was measured in chickens after centrally administered lipopolysaccharide (LPS) (20 ng) (0 h), followed by intracerebroventricular (ICV) injection of the 5-HT(1A) autoreceptor agonist (8-OH-DPAT, 61 nmol), 5-HT(2c) receptor antagonist (SB 242084, 30 nm), and NMDA receptor antagonist (DL-AP5, 5 nm) at the onset of anorexia (4 h). In the following experiments, we used DL-AP5 before 5-HT (10 μg) and SB242084 before glutamate (300 nm) for evaluation of the interaction between 5-HTergic and glutamatergic systems on food intake. The results of this study showed that SB 242084 and DL-AP5 significantly attenuated food intake reduction caused by LPS (P < 0.05) but 8-OH-DPAT had no effect. In addition, 5-HT-induced anorexia was significantly attenuated by DL-AP5 pretreatment (P < 0.05), while SB 242084 had no effect on glutamate-induced hypophagia. These results indicated that 5-HT and glutamate (via 5-HT(2c) and NMDA receptor, respectively) dependently regulate LPS-induced hypophagia in chickens.
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Affiliation(s)
- Morteza Zendehdel
- Department of Physiology, Faculty of Veterinary Medicine, University of Tehran, 14155-6453, Tehran, Iran.
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Shinpo K, Hirai Y, Maezawa H, Totsuka Y, Funahashi M. The role of area postrema neurons expressing H-channels in the induction mechanism of nausea and vomiting. Physiol Behav 2012; 107:98-103. [PMID: 22722099 DOI: 10.1016/j.physbeh.2012.06.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2012] [Revised: 05/24/2012] [Accepted: 06/03/2012] [Indexed: 01/28/2023]
Abstract
The area postrema is one of the circumventricular organs, lacks a blood-brain barrier, and is well known as the chemoreceptor trigger zone for emesis. Area postrema neurons are sensitive to emetic chemical substances carried in the blood plasma. Our previous study demonstrated the presence of 3 types of neurons characterized by different ion channels expressed in each cell type, but the type or types of area postrema neurons involved in the induction of nausea and/or emesis have remained unclear. To clarify the role of the most populous cells, which express the hyperpolarization-activated cation channel (H-channel), in induction of nausea and/or emesis, we investigated the effects of ZD7288 (an H-channel inhibitor) on apomorphine-induced conditioned taste aversion (CTA) to saccharin and c-Fos expression in the area postrema. We found that ZD7288 inhibited the acquisition of CTA and reduced apomorphine-induced c-Fos expression in the area postrema, indicating the involvement of the cells expressing H-channels in the induction of nausea and/or emesis. Finally, we discuss the role of cells expressing H-channels in the mechanism of nausea and/or vomiting.
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Affiliation(s)
- Keisuke Shinpo
- Department of Oral and Maxillofacial Surgery, Graduate School of Dental Medicine, Hokkaido University, Kita 13, Nishi 7, Kita-ku, Sapporo 060-8586, Japan.
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Role of peripheral and spinal 5-HT3 receptors in development and maintenance of formalin-induced long-term secondary allodynia and hyperalgesia. Pharmacol Biochem Behav 2012; 101:246-57. [DOI: 10.1016/j.pbb.2012.01.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 01/13/2012] [Accepted: 01/16/2012] [Indexed: 12/19/2022]
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Blockade of the NMDA and AMPA/kainate receptors in the dorsal raphe nucleus prevents the 5-HT₃ receptor agonist m-chlorophenylbiguanide-induced suppression of REM sleep in the rat. Prog Neuropsychopharmacol Biol Psychiatry 2011; 35:1341-8. [PMID: 21514352 DOI: 10.1016/j.pnpbp.2011.04.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2011] [Revised: 04/01/2011] [Accepted: 04/05/2011] [Indexed: 11/22/2022]
Abstract
The effects of the selective 5-HT(3) receptor agonist m-chlorophenylbiguanide (m-CPBG), and of the NMDA (N-methyl-D-aspartate) and AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionate)/kainate antagonists AP-5 [(±)-2-amino-5-phosphono-pentanoic acid] and CNQX (6-cyano-7-nitroquinoxaline-2,3-dione), respectively, were studied in adult male Wistar rats implanted for chronic sleep recordings. The compounds were microinjected directly into the dorsal raphe nucleus (DRN) during the light period of the 12-h light/12-h dark cycle. Infusion of m-CPBG (2 and 4mM) into the DRN induced a significant reduction of rapid-eye-movement sleep (REMS) and of the number of REM periods. Local infusion of AP-5 (0.5-1 mM) and CNQX (2 mM) significantly increased slow wave sleep (SWS). Pretreatment with AP-5 (0.5 mM) or CNQX (0.5 mM) antagonized the m-CPBG-induced suppression of REMS. It is proposed that the reduction of REMS after microinjection of m-CPBG into de DRN is related to the activation of glutamatergic interneurons that express the 5-HT(3) receptor and make synaptic contacts with serotonergic cells. The resultant increase of serotonin release at postsynaptic sites involved in the induction of REMS would provoke the suppression of the behavioral state. Our findings provide, in addition, new details concerning the pharmacology of DRN serotonergic neurons in the rat that may become relevant to the development of drugs for enhancing cortical and subcortical serotonergic neurotransmission.
