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Kim H, Park KT, Jo H, Shin Y, Chung G, Ko SG, Jin YH, Kim W. The effect of ginger extract on cisplatin-induced acute anorexia in rats. Front Pharmacol 2023; 14:1267254. [PMID: 38026983 PMCID: PMC10665510 DOI: 10.3389/fphar.2023.1267254] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Accepted: 10/30/2023] [Indexed: 12/01/2023] Open
Abstract
Cisplatin is a platinum-based chemotherapeutic agent widely used to treat various cancers. However, several side effects have been reported in treated patients. Among these, acute anorexia is one of the most severe secondary effects. In this study, a single oral administration of 100 or 500 mg/kg ginger extract (GE) significantly alleviated the cisplatin-induced decrease in food intake in rats. However, these body weight and water intake decreases were reversed in the 100 mg/kg group rats. To elucidate the underlying mechanism of action, serotonin (5-HT) and 5-HT2C, 3A, and 4 receptors in the nodose ganglion of the vagus nerve were investigated. The results showed that cisplatin-induced increases in serotonin levels in both the blood and nodose ganglion tissues were significantly decreased by100 and 500 mg/kg of GE administration. On 5-HT receptors, 5-HT3A and 4, but not 2C receptors, were affected by cisplatin, and GE 100 and 500 mg/kg succeeded in downregulating the evoked upregulated gene of these receptors. Protein expression of 5-HT3A and 4 receptors were also reduced in the 100 mg/kg group. Furthermore, the injection of 5-HT3A, and 4 receptors antagonists (palonostron, 0.1 mg/kg, i.p.; piboserod, 1 mg/kg, i.p., respectively) in cisplatin treated rats prevented the decrease in food intake. Using high-performance liquid chromatography (HPLC) analysis, [6]-gingerol and [6]-shogaol were identified and quantified as the major components of GE, comprising 4.12% and 2.15% of the GE, respectively. Although [6]-gingerol or [6]-shogaol alone failed to alleviate the evoked anorexia, when treated together, the effect was significant on the cisplatin-induced decrease in food intake. These results show that GE can be considered a treatment option to alleviate cisplatin-induced anorexia.
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Affiliation(s)
- Hyeonah Kim
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Keun-Tae Park
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Heejoon Jo
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Yuchan Shin
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Geehoon Chung
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Seong-Gyu Ko
- Korean Medicine-Based Drug Repositioning Cancer Research Center, College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Young-Ho Jin
- Department of Physiology, College of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Woojin Kim
- Department of Physiology, College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea
- Korean Medicine-Based Drug Repositioning Cancer Research Center, College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea
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Gut bacteria-derived 5-hydroxyindole is a potent stimulant of intestinal motility via its action on L-type calcium channels. PLoS Biol 2021; 19:e3001070. [PMID: 33481771 PMCID: PMC7857600 DOI: 10.1371/journal.pbio.3001070] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 02/03/2021] [Accepted: 12/29/2020] [Indexed: 12/24/2022] Open
Abstract
Microbial conversion of dietary or drug substrates into small bioactive molecules represents a regulatory mechanism by which the gut microbiota alters intestinal physiology. Here, we show that a wide variety of gut bacteria can metabolize the dietary supplement and antidepressant 5-hydroxytryptophan (5-HTP) to 5-hydroxyindole (5-HI) via the tryptophanase (TnaA) enzyme. Oral administration of 5-HTP results in detection of 5-HI in fecal samples of healthy volunteers with interindividual variation. The production of 5-HI is inhibited upon pH reduction in in vitro studies. When administered orally in rats, 5-HI significantly accelerates the total gut transit time (TGTT). Deciphering the underlying mechanisms of action reveals that 5-HI accelerates gut contractility via activation of L-type calcium channels located on the colonic smooth muscle cells. Moreover, 5-HI stimulation of a cell line model of intestinal enterochromaffin cells results in significant increase in serotonin production. Together, our findings support a role for bacterial metabolism in altering gut motility and lay the foundation for microbiota-targeted interventions.