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Abstract
Serotonin (5-HT)3 receptors are the only ligand-gated ion channel of the 5-HT receptors family. They are present both in the peripheral and central nervous system and are localized in several areas involved in mood regulation (e.g., hippocampus or prefrontal cortex). Moreover, they are involved in regulation of neurotransmitter systems implicated in the pathophysiology of major depression (e.g., dopamine or GABA). Clinical and preclinical studies have suggested that 5-HT3 receptors may be a relevant target in the treatment of affective disorders. 5-HT3 receptor agonists seem to counteract the effects of antidepressants in non-clinical models, whereas 5-HT3 receptor antagonists, such as ondansetron, present antidepressant-like activities. In addition, several antidepressants, such as mirtazapine, also target 5-HT3 receptors. In this review, we will report major advances in the research of 5-HT3 receptor's roles in neuropsychiatric disorders, with special emphasis on mood and anxiety disorders.
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Monti JM. Serotonin control of sleep-wake behavior. Sleep Med Rev 2011; 15:269-81. [PMID: 21459634 DOI: 10.1016/j.smrv.2010.11.003] [Citation(s) in RCA: 343] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2010] [Revised: 11/27/2010] [Accepted: 11/28/2010] [Indexed: 11/19/2022]
Abstract
Based on electrophysiological, neurochemical, genetic and neuropharmacological approaches, it is currently accepted that serotonin (5-HT) functions predominantly to promote wakefulness (W) and to inhibit REM (rapid eye movement) sleep (REMS). Yet, under certain circumstances the neurotransmitter contributes to the increase in sleep propensity. Most of the serotonergic innervation of the cerebral cortex, amygdala, basal forebrain (BFB), thalamus, preoptic and hypothalamic areas, raphe nuclei, locus coeruleus and pontine reticular formation comes from the dorsal raphe nucleus (DRN). The 5-HT receptors can be classified into at least seven classes, designated 5-HT(1-7). The 5-HT(1A) and 5-HT(1B) receptor subtypes are linked to the inhibition of adenylate cyclase, and their activation evokes a membrane hyperpolarization. The actions of the 5-HT(2A), 5-HT(2B) and 5-HT(2C) receptor subtypes are mediated by the activation of phospholipase C, with a resulting depolarization of the host cell. The 5-HT(3) receptor directly activates a 5-HT-gated cation channel which leads to the depolarization of monoaminergic, aminoacidergic and cholinergic cells. The primary signal transduction pathway of 5-HT(6) and 5-HT(7) receptors is the stimulation of adenylate cyclase which results in the depolarization of the follower neurons. Mutant mice that do not express 5-HT(1A) or 5-HT(1B) receptor exhibit greater amounts of REMS than their wild-type counterparts, which could be related to the absence of a postsynaptic inhibitory effect on REM-on neurons of the laterodorsal and pedunculopontine tegmental nuclei (LDT/PPT). 5-HT(2A) and 5-HT(2C) receptor knock-out mice show a significant increase of W and a reduction of slow wave sleep (SWS) which has been ascribed to the increase of catecholaminergic neurotransmission involving mainly the noradrenergic and dopaminergic systems. Sleep variables have been characterized, in addition, in 5-HT(7) receptor knock-out mice; the mutants spend less time in REMS that their wild-type counterparts. Direct infusion of the 5-HT(1A) receptor agonists 8-OH-DPAT and flesinoxan into the DRN significantly enhances REMS in the rat. In contrast, microinjection of the 5-HT(1B) (CP-94253), 5-HT(2A/2C) (DOI), 5-HT(3) (m-chlorophenylbiguanide) and 5-HT(7) (LP-44) receptor agonists into the DRN induces a significant reduction of REMS. Systemic injection of full agonists at postsynaptic 5-HT(1A) (8-OH-DPAT, flesinoxan), 5-HT(1B) (CGS 12066B, CP-94235), 5-HT(2C) (RO 60-0175), 5-HT(2A/2C) (DOI, DOM), 5-HT(3) (m-chlorophenylbiguanide) and 5-HT(7) (LP-211) receptors increases W and reduces SWS and REMS. Of note, systemic administration of the 5-HT(2A/2C) receptor antagonists ritanserin, ketanserin, ICI-170,809 or sertindole at the beginning of the light period has been shown to induce a significant increase of SWS and a reduction of REMS in the rat. Wakefulness was also diminished in most of these studies. Similar effects have been described following the injection of the selective 5-HT(2A) receptor antagonists volinanserin and pruvanserin and of the 5-HT(2A) receptor inverse agonist nelotanserin in rodents. In addition, the effects of these compounds have been studied on the sleep electroencephalogram of subjects with normal sleep. Their administration was followed by an increase of SWS and, in most instances, a reduction of REMS. The administration of ritanserin to poor sleepers, patients with chronic primary insomnia and psychiatric patients with a generalized anxiety disorder or a mood disorder caused a significant increase in SWS. The 5-HT(2A) receptor inverse agonist APD-125 induced also an increase of SWS in patients with chronic primary insomnia. It is known that during the administration of benzodiazepine (BZD) hypnotics to patients with insomnia there is a further reduction of SWS and REMS, whereas both variables tend to remain decreased during the use of non-BZD derivatives (zolpidem, zopiclone, eszopiclone, zaleplon). Thus, the association of 5-HT(2A) antagonists or 5-HT(2A) inverse agonists with BZD and non-BZD hypnotics could be a valid alternative to normalize SWS in patients with primary or comorbid insomnia.