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Abe T, Kosaka Y, Kawasaki T, Ohata Y, Yamashiro T, Yamada K. Revisiting 2-Alkoxy-3-bromoindolines: Control C-2 vs. C-3 Elimination for Regioselective Synthesis of Alkoxyindoles. Chem Pharm Bull (Tokyo) 2020; 68:555-558. [DOI: 10.1248/cpb.c20-00135] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Takumi Abe
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido
| | - Yuta Kosaka
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido
| | - Takaaki Kawasaki
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido
| | - Yuki Ohata
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido
| | - Toshiki Yamashiro
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido
| | - Koji Yamada
- Faculty of Pharmaceutical Sciences, Health Sciences University of Hokkaido
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Luqman A, Ebner P, Reichert S, Sass P, Kabagema-Bilan C, Heilmann C, Ruth P, Götz F. A new host cell internalisation pathway for SadA-expressing staphylococci triggered by excreted neurochemicals. Cell Microbiol 2019; 21:e13044. [PMID: 31099148 PMCID: PMC6771854 DOI: 10.1111/cmi.13044] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Revised: 04/23/2019] [Accepted: 05/08/2019] [Indexed: 12/17/2022]
Abstract
Staphylococcus aureus is a facultative intracellular pathogen that invades a wide range of professional and nonprofessional phagocytes by triggering internalisation by interaction of surface‐bound adhesins with corresponding host cell receptors. Here, we identified a new concept of host cell internalisation in animal‐pathogenic staphylococcal species. This new mechanism exemplified by Staphylococcus pseudintermedius ED99 is not based on surface‐bound adhesins but is due to excreted small neurochemical compounds, such as trace amines (TAs), dopamine (DOP), and serotonin (SER), that render host cells competent for bacterial internalisation. The neurochemicals are produced by only one enzyme, the staphylococcal aromatic amino acid decarboxylase (SadA). Here, we unravelled the mechanism of how neurochemicals trigger internalisation into the human colon cell line HT‐29. We found that TAs and DOP are agonists of the α2‐adrenergic receptor, which, when activated, induces a cascade of reactions involving a decrease in the cytoplasmic cAMP level and an increase in F‐actin formation. The signalling cascade of SER follows a different pathway. SER interacts with 5HT receptors that trigger F‐actin formation without decreasing the cytoplasmic cAMP level. The neurochemical‐induced internalisation in host cells is independent of the fibronectin‐binding protein pathway and has an additive effect. In a sadA deletion mutant, ED99ΔsadA, internalisation was decreased approximately threefold compared with that of the parent strain, and treating S. aureus USA300 with TAs increased internalisation by approximately threefold.
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Affiliation(s)
- Arif Luqman
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany.,Biology Department, Institut Teknologi Sepuluh Nopember, Surabaya, Indonesia.,Microbiology Division, Generasi Biologi Indonesia (Genbinesia) Foundation, Gresik, Indonesia
| | - Patrick Ebner
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - Sebastian Reichert
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | - Peter Sass
- Microbial Bioactive Compounds, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
| | | | - Christine Heilmann
- Institute of Medical Microbiology, University Hospital of Münster, Münster, Germany
| | - Peter Ruth
- Institute for Pharmacy, University of Tübingen, Tübingen, Germany
| | - Friedrich Götz
- Microbial Genetics, Interfaculty Institute of Microbiology and Infection Medicine Tübingen (IMIT), University of Tübingen, Tübingen, Germany
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Tsubouchi T, Kunimatsu T, Tsujimoto S, Kiyoshi A, Katsura Y, Oku S, Chihara K, Mine Y, Yamada T, Shimizu I, Bando K. The in vitro pharmacology and non-clinical cardiovascular safety studies of a novel 5-HT 4 receptor agonist, DSP-6952. Eur J Pharmacol 2018; 826:96-105. [PMID: 29501863 DOI: 10.1016/j.ejphar.2018.02.037] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2017] [Revised: 02/08/2018] [Accepted: 02/26/2018] [Indexed: 12/18/2022]
Abstract
The pharmacological activity of DSP-6952, a novel compound was investigated, compared to that of clinically efficacious gastrointestinal (GI) prokinetic 5-hydroxytryptamine4 (5-HT4) receptor agonists. DSP-6952 had a strong affinity of Ki = 51.9 nM for 5-HT4(b) receptor, and produced contraction in the isolated guinea pig colon with EC50 of 271.6 nM and low intrinsic activity of 57%, similar to tegaserod and mosapride. In the development of the 5-HT4 receptor agonists, cardiovascular risk was deliberately evaluated, because some related prokinetics were reported to cause with cardiovascular adverse events, such as ventricular arrhythmias or ischemia. DSP-6952 showed minimal effects up to 100 μM in human ether-a-go-go-related gene (hERG) channels or guinea pig cardiomyocytes. In telemetered conscious monkeys, DSP-6952 did not affect blood pressure or any electrocardiogram (ECG) up to 180 mg/kg, p.o.; however, DSP-6952 transiently increased heart rate, as well as in anesthetized dogs. The positive chronotropic effects of DSP-6952 were completely antagonized by a 5-HT4 receptor antagonist, and another 5-HT4 receptor agonist, TD-5108 also increased heart rate. These effects are considered a class effect seen in clinically developing and marketed 5-HT4 receptor agonists, and have not been regarded as a critical issue in clinical use. DSP-6952 did not induce contraction in the rabbit coronary artery up to 100 μM, which differed from tegaserod or sumatriptan. These results show that DSP-6952 does not have cardiac ischemic risk via coronary vasoconstriction. In conclusion, DSP-6952 is a promising GI prokinetic compound with partial 5-HT4 receptor agonistic activity as well as a favorable cardiovascular safety profile.
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Affiliation(s)
- Tadashi Tsubouchi
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan.
| | - Takeshi Kunimatsu
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Shinji Tsujimoto
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Akihiko Kiyoshi
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Yasunori Katsura
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Seiko Oku
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Kazuhiro Chihara
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Yukiko Mine
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Toru Yamada
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Isao Shimizu
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
| | - Kiyoko Bando
- Drug Research Division, Sumitomo Dainippon Pharma Co., Ltd., 3-1-98 Kasugade-naka, Konohana-ku, Osaka 554-0022, Japan
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6
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Mine Y, Itakura T, Oku S, Asada R, Shimizu I. DSP-6952, a novel 5-HT 4 receptor partial agonist, inhibits visceral hypersensitivity and ameliorates gastrointestinal dysfunction in experimental animals. Eur J Pharmacol 2018; 826:123-132. [DOI: 10.1016/j.ejphar.2018.02.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2017] [Revised: 02/07/2018] [Accepted: 02/07/2018] [Indexed: 01/28/2023]
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Gwynne RM, Clarke AJ, Furness JB, Bornstein JC. Both exogenous 5-HT and endogenous 5-HT, released by fluoxetine, enhance distension evoked propulsion in guinea-pig ileum in vitro. Front Neurosci 2014; 8:301. [PMID: 25285066 PMCID: PMC4168689 DOI: 10.3389/fnins.2014.00301] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Accepted: 09/03/2014] [Indexed: 12/11/2022] Open
Abstract
The roles of 5-HT3 and 5-HT4 receptors in the modulation of intestinal propulsion by luminal application of 5-HT and augmentation of endogenous 5-HT effects were studied in segments of guinea-pig ileum in vitro. Persistent propulsive contractions evoked by saline distension were examined using a modified Trendelenburg method. When 5-HT (30 nM), fluoxetine (selective serotonin reuptake inhibitor; 1 nM), 2-methyl-5-HT (5-HT3 receptor agonist; 1 mM), or RS 67506 (5-HT4 receptor agonist, 1 μM) was infused into the lumen, the pressure needed to initiate persistent propulsive activity fell significantly. A specific 5-HT4 receptor antagonist, SB 207266 (10 nM in lumen), abolished the effects of 5-HT, fluoxetine, and RS 67506, but not those of 2-methyl-5-HT. Granisetron (5-HT3 receptor antagonist; 1 μM in lumen) abolished the effect of 5-HT, fluoxetine, RS 67506, and 2-methyl-5-HT. The NK3 receptor antagonist SR 142801 (100 nM in lumen) blocked the effects of 5-HT, fluoxetine, and 2-methyl-5-HT. SB 207266, granisetron, and SR 142801 had no effect by themselves. Higher concentrations of fluoxetine (100 and 300 nM) and RS 67506 (3 and 10 μM) had no effect on the distension threshold for propulsive contractions. These results indicate that luminal application of exogenous 5-HT, or increased release of endogenous mucosal 5-HT above basal levels, acts to lower the threshold for propulsive contractions in the guinea-pig ileum via activation of 5-HT3 and 5-HT4 receptors and the release of tachykinins. The results further indicate that basal release of 5-HT is insufficient to alter the threshold for propulsive motor activity.
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Affiliation(s)
- Rachel M Gwynne
- Department of Physiology, University of Melbourne Parkville, VIC, Australia
| | - Amanda J Clarke
- Department of Physiology, University of Melbourne Parkville, VIC, Australia
| | - John B Furness
- Departments of Anatomy and Cell Biology, University of Melbourne Parkville, VIC, Australia
| | - Joel C Bornstein
- Department of Physiology, University of Melbourne Parkville, VIC, Australia
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Nirogi R, Kandikere V, Bhyrapuneni G, Saralaya R, Ajjala DR, Aleti RR, Rasheed MA. In-vivo rat striatal 5-HT4 receptor occupancy using non-radiolabelled SB207145. J Pharm Pharmacol 2013; 65:704-12. [DOI: 10.1111/jphp.12030] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2012] [Accepted: 12/19/2012] [Indexed: 12/18/2022]
Abstract
Abstract
Objectives
The objective of the current investigation was to develop a simple, rapid method for determining in-vivo 5-hydroxytryptamine type 4 receptor (5-HT4R) occupancy in rat brain using non-radiolabelled SB207145 as a tracer for accelerating the drug discovery process.
Methods
In-vivo tracer optimization studies for tracer dose, survival intervals and brain distribution profile were carried out in rats. The tracer was pharmacologically validated using potent well-characterized 5-HT4R ligands. The brain regional concentrations of tracer (SB207145); plasma and brain concentrations of 5-HT4R ligands were quantified using high-performance liquid chromatography coupled with a tandem mass spectrometric detector (LC-MS/MS).