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Affiliation(s)
- Jaime M Monti
- Department of Pharmacology and Therapeutics, School of Medicine Clinics Hospital, Montevideo 11600, Uruguay.
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Ohno Y, Imaki J, Mae Y, Takahashi T, Tatara A. Serotonergic modulation of extrapyramidal motor disorders in mice and rats: Role of striatal 5-HT3 and 5-HT6 receptors. Neuropharmacology 2011; 60:201-8. [DOI: 10.1016/j.neuropharm.2010.08.019] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2010] [Revised: 08/23/2010] [Accepted: 08/23/2010] [Indexed: 11/25/2022]
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Shuto T, Nishi A. Treatment of the psychostimulant-sensitized animal model of schizophrenia. CNS Neurosci Ther 2010; 17:133-9. [PMID: 21159151 DOI: 10.1111/j.1755-5949.2010.00218.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Behavioral sensitization to psychostimulants in rodents is associated with the alteration of dopaminergic neurotransmission, and has been proposed as a useful model of schizophrenia due to its progressively intensifying, easily relapsing, and long-lasting features. Pharmacological treatments that reverse the established sensitization may have potential therapeutic values for schizophrenia. The present aim is to review pharmacological treatments that induce the reversal of established sensitization to psychostimulants. In addition, we discuss possible mechanisms for the reversal of sensitization. Reversal of sensitization is induced by chronic dopamine D1 receptor agonism, D2 or D1/D2 receptor agonism combined with mild N-methyl-D-aspartate (NMDA) receptor antagonism or serotonin (5-HT(2A) or 5-HT(3) ) receptor antagonism, 5-HT(1A) receptor agonism, and 5-HT(2A) or 5-HT(3) receptor antagonism. Chronic treatments with these drugs likely adjust altered dopaminergic neurotransmission in sensitized animals. Especially, chronic dopamine D1 receptor agonism, which may adjust mesolimbic hyperdopaminergic and mesocortical hypodopaminergic functions in sensitized animals, is an attractive therapeutic approach for schizophrenia.
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Affiliation(s)
- Takahide Shuto
- Department of Pharmacology, Kurume University School of Medicine, Kurume, Fukuoka, Japan.
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Gatt JM, Nemeroff CB, Schofield PR, Paul RH, Clark CR, Gordon E, Williams LM. Early life stress combined with serotonin 3A receptor and brain-derived neurotrophic factor valine 66 to methionine genotypes impacts emotional brain and arousal correlates of risk for depression. Biol Psychiatry 2010; 68:818-24. [PMID: 20728877 DOI: 10.1016/j.biopsych.2010.06.025] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Revised: 05/28/2010] [Accepted: 06/24/2010] [Indexed: 12/25/2022]
Abstract
BACKGROUND Depression will be the second largest burden of disease by 2020. Developing new tools for identifying risk and ultimately prevention of depression relies on elucidating the integrative relationships between susceptibility markers from gene-stress interactions and how they impact emotional brain and arousal systems. They have largely been studied in isolation. METHODS We examined how genetic (brain-derived neurotrophic factor [BDNF] valine 66 to methionine [Val66Met] and serotonin receptor gene 3A [HTR3A]) and early life stress susceptibility factors interact in predicting electroencephalogram (EEG) asymmetry, emotion-elicited heart rate, and self-reported negativity bias, each correlates of risk for depression. Caucasian volunteers (n = 363) were derived from the Brain Resource International Database, via the Brain Research And Integrative Neuroscience Network. RESULTS Individuals with both BDNF methionine and HTR3A CC risk genotypes and early life stressors demonstrated a profile of elevated emotion-elicited heart rate and right frontal hyper-activation with right parietotemporal hypoactivation in EEG asymmetry. Elevations in heart rate were a moderator of negativity bias. CONCLUSIONS The findings provide new evidence that these gene-stress susceptibility factors contribute to a brain-arousal profile indicative of risk for depression. They are a step toward identifying biological markers for detecting risk before overt symptoms. It would be valuable for future studies to examine comorbidity and specificity issues; for instance, whether these gene-stress factors contribute in different ways to the partially distinct EEG asymmetry profiles found with anxiety.
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Affiliation(s)
- Justine M Gatt
- Brain Dynamics Center, University of Sydney Medical School and Westmead Millennium Institute, Australia
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The role of dorsal raphe nucleus serotonergic and non-serotonergic neurons, and of their receptors, in regulating waking and rapid eye movement (REM) sleep. Sleep Med Rev 2010; 14:319-27. [PMID: 20153670 DOI: 10.1016/j.smrv.2009.10.003] [Citation(s) in RCA: 98] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2009] [Revised: 10/12/2009] [Accepted: 10/12/2009] [Indexed: 11/22/2022]
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29
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Carrillo M, Ricci LA, Schwartzer JJ, Melloni RH. Immunohistochemical characterization of 5-HT3A receptors in the Syrian hamster forebrain. Brain Res 2010; 1329:67-81. [DOI: 10.1016/j.brainres.2010.02.038] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2009] [Revised: 02/04/2010] [Accepted: 02/09/2010] [Indexed: 12/24/2022]
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30
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Cuesta M, Clesse D, Pévet P, Challet E. New light on the serotonergic paradox in the rat circadian system. J Neurochem 2009; 110:231-43. [PMID: 19457131 DOI: 10.1111/j.1471-4159.2009.06128.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The main mammalian circadian clock, localized in the suprachiasmatic nuclei can be synchronized not only with light, but also with serotonergic activation. Serotonergic agonists and serotonin reuptake inhibitors (e.g., fluoxetine) have a non-photic influence (shifting effects during daytime and attenuation of photic resetting during nighttime) on hamsters' and mice' main clock. Surprisingly, in rats serotonergic modulation of the clock shows essentially photic-like features in vivo (shifting effects during nighttime). To delineate this apparent paradox, we analyzed the effects of fluoxetine and serotonin agonists on rats' clock. First, fluoxetine induced behavioral phase-advances associated with down-regulated expression of the clock genes Per1 and Rorbeta and up-regulated expression of Rev-erbalpha during daytime. Moreover, fluoxetine produced an attenuation of light-induced phase-advances in association with altered expression of Per1, Per2 and Rorbeta during nighttime. Second, we showed that 5-HT(1A) receptors -maybe with co-activation of 5-HT(7) receptors- were implicated in non-photic effects on the main clock. By contrast, 5-HT(3) and 5-HT(2C) receptors were involved in photic-like effects and, for 5-HT(2C) subtype only, in potentiation of photic resetting. Thus this study demonstrates that as for other nocturnal rodents, a global activation of the serotonergic system induces non-photic effects in the rats' clock during daytime and nighttime.
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Affiliation(s)
- Marc Cuesta
- Département de Neurobiologie des Rythmes, Institut de Neurosciences Cellulaires et Intégratives, UPR3212, Centre National de la Recherche Scientifique, Université de Strasbourg, Strasbourg, France
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31
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Lechin F, van der Dijs B. Central nervous system plus autonomic nervous system disorders responsible for gastrointestinal and pancreatobiliary diseases. Dig Dis Sci 2009; 54:458-70. [PMID: 18629642 DOI: 10.1007/s10620-008-0369-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/04/2008] [Accepted: 06/03/2008] [Indexed: 12/09/2022]
Abstract
Clinical digestive disorders depend on the non-adequate coupling of functioning of the gastrointestinal tract with that of its affluent systems, namely, the pancreatic exocrine and the hepato-biliary secretions. The secretion of gastrointestinal hormones is monitored by the peripheral autonomic nervous system. However, the latter is regulated by the central nervous system (CNS) circuitry localized at the medullary pontine segment of the CNS. In turn, both parasympathetic and adrenergic medullary circuitries are regulated by the pontine A5 noradrenergic (NA) and the dorsal raphe serotonergic nuclei, respectively. DR-5HT is positively correlated with the C1-Ad medullary nuclei (responsible for adrenal gland secretion), whereas the MR-5HT nucleus is positively correlated with the A5-NA pontomedullary nucleus. The latter is responsible for neural sympathetic activity (sympathetic nerves). Both types of sympathetic activities maintain an alternation with the peripheral parasympathetic branch, which is positively correlated with the enterochromaffin cells that secrete serotonin. Serotonin displays hormonal antagonism to the circulating catecholamines.
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Affiliation(s)
- Fuad Lechin
- Department of Neurophysiology, Instituto de Medicina Experimental, Faculty of Medicine, Universidad Central de Venezuela, Apartado 80.983, Caracas, 1080, Venezuela.
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32
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Barnes NM, Hales TG, Lummis SC, Peters JA. The 5-HT3 receptor--the relationship between structure and function. Neuropharmacology 2009; 56:273-84. [PMID: 18761359 PMCID: PMC6485434 DOI: 10.1016/j.neuropharm.2008.08.003] [Citation(s) in RCA: 174] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2008] [Revised: 07/31/2008] [Accepted: 08/01/2008] [Indexed: 12/15/2022]
Abstract
The 5-hydroxytryptamine type-3 (5-HT3) receptor is a cation-selective ion channel of the Cys-loop superfamily. 5-HT3 receptor activation in the central and peripheral nervous systems evokes neuronal excitation and neurotransmitter release. Here, we review the relationship between the structure and the function of the 5-HT3 receptor. 5-HT3A and 5-HT3B subunits are well established components of 5-HT3 receptors but additional HTR3C, HTR3D and HTR3E genes expand the potential for molecular diversity within the family. Studies upon the relationship between subunit structure and the ionic selectivity and single channel conductances of 5-HT3 receptors have identified a novel domain (the intracellular MA-stretch) that contributes to ion permeation and selectivity. Conventional and unnatural amino acid mutagenesis of the extracellular domain of the receptor has revealed residues, within the principle (A-C) and complementary (D-F) loops, which are crucial to ligand binding. An area requiring much further investigation is the subunit composition of 5-HT3 receptors that are endogenous to neurones, and their regional expression within the central nervous system. We conclude by describing recent studies that have identified numerous HTR3A and HTR3B gene polymorphisms that impact upon 5-HT3 receptor function, or expression, and consider their relevance to (patho)physiology.