Key findings
SB207145 showed a higher specific binding in striatum (1.96 ng/g) and lower binding in cerebellum (0.66 ng/g), which is consistent with findings of other published 5-HT4R expression studies. Pretreatment with potent 5-HT4 ligands dose-dependently reduced striatal SB207145 concentration and the effective dose to achieve 50% receptor occupancy (ED50) values were 4.8, 2.0, 7.4, 9.9, 3.8 and 0.02 mg/kg for GR113808, piboserod, prucalopride, RS67333, TD8954 and PF04995274, respectively.
Conclusions
Results from the mass spectrometry approach to determine 5-HT4R occupancy in rat brain are comparable with those reported using radiolabelled scintillation spectroscopy methods. In conclusion, the LC-MS/MS characterization permits use of tracer at a preclinical stage in high-throughput fashion as well as characterization of target expression.
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Affiliation(s)
- Ramakrishna Nirogi
- Pharmacokinetics and Drug Metabolism, Suven Life Sciences Ltd, Hyderabad, India
- Department of Medicinal Chemistry, Discovery Research, Suven Life Sciences Ltd, Hyderabad, India
| | | | | | - Ramanatha Saralaya
- Pharmacokinetics and Drug Metabolism, Suven Life Sciences Ltd, Hyderabad, India
| | | | | | - Mohammed Abdul Rasheed
- Department of Medicinal Chemistry, Discovery Research, Suven Life Sciences Ltd, Hyderabad, India
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Bassil AK, Taylor CM, Bolton VJN, Gray KM, Brown JD, Cutler L, Summerfield SG, Bruton G, Winchester WJ, Lee K, Sanger GJ. Inhibition of colonic motility and defecation by RS-127445 suggests an involvement of the 5-HT2B receptor in rodent large bowel physiology. Br J Pharmacol 2009; 158:252-8. [PMID: 19371340 DOI: 10.1111/j.1476-5381.2009.00155.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND 5-HT(2B) receptors are localized within the myenteric nervous system, but their functions on motor/sensory neurons are unclear. To explore the role of these receptors, we further characterized the 5-HT(2B) receptor antagonist RS-127445 and studied its effects on peristalsis and defecation. EXPERIMENTAL APPROACH Although reported as a selective 5-HT(2B) receptor antagonist, any interactions of RS-127445 with 5-HT(4) receptors are unknown; this was examined using the recombinant receptor and Biomolecular Interaction Detection technology. Mouse isolated colon was mounted in tissue baths for isometric recording of neuronal contractions evoked by electrical field stimulation (EFS), or under an intraluminal pressure gradient to induce peristalsis; the effects of RS-127445 on EFS-induced and on peristaltic contractions were measured. Faecal output of rats in grid-bottom cages was measured over 3 h following i.p. RS-127445 and separately, validation of the effective doses was achieved by determining the free, unbound fraction of RS-127445 in blood and brain. KEY RESULTS RS-127445 (up to 1 micromol x L(-1)) did not interact with the 5-HT(4) receptor. RS-127445 (0.001-1 micromol x L(-1)) did not affect EFS-induced contractions of the colon, although at 10 micromol x L(-1) the contractions were reduced (to 36 +/- 8% of control, n= 4). RS-127445 (0.1-10 micromol x L(-1)) concentration-dependently reduced peristaltic frequency (n= 4). RS-127445 (1-30 mg x kg(-1)), dose-dependently reduced faecal output, reaching significance at 10 and 30 mg x kg(-1) (n= 6-11). In blood and brain, >98% of RS-127445 was protein-bound. CONCLUSIONS AND IMPLICATIONS High-protein binding of RS-127445 indicates that relatively high doses are required for efficacy. The results suggest that 5-HT(2B) receptors tonically regulate colonic motility.
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Affiliation(s)
- A K Bassil
- Immuno-Inflammation CEDD, GlaxoSmithKline, Stevenage, UK
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10
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Serotonin pharmacology in the gastrointestinal tract: a review. Naunyn Schmiedebergs Arch Pharmacol 2008; 377:181-203. [PMID: 18398601 DOI: 10.1007/s00210-008-0276-9] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2007] [Accepted: 02/15/2008] [Indexed: 12/17/2022]
Abstract
Serotonin (5-hydroxytryptamine or 5-HT) plays a critical physiological role in the regulation of gastrointestinal (GI) function. 5-HT dysfunction may also be involved in the pathophysiology of a number of functional GI disorders, such as chronic constipation, irritable bowel syndrome and functional dyspepsia. This article describes the role of 5-HT in the enteric nervous system (ENS) of the mammalian GI tract and the receptors with which it interacts. Existing serotonergic therapies that have proven effective in the treatment of GI functional disorders and the potential of drugs currently in development are also highlighted. Advances in our understanding of the physiological and pathophysiological roles of 5-HT in the ENS and the identification of selective receptor ligands bodes well for the future development of more efficacious therapies for patients with functional GI disorders.