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Affiliation(s)
- Nicholas M. Barnes
- Cellular and Molecular Neuropharmacology Research Group, Department of Pharmacology, Division of Neuroscience, The Medical School, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Tim G. Hales
- Department of Pharmacology and Physiology, The George Washington University, Washington, DC 20037, USA
| | - Sarah C.R. Lummis
- Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK
| | - John A. Peters
- Neurosciences Institute, Division of Pathology and Neuroscience, Ninewells Hospital and Medical School, The University of Dundee, Dundee DD1 9SY, UK
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Characterization of the effects of four HTR3B polymorphisms on human 5-HT3AB receptor expression and signalling. Pharmacogenet Genomics 2008; 18:1027-40. [DOI: 10.1097/fpc.0b013e328310f950] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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34
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Monti JM, Jantos H. Activation of the serotonin 5-HT3 receptor in the dorsal raphe nucleus suppresses REM sleep in the rat. Prog Neuropsychopharmacol Biol Psychiatry 2008; 32:940-7. [PMID: 18295951 DOI: 10.1016/j.pnpbp.2007.12.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/09/2007] [Revised: 12/19/2007] [Accepted: 12/26/2007] [Indexed: 11/24/2022]
Abstract
The effects of the selective 5-HT(3) receptor agonist and antagonist m-chlorophenylbiguanide (m-CPBG) and ondansetron, respectively, were studied in adult male Wistar rats implanted for chronic sleep recordings. Microinjection of m-CPBG (2.0 and 4.0 mM) into the dorsal raphe nucleus (DRN) decreased rapid-eye-movement sleep (REMS) and the number of REM periods during the first, second, and third 2-h recording period. On the other hand, direct infusion of ondansetron (0.5-1.0 mM) into the DRN induced no significant changes in sleep variables over the 6 h of recording. Pretreatment with ondansetron (0.5 mM) antagonized the m-CPBG (2.0 mM)-induced reduction of REMS and of the number of REM periods. The data are consistent with the hypothesis that the 5-HT(3) receptor is involved in the effect of DRN serotonergic neurons on brainstem structures that act to promote and induce REMS. It is suggested that the suppression of REMS after the microinjection of m-CPBG into the DRN is related, at least in part, to the stimulation of glutamatergic interneurons that express 5-HT(3) receptors. Activation of these receptors facilitates the release of glutamate, which, in turn, acts on postsynaptic N-methyl-d-aspartate and non-N-methyl-d-aspartate receptors expressed by serotonergic neurons of the DRN and increases the release of 5-HT at postsynaptic sites.
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Affiliation(s)
- Jaime M Monti
- Department of Pharmacology and Therapeutics, School of Medicine, Clinics Hospital, Montevideo 11300, Uruguay.
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35
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Kim KJ, Cho HS, Choi SJ, Jeun SH, Kim SY, Sung KW. Direct effects of riluzole on 5-hydroxytryptamine (5-HT)3 receptor-activated ion currents in NCB-20 neuroblastoma cells. J Pharmacol Sci 2008; 107:57-65. [PMID: 18460823 DOI: 10.1254/jphs.fp0072095] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
Abstract
The pharmacological action of riluzole, a drug that has been approved as a neuroprotective agent for the treatment of amyotrophic lateral sclerosis, has not yet been established. We examined the effects of riluzole on 5-hydroxytryptamine (5-HT)3) receptors in NCB-20 neuroblastoma cells using the whole-cell voltage clamp technique combined with a fast drug application method. Co-application of riluzole (1 - 300 microM, 5 s) produced a dose-dependent reduction in peak amplitudes and in the rise slope of the currents induced by 2 microM 5-HT. In addition, 5-HT3-mediated currents evoked by dopamine, a partial 5-HT3-receptor agonist, were inhibited by riluzole co-application. These inhibitory effects were clearly shown at low concentrations of 5-HT. The decay time constants of the receptor desensitization and deactivation were also significantly attenuated by riluzole. G-protein inhibitors (pertussis toxin and guanosine 5'-[beta-thio] diphosphate) did not completely block these inhibitory actions of riluzole. These results indicate that riluzole inhibits 5-HT3-induced ion currents directly by slowing channel activation in NCB-20 neuroblastoma cells.
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Affiliation(s)
- Ki Jung Kim
- Department of Pharmacology, Medical Research Center, College of Medicine, The Catholic University of Korea, Korea
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36
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High-frequency HTR3B variant associated with major depression dramatically augments the signaling of the human 5-HT3AB receptor. Proc Natl Acad Sci U S A 2008; 105:722-7. [PMID: 18184810 DOI: 10.1073/pnas.0708454105] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The 5-hydroxytryptamine-3 (5-HT3) receptor mediates the fast excitatory neurotransmission of serotonin and is known to mediate the nausea/emesis induced by radio/chemotherapy and anesthetics. A polymorphism encoding the variation Y129S in the 5-HT3B subunit exists in high frequency in the general population and has been shown to be inversely correlated to the incidence of major depression in women. We show that 5-HT3AB(Y129S) receptors exhibit a substantially increased maximal response to serotonin compared with WT receptors in two fluorescence-based cellular assays. In electrophysiological recordings, the deactivation and desensitization kinetics of the 5-HT3AB(Y129S) receptor are 20- and 10-fold slower, respectively, than those of the WT receptor. Single-channel measurements reveal a 7-fold-increased mean open time of 5-HT3AB(Y129S) receptors compared with WT receptors. The augmented signaling displayed by 5-HT3AB(Y129S) receptors may confer protection against the development of depression. The variant also may influence the development and/or treatment of nausea and other disorders involving 5-HT3 receptors. Thus, the impact of the high-frequency variant 5-HT3B(Y129S) on 5-HT3AB receptor signaling calls for a search for additional phenotypes, and the variant may thus aid in establishing the role of the 5-HT3AB receptor in pathophysiology.
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Abstract
The release of transmitters through vesicle exocytosis from nerve terminals is not constant but is subject to modulation by various mechanisms, including prior activity at the synapse and the presence of neurotransmitters or neuromodulators in the synapse. Instantaneous responses of postsynaptic cells to released transmitters are mediated by ionotropic receptors. In contrast to metabotropic receptors, ionotropic receptors mediate the actions of agonists in a transient manner within milliseconds to seconds. Nevertheless, transmitters can control vesicle exocytosis not only via slowly acting metabotropic, but also via fast acting ionotropic receptors located at the presynaptic nerve terminals. In fact, members of the following subfamilies of ionotropic receptors have been found to control transmitter release: ATP P2X, nicotinic acetylcholine, GABA(A), ionotropic glutamate, glycine, 5-HT(3), andvanilloid receptors. As these receptors display greatly diverging structural and functional features, a variety of different mechanisms are involved in the regulation of transmitter release via presynaptic ionotropic receptors. This text gives an overview of presynaptic ionotropic receptors and briefly summarizes the events involved in transmitter release to finally delineate the most important signaling mechanisms that mediate the effects of presynaptic ionotropic receptor activation. Finally, a few examples are presented to exemplify the physiological and pharmacological relevance of presynaptic ionotropic receptors.
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Affiliation(s)
- M M Dorostkar
- Institute of Experimental and Clinical Pharmacology, Medical University of Graz, Universitäts-platz 4, Graz, Austria
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38
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Chen L, Yung KKL, Chan YS, Yung WH. 5-HT excites globus pallidus neurons by multiple receptor mechanisms. Neuroscience 2007; 151:439-51. [PMID: 18082329 DOI: 10.1016/j.neuroscience.2007.11.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2007] [Revised: 10/31/2007] [Accepted: 11/30/2007] [Indexed: 11/26/2022]
Abstract
Anatomical and neurochemical studies indicated that the globus pallidus receives serotonergic innervation from raphe nuclei but the membrane effects of 5-HT on globus pallidus neurons are not entirely clear. We address this question by applying whole-cell patch-clamp recordings on globus pallidus neurons in immature rat brain slices. Under current-clamp recording, 5-HT depolarized globus pallidus neurons and increased their firing rate, an action blocked by both 5-HT(4) and 5-HT(7) receptor antagonists and attributable to an increase in cation conductance(s). Further experiments indicated that 5-HT enhanced the hyperpolarization-activated inward conductance which is blocked by 5-HT(7) receptor antagonist. To determine if 5-HT exerts any presynaptic effects on GABAergic and glutamatergic inputs, the actions of 5-HT on synaptic currents were studied. At 10 microM, 5-HT increased the frequency of spontaneous inhibitory postsynaptic currents (sIPSCs) but had no effect on both the frequency and amplitude of miniature inhibitory postsynaptic currents (mIPSCs). However, 5-HT at a higher concentration (50 microM) decreased the frequency but not the amplitude of the mIPSCs, indicating an inhibition of GABA release from the presynaptic terminals. This effect was sensitive to 5-HT(1B) receptor antagonist. In addition to the presynaptic effects on GABAergic neurotransmission, 5-HT at 50 microM had no consistent effects on glutamatergic neurotransmission, significantly increased the frequency of miniature excitatory postsynaptic currents (mEPSCs) in 4 of 11 neurons and decreased the frequency of mEPSCs in 3 of 11 neurons. In conclusion, we found that 5-HT could modulate the excitability of globus pallidus neurons by both pre- and post-synaptic mechanisms. In view of the extensive innervation by globus pallidus neurons on other basal ganglia nuclei, this action of 5-HT originated from the raphe may have a profound effect on the operation of the entire basal ganglia network.
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Affiliation(s)
- L Chen
- Department of Physiology, The Chinese University of Hong Kong, Shatin, Hong Kong, China
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Rüsch D, Braun HA, Wulf H, Schuster A, Raines DE. Inhibition of human 5-HT(3A) and 5-HT(3AB) receptors by etomidate, propofol and pentobarbital. Eur J Pharmacol 2007; 573:60-4. [PMID: 17669396 PMCID: PMC2276611 DOI: 10.1016/j.ejphar.2007.07.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2007] [Revised: 06/28/2007] [Accepted: 07/04/2007] [Indexed: 11/26/2022]
Abstract
The actions of intravenous anaesthetics on 5-HT(3AB) receptors have not been studied. Using oocyte electrophysiology, the effects of etomidate, propofol, and pentobarbital on human 5-HT(3A) and 5-HT(3AB) receptors were studied and compared. Inhibition of peak currents by all three compounds in both receptor subtypes was anaesthetic concentration-dependant and non-competitive. Because the half-maximal inhibitory concentrations for etomidate, propofol and pentobarbital in 5-HT(3A) and 5-HT(3AB) receptors were all above their respective anaesthetic concentrations, the results of our study suggest that neither 5-HT(3) receptor subtype contributes to the anaesthetic actions of etomidate, propofol or pentobarbital.
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Affiliation(s)
- Dirk Rüsch
- Department of Anaesthesia and Critical Care, University Hospital Giessen-Marburg GmbH, Marburg Campus, Baldingerstrasse, 35033 Marburg, Germany.