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Darblade B, Behr-Roussel D, Gorny D, Lebret T, Benoit G, Hieble JP, Brooks D, Alexandre L, Giuliano F. Piboserod (SB 207266), a selective 5-HT4 receptor antagonist, reduces serotonin potentiation of neurally-mediated contractile responses of human detrusor muscle. World J Urol 2005; 23:147-51. [PMID: 15902472 DOI: 10.1007/s00345-005-0499-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2004] [Accepted: 03/24/2005] [Indexed: 12/12/2022] Open
Abstract
The aim of this study is to evaluate the potency of piboserod (SB 207266), a selective 5-HT(4) receptor antagonist, at inhibiting the 5-HT(4)-mediated potentiating effect of serotonin (5-HT) on the neurally-mediated contractile responses of human detrusor strips to electrical field stimulations (EFS). Strips of human detrusor muscle were mounted in Krebs-HEPES buffer under a resting tension of 500 mg and EFS (20 Hz, 1 ms duration at 300 mA for 5 s) was applied continuously at 1 min intervals. After stabilization of the EFS-induced contractions, concentration-response curves to 5-HT (0.1 nM-100 microM) were constructed in the absence or presence of 1 or 100 nM of piboserod. The experiments were performed in the presence of methysergide (1 microM) and ondansetron (3 microM) to block 5HT(1)/5HT(2) and 5-HT(3) receptors, respectively. 5-HT potentiated the contractile responses to EFS of human bladder strips in a concentration-dependent manner, with a maximum mean of 60.0+/-19.9% of the basal EFS-evoked contractions. Piboserod did not modify the basal contractions but concentration-dependently antagonized the ability of 5-HT to enhance bladder strip contractions to EFS. In presence of 1 and 100 nM of piboserod, the maximal 5-HT-induced potentiations were reduced to 45.0+/-7.9 and 38.7+/-8.7%, respectively. A mean apparent antagonist dissociation constant value (K(B)) of 0.56+/-0.09 nM was determined. These data show the ability of piboserod to antagonize with high potency the enhancing properties of 5-HT on neurally-mediated contractions of isolated human bladder strips. Therefore, the 5-HT(4) receptor might represent an attractive pharmacological target for the treatment of overactive bladder.
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Affiliation(s)
- B Darblade
- Pelvipharm, Domaine CNRS, 1 avenue de la terrasse, Bâtiment 5, 91190 Gif-sur-Yvette, France
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12
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Affiliation(s)
- Michel Langlois
- CNRS-BIOCIS (UPRES A 8076), INSERM U-446, Institut de Signalisation et Innovation Thérapeutique (IFR-ISIT), Faculté de Pharmacie, Université de Paris-Sud, 92296 Châtenay-Malabry, France.
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Fedouloff M, Hossner F, Voyle M, Ranson J, Powles J, Riley G, Sanger G. Synthesis and pharmacological activity of metabolites of the 5-HT(4) receptor antagonist SB-207266. Bioorg Med Chem 2001; 9:2119-28. [PMID: 11504648 DOI: 10.1016/s0968-0896(01)00120-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Three metabolites of N-[(1-butyl-4-piperidinyl)methyl]-3,4-dihydro-2H-[1,3]-oxazino[3,2_a]indole-10-carboxamide (SB-207266) (1) were synthesised and their pharmacological activity determined.
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Affiliation(s)
- M Fedouloff
- Department of Synthetic Chemistry, Smithkline Beecham Pharmaceuticals, New Frontiers Science Park, Essex CM19 5AW, Harlow, UK.
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Abstract
Advances in the field of small-bowel motility in the last few years include the delineation of the role of the intrinsic primary afferent neuron in eliciting the peristaltic reflex, the genetic control of the development of the enteric nervous system, and the potential role of the interstitial cells of Cajal as pacemakers of the intestine and colon. New promising molecules have been developed for therapeutic purposes, particularly in the modulators of serotonin receptors. Their effects on sensory and motor function has allowed a better recognition of the important role of 5-hydroxytryptamine in several disorders, especially in irritable bowel syndrome. In this brief review, we have elected to appraise the advances pertaining to human studies, with emphasis on novel methodologies, disease manifestations, and novel therapeutic strategies.
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Affiliation(s)
- Silvia Delgado Aros
- Enteric Neuroscience Group, Gastroenterology Research Unit, Mayo Clinic and Mayo Foundation, Rochester, Minnesota, USA
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15
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Bharucha AE, Camilleri M, Haydock S, Ferber I, Burton D, Cooper S, Tompson D, Fitzpatrick K, Higgins R, Zinsmeister AR. Effects of a serotonin 5-HT(4) receptor antagonist SB-207266 on gastrointestinal motor and sensory function in humans. Gut 2000; 47:667-74. [PMID: 11034583 PMCID: PMC1728108 DOI: 10.1136/gut.47.5.667] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
BACKGROUND Serotonin 5-HT(4) receptors are located on enteric cholinergic neurones and may regulate peristalsis. 5-HT(4) receptors on primary afferent neurones have been postulated to modulate visceral sensation. While 5-HT(4) agonists are used as prokinetic agents, the physiological role of 5-HT(4) receptors in the human gut is unknown. AIMS Our aim was to characterise the role of 5-HT(4) receptors in regulating gastrointestinal motor and sensory function in healthy subjects under baseline and stimulated conditions with a 5-HT(4) receptor antagonist. METHODS Part A compared the effects of placebo to four doses of a 5-HT(4) receptor antagonist (SB-207266) on the cisapride mediated increase in plasma aldosterone (a 5-HT(4) mediated response) and orocaecal transit in 18 subjects. In part B, 52 healthy subjects received placebo, or 0.05, 0.5, or 5 mg of SB-207266 for 10-12 days; gastric, small bowel, and colonic transit were measured by scintigraphy on days 7-9, and fasting and postprandial colonic motor function, compliance, and sensation during distensions were assessed on day 12. RESULTS Part A: 0.5, 5, and 20 mg doses of SB-207266 had significant and quantitatively similar effects, antagonising the cisapride mediated increase in plasma aldosterone and acceleration of orocaecal transit. Part B: SB-207266 tended to delay colonic transit (geometric centre of isotope at 24 (p=0.06) and 48 hours (p=0.08)), but did not have dose related effects on transit, fasting or postprandial colonic motor activity, compliance, or sensation. CONCLUSION 5-HT(4) receptors are involved in the regulation of cisapride stimulated orocaecal transit; SB 207266 tends to modulate colonic transit but not sensory functions or compliance in healthy human subjects.
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Affiliation(s)
- A E Bharucha
- Gastroenterology Research Unit, Mayo Clinic and Mayo Foundation, Rochester, Minnesota 55905, USA.
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Diouf O, Depreux P, Chavatte P, Poupaert JH. Synthesis and preliminary pharmacological results on new naphthalene derivatives as 5-HT(4) receptor ligands. Eur J Med Chem 2000; 35:699-706. [PMID: 10960185 DOI: 10.1016/s0223-5234(00)00163-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The indole derivative GR 113808 is currently used as the reference ligand for labelling the 5-HT(4) serotoninergic receptors. Previous works in our laboratories established the bioisosteric equivalency of the indole heterocycle and naphthalene in a series of melatonin receptor ligands. Based on this knowledge we designed new analogues of GR 113808 by introducing two bioisosteric modifications: firstly, the indole ring was replaced by a naphthalene one and secondly, the ester linkage was replaced by an amide group. Compound 8 emerged within this novel series as it displayed high and selective affinity at 5-HT(4) receptors (Ki 5-HT(4) = 6 nM, Ki 5-HT(3) = 100 nM, Ki values at other 5-HT receptors were higher than 1000 nM). Compound 8 is currently undergoing further pharmacological evaluation.
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Affiliation(s)
- O Diouf
- Institut de chimie pharmaceutique Albert Lespagnol, 3, rue du Professeur Laguesse, BP 83, 59006 cedex, Lille, France
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17
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Sanger GJ, Yoshida M, Yahyah M, Kitazumi K. Increased defecation during stress or after 5-hydroxytryptophan: selective inhibition by the 5-HT(4) receptor antagonist, SB-207266. Br J Pharmacol 2000; 130:706-12. [PMID: 10821802 PMCID: PMC1572116 DOI: 10.1038/sj.bjp.0703367] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/1999] [Revised: 03/13/2000] [Accepted: 03/15/2000] [Indexed: 01/25/2023] Open
Abstract
5-HT(4) receptor antagonism prevents the ability of exogenous 5-HT or 5-HTP to sensitize the intestinal peristaltic reflex and increase the rate of defecation, generally without affecting non-stimulated intestinal function. In this study we confirmed the ability of the selective 5-HT(4) receptor antagonist SB-207266 1 - 1000 microg kg(-1) p.o., to prevent the increase in defecation evoked over a 60 min period by 5-HTP 10 mg kg(-1) s.c. in conscious mice, in the absence of an apparent constipating action. The role of endogenous 5-HT in the mechanisms of increased defecation and/or diarrhoea was then investigated in conscious, fed rats. This was evoked by 180 min exposure to restraint stress, which increased both the number and mean weight of formed, faecal pellets excreted over the entire time period. SB-207266 1 - 1000 microg kg(-1) p.o. (dosed 30 min before restraint) did not affect the increase in defecation evoked during the first 60 min of restraint stress, but significantly and dose-dependently reduced or prevented the increased defecation during the remaining 120 min of the experiment; this action occurred in the absence of an apparent constipating action of SB-207266. In fasted rats exposed to restraint stress, watery diarrhoea developed and although there was a tendency for SB-207266 1 - 1000 microg kg(-1) p.o. (dosed 30 min before restraint) to reduce the incidence of diarrhoea, this inhibition was not complete. We conclude that selective 5-HT(4) receptor antagonism prevents disruptions in defecation behaviours caused by exogenous or endogenous enteric 5-HT and that this activity is not accompanied by a concomitant suppression of activity (constipation-like) within the intestine itself.