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Hodge CW, Bratt AM, Kelley SP. Deletion of the 5-HT(3A)-receptor subunit blunts the induction of cocaine sensitization. GENES BRAIN AND BEHAVIOR 2007; 7:96-102. [PMID: 17559417 PMCID: PMC2533739 DOI: 10.1111/j.1601-183x.2007.00332.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Serotonin (5-HT) receptors are classified into seven groups (5-HT(1-7)), comprising at least 14 structurally and pharmacologically distinct receptor subtypes. Pharmacological antagonism of ionotropic 5-HT(3) receptors has been shown to modulate both behavioral and neurochemical aspects of the induction of sensitization to cocaine. It is not known, however, if specific molecular subunits of the 5-HT(3) receptor influence the development of cocaine sensitization. To address this question, we studied the effects of acute and chronic intermittent cocaine administration in mice with a targeted deletion of the gene for the 5-HT(3A)-receptor subunit (5-HT(3A)-/-). 5-HT(3A) (-/-) mice showed blunted induction of cocaine-induced locomotor sensitization as compared with wild-type littermate controls. 5-HT(3A) (-/-) mice did not differ from wild-type littermate controls on measures of basal motor activity or response to acute cocaine treatment. Enhanced locomotor response to saline injection following cocaine sensitization was observed equally in 5-HT(3A) (-/-) and wild-type mice suggesting similar conditioned effects associated with chronic cocaine treatment. These data show a role for the 5-HT(3A)-receptor subunit in the induction of behavioral sensitization to cocaine and suggest that the 5-HT(3A) molecular subunit modulates neurobehavioral adaptations to cocaine, which may underlie aspects of addiction.
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Affiliation(s)
- C W Hodge
- Department of Psychiatry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
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Faerber L, Drechsler S, Ladenburger S, Gschaidmeier H, Fischer W. The neuronal 5-HT3 receptor network after 20 years of research — Evolving concepts in management of pain and inflammation. Eur J Pharmacol 2007; 560:1-8. [PMID: 17316606 DOI: 10.1016/j.ejphar.2007.01.028] [Citation(s) in RCA: 164] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2006] [Accepted: 01/09/2007] [Indexed: 11/19/2022]
Abstract
The 5-HT3 receptor is a pentameric ligand-gated cation channel which is found in the central and peripheral nervous system and on extraneuronal locations like lymphocytes, monocytes and fetal tissue. Five monomer subtypes, the 5-HT(3A-E) subunits, have been identified which show differences in the amino-terminal and the transmembrane region. The functional relevance of different receptor compositions is not yet clarified. 5-HT3 receptors are located predominantly in CNS regions that are involved in the integration of the vomiting reflex, pain processing, the reward system and anxiety control. The preferential localization on nerve endings is consistent with a physiological role of 5-HT3 receptors in the control of neurotransmitter release such as dopamine, cholecystokinin, glutamate, acetylcholine, GABA, substance P, or serotonin itself. 5-HT3-receptor agonists cause unpleasant effects like nausea and anxiety, and no clinical use has been considered. In contrast, the introduction of 5-HT3-receptor antagonists for chemotherapy-induced vomiting was extremely successful. After development of other gastrointestinal indications like postoperative vomiting and diarrhea-predominant irritable bowel syndrome recent research focuses on rheumatological indications such as fibromyalgia, rheumatoid arthritis and tendinopathies. Positive effects have also been observed for pain syndromes such as chronic neuropathic pain and migraine. These effects seem to be related to substance P-mediated inflammation and hyperalgesia. Furthermore, antiinflammatory and immunomodulatory properties have been observed for 5-HT3-receptor antagonists which might explain promising findings in systemic sclerosis and other immunological conditions. For all of these innovative indications the optimal dosing schedule is a crucial issue, since a bell-shaped dose-response curve has been observed repeatedly for 5-HT3-receptor antagonists, particularly in CNS effects.
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Affiliation(s)
- Lothar Faerber
- Department of Pharmacology, Regensburg Medical School, Universitaetsstr. 31, 93053 Regensburg, Germany.
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Graff C, Challet E, Pévet P, Wollnik F. 5-HT3 receptor-mediated photic-like responses of the circadian clock in the rat. Neuropharmacology 2007; 52:662-71. [PMID: 17084866 DOI: 10.1016/j.neuropharm.2006.09.016] [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] [Received: 12/02/2005] [Revised: 09/08/2006] [Accepted: 09/20/2006] [Indexed: 11/30/2022]
Abstract
Serotonin (5-HT) and 5-HT agonists have various resetting effects on the master clock, located in the suprachiasmatic nucleus (SCN), depending on the species. In rats, they induce photic-like effects on both locomotor activity rhythms and gene expression in the SCN. The 5-HT receptor(s) mediating these effects at circadian time 22 are localized in the SCN, most likely at a presynaptic level, on the retinohypothalamic terminals (RHT) known to convey photic information by releasing glutamate. Indeed, RHT degeneration blocks photic-like effects of a non-specific 5-HT agonist, quipazine. However, the 5-HT receptor subtype(s) involved is still unknown, although 5-HT(3) receptor activation is known to induce glutamate release. We thus analyzed the effects of selective 5-HT(3) agonist and antagonist, as well as a specific NMDA receptor antagonist, on different parameters of the clock. This study shows that the 5-HT(3) receptor mediates the resetting effects of quipazine on locomotor activity rhythms. The 5-HT(3) receptor is only partially implicated in quipazine-induced expression of c-FOS, while NMDA receptor inhibition blocks quipazine photic-like effects on both parameters. Taken together, photic-like responses produced by 5-HT stimulation in rats are likely mediated by (presynaptic?) 5-HT(3) receptor activation followed by NMDA receptor activation.
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Affiliation(s)
- Caroline Graff
- Department of Animal Physiology, Institute of Biology, University of Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany.