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Affiliation(s)
- G J Sanger
- Department of Neuroscience Research, SmithKline Beecham Pharmaceuticals, Third Avenue, Harlow, Essex, CM19 5AW
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18
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Houghton LA, Jackson NA, Whorwell PJ, Cooper SM. 5-HT4 receptor antagonism in irritable bowel syndrome: effect of SB-207266-A on rectal sensitivity and small bowel transit. Aliment Pharmacol Ther 1999; 13:1437-44. [PMID: 10571599 DOI: 10.1046/j.1365-2036.1999.00625.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
BACKGROUND Pre-clinical studies indicate that the 5-hydroxytryptamine (5-HT)4 receptor may be involved in the pathophysiology of irritable bowel syndrome and that antagonism of this receptor may be an effective therapeutic strategy. AIM To investigate the effects of SB-207266-A, a selective 5-HT4 receptor antagonist on rectal sensitivity and small bowel transit in patients with irritable bowel syndrome. METHODS Eighteen patients with diarrhoea-predominant irritable bowel syndrome and a history of increased rectal sensitivity were randomized to receive either SB-207266-A (20 mg) or placebo for 10 days. Following a washout period, patients were then crossed over to receive the alternative therapy for 10 days. Rectal sensitivity and orocaecal transit time were assessed on day 10 of each treatment period. In addition, patients were asked whether they had experienced any changes in their symptoms. RESULTS Fifteen patients completed the study. SB-207266-A significantly increased orocaecal transit time towards normal (placebo: 5.3 h (4.0-7.2 h), mean (IQR) vs. SB-207266-A: 6.5 h (4.8-8.0 h); P=0.027) and tended to decrease rectal sensitivity (volume to discomfort 89 mL (60-150 mL), geometric mean (IQR) vs. 107 mL (75-150 mL); P=0.134). Eleven out of 15 patients reported symptomatic improvements with SB-207266-A but none with placebo. SB-207266-A was well tolerated. CONCLUSION Our results support a role for the 5-HT4 receptor in the pathophysiology of irritable bowel syndrome and suggest that the selective 5-HT4 antagonist, SB-207266-A, is worthy of further evaluation in this disorder.
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Affiliation(s)
- L A Houghton
- Department of Medicine, University Hospital of South Manchester, Manchester, UK
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Smith MI, Banner SE, Sanger GJ. 5-HT4 receptor antagonism potentiates inhibition of intestinal allodynia by 5-HT3 receptor antagonism in conscious rats. Neurosci Lett 1999; 271:61-4. [PMID: 10471214 DOI: 10.1016/s0304-3940(99)00513-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Acute levels of distension were applied by balloon to the colo-rectal region in conscious rats and visceromotor responses observed as abdominal muscle contraction; the threshold was typically between 10-40 mmHg. In saline-pretreated rats, the selective 5-HT3 (granisetron) and 5-HT4 (SB-207266) receptor antagonists had no effects on the visceromotor thresholds. 5-Hydroxytryptophan 10 mg/kg, subcutaneously (s.c.) decreased the distension threshold, indicating mechanical allodynia. This increased sensitivity was dose-dependently inhibited by granisetron but was unaffected by SB-207266 100 microg/kg, s.c., a dose which maximally and selectively antagonizes at 5-HT4 receptors. However, this dose of SB-207266 potentiated the inhibitory activity of submaximally-effective doses of granisetron, reducing the ED50 from 0.83 to 0.02 microg/kg, s.c., but without changing the maximum response or the bell-shaped nature of the dose-response curve for granisetron. These data suggest that 5-HT4 receptor activation enhances the ability of 5-HT3 receptor activation to induce intestinal allodynia.