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Kawa K. Inhibitory synaptic transmission in area postrema neurons of the rat showing robust presynaptic facilitation mediated by nicotinic ACh receptors. Brain Res 2007; 1130:83-94. [PMID: 17166488 DOI: 10.1016/j.brainres.2006.10.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2006] [Revised: 08/25/2006] [Accepted: 10/02/2006] [Indexed: 02/05/2023]
Abstract
Inhibitory synaptic transmission and its modulation in neurons of the area postrema (AP), one of autonomic nuclei in the medulla, were studied using whole-cell patch-electrodes applied to slices from rats on postnatal days 10-24. When glycine (100 microM) or GABA (10 microM) was applied to AP neurons from a "Y tube", large outward currents that showed reversal potential of - 67 mV (approximate Cl- equilibrium potential estimated) were induced. At a holding potential of - 10 mV, application of high K+ to the AP neurons evoked massive inhibitory postsynaptic currents (IPSCs) in the neurons. Most of the evoked synaptic currents were blocked by bicuculline, while the remaining currents were sensitive to strychnine, indicating that the major inhibitory transmission in the area postrema was GABAergic. When nicotine (5-100 microM) was applied to AP neurons, robust IPSCs having GABAergic identity were evoked. Even in the presence of tetrodotoxin, nicotine could induce GABAergic IPSCs, most of which, however, disappeared in the presence of 5 mM Mg2+. Presynaptic facilitation was also induced by other nicotinic agonists, including cytisine, 1,1-dimethyl-4-phenyl-piperazinium iodide, ACh and choline. The nicotine-induced presynaptic facilitation was inhibited by mecamylamine and slightly inhibited by dihydro-beta-erythroidine or alpha-Bungarotoxin. These results indicate that nicotinic receptors are expressed at GABAergic presynaptic terminals in the area postrema and induce Ca2+ influx to trigger vesicular release. The major nicotinic receptors involved are thought to be heteromeric subtypes such as alpha3beta4 receptors, which may regulate inhibitory transmission potently responding to endogenous or exogenous nicotinic agents appeared in this area.
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Affiliation(s)
- Kazuyoshi Kawa
- Department of Neurophysiology, Tohoku University Graduate School of Medicine, 2-1, Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan.
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Ciranna L. Serotonin as a modulator of glutamate- and GABA-mediated neurotransmission: implications in physiological functions and in pathology. Curr Neuropharmacol 2006; 4:101-14. [PMID: 18615128 PMCID: PMC2430669 DOI: 10.2174/157015906776359540] [Citation(s) in RCA: 210] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2005] [Revised: 11/29/2005] [Accepted: 12/07/2005] [Indexed: 02/08/2023] Open
Abstract
The neurotransmitter serotonin (5-HT), widely distributed in the central nervous system (CNS), is involved in a large variety of physiological functions. In several brain regions 5-HT is diffusely released by volume transmission and behaves as a neuromodulator rather than as a "classical" neurotransmitter. In some cases 5-HT is co-localized in the same nerve terminal with other neurotransmitters and reciprocal interactions take place. This review will focus on the modulatory action of 5-HT on the effects of glutamate and gamma-amino-butyric acid (GABA), which are the principal neurotransmitters mediating respectively excitatory and inhibitory signals in the CNS. Examples of interaction at pre-and/or post-synaptic levels will be illustrated, as well as the receptors involved and their mechanisms of action. Finally, the physiological meaning of neuromodulatory effects of 5-HT will be briefly discussed with respect to pathologies deriving from malfunctioning of serotonin system.
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Affiliation(s)
- L Ciranna
- Dipartimento di Scienze Fisiologiche, Università di Catania, 6, Viale Andrea Doria, 95125 Catania, Italy.
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Funahashi M, Mitoh Y, Akaike T, Matsuo R. Variety of morphological and electrophysiological properties of area postrema neurons in adult rat brain slices. Neurosci Res 2006; 54:43-8. [PMID: 16293330 DOI: 10.1016/j.neures.2005.10.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2005] [Revised: 10/06/2005] [Accepted: 10/11/2005] [Indexed: 12/27/2022]
Abstract
Whole-cell recordings were performed to examine the morphological properties of electrophysiologically classified area postrema (AP) neurons in rat brain slices. Using electrophysiological criteria, AP neurons were subdivided into three groups: (1) cells displaying both the hyperpolarization-activated cation current (I(h)) and the fast transient outward current (fast I(to)); (2) cells displaying only the fast I(to); (3) cells displaying only the slow I(to). All AP neurons had a single axon that was distinctly thinner than the cells' dendrites. No systematic differences, across groups, in the orientation of dendrites or axons were identified. Mean values of cell size and capacitance of neurons from group 3 were significantly larger than those of the other groups. Interestingly, a number of cells from groups 1 and 3 but not group 2 were found to extend their dendrites into the nucleus tractus solitarius (NTS), suggesting that AP neurons could receive vagal afferent inputs at their dendritic termini within the NTS. Although the AP has been implicated to contain uniformly shaped neurons, this study indicates the presence of significantly different subpopulations of AP neurons, which were characterized not only electrophysiologically but also morphologically.
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Affiliation(s)
- Makoto Funahashi
- Department of Oral Physiology and Cellular Function, Hokkaido University, Graduate School of Dental Medicine, North 13 West 7 Kita-ku, Sapporo 060-8586, Japan.
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