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Affiliation(s)
- M I Smith
- SmithKline Beecham Pharmaceuticals, Harlow, Essex, UK
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20
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Sanger GJ, Banner SE, Smith MI, Wardle KA. SB-207266: 5-HT4 receptor antagonism in human isolated gut and prevention of 5-HT-evoked sensitization of peristalsis and increased defaecation in animal models. Neurogastroenterol Motil 1998; 10:271-9. [PMID: 9697101 DOI: 10.1046/j.1365-2982.1998.00106.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
SB-207266 is a new 5-HT4 receptor antagonist which in a pilot study reduced the symptoms of irritable bowel syndrome. To help validate this and further studies, we examined the ability of SB-207266 to antagonize at the human 5-HT4 receptor (human isolated intestine) and to affect the mechanisms of peristalsis (guinea-pig isolated ileum) and defaecation (conscious, fed mice). In the human intestine, the potency of 5-HT4 receptor antagonism (pKB 9.98) was similar to that previously demonstrated using a guinea-pig model of the receptor, validating the use of SB-207266 in clinical trials. In each of the animal models, SB-207266 did not affect normal patterns of intestinal motility measured in the absence of exogenous 5-HT. However, SB-207266 10-1000 pM concentration-dependently antagonized the ability of 5-HT (0.1 microM) to sensitize the peristaltic reflex and lower the distension threshold at which peristalsis was evoked. In mice, oral or subcutaneous (s.c.) doses of SB-207266 dose-dependently prevented the ability of the 5-HT precursor, 5-hydroxytryptophan (5-HTP, 10 mg kg-1 s.c.) to increase both the rate of defaecation of formed faecal pellets and their fluid content. SB-207266 was maximally active at 10 micrograms kg-1 s.c. and 1000 micrograms kg-1 p.o. SB-207266 may therefore represent a new class of therapeutic agent, capable of preventing the actions of an important sensitizer of gut function.
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Affiliation(s)
- G J Sanger
- SmithKline Beecham Pharmaceuticals, Neuroscience Research Department, Harlow, Essex, UK
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21
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Schaus JM, Thompson DC, Bloomquist WE, Susemichel AD, Calligaro DO, Cohen ML. Synthesis and structure-activity relationships of potent and orally active 5-HT4 receptor antagonists: indazole and benzimidazolone derivatives. J Med Chem 1998; 41:1943-55. [PMID: 9599243 DOI: 10.1021/jm970857f] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
A series of indole-3-carboxamides, indazole-3-carboxamides, and benzimidazolone-3-carboxamides was synthesized and evaluated for antagonist affinity at the 5-HT4 receptor in the rat esophagus. The endo-3-tropanamine derivatives in the indazole and benzimidazolone series possessed greater 5-HT4 receptor affinity than the corresponding indole analogues. 5-HT4 receptor antagonist affinity was further increased by alkylation at N-1 of the aromatic heterocycle. In a series of 1-isopropylindazole-3-carboxamides, replacement of the bicyclic tropane ring system with the monocyclic piperidine ring system or an acyclic aminoalkylene chain led to potent 5-HT4 receptor antagonists. In particular, those systems in which the basic amine was substituted with groups capable of forming hydrogen bonds showed increased 5-HT4 receptor antagonist activity. While some of these compounds displayed high affinity for other neurotransmitter receptors (in particular, 5-HT3, alpha1, and 5-HT2A receptors), as the conformational flexibility of the amine moiety increased, the selectivity for the 5-HT4 receptor also increased. From this series of compounds, we identified LY353433 (1-(1-methylethyl)-N-[2-[4-[(tricyclo[3.3.1.1(3, 7)]dec-1-ylcarbonyl)amino]-1-piperidinyl]ethyl]-1H-indazole-3- carboxamide) as a potent and selective 5-HT4 receptor antagonist with clinically suitable pharmacodynamics.
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MESH Headings
- Adamantane/administration & dosage
- Adamantane/analogs & derivatives
- Adamantane/chemical synthesis
- Adamantane/chemistry
- Adamantane/pharmacology
- Administration, Oral
- Adrenergic alpha-Antagonists/chemical synthesis
- Adrenergic alpha-Antagonists/chemistry
- Adrenergic alpha-Antagonists/pharmacology
- Animals
- Aorta/drug effects
- Aorta/physiology
- Brain/drug effects
- Brain/metabolism
- Drug Evaluation, Preclinical
- Esophagus/drug effects
- Esophagus/physiology
- Guinea Pigs
- Ileum/drug effects
- Ileum/physiology
- In Vitro Techniques
- Indazoles/administration & dosage
- Indazoles/chemical synthesis
- Indazoles/chemistry
- Indazoles/pharmacology
- Muscle Contraction/drug effects
- Muscle, Smooth/drug effects
- Muscle, Smooth/physiology
- Muscle, Smooth, Vascular/drug effects
- Muscle, Smooth, Vascular/physiology
- Rats
- Receptor, Serotonin, 5-HT2A
- Receptors, Adrenergic, alpha-1/drug effects
- Receptors, Serotonin/drug effects
- Receptors, Serotonin, 5-HT3
- Receptors, Serotonin, 5-HT4
- Serotonin Antagonists/administration & dosage
- Serotonin Antagonists/chemical synthesis
- Serotonin Antagonists/chemistry
- Serotonin Antagonists/pharmacology
- Structure-Activity Relationship
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Affiliation(s)
- J M Schaus
- Lilly Research Laboratories, Eli Lilly and Company, Indianapolis, Indiana 46285, USA
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Cohen ML, Bloomquist W, Calligaro D, Swanson S. Comparative 5-HT4 receptor antagonist activity of LY353433 and its active hydroxylated metabolites. Drug Dev Res 1998. [DOI: 10.1002/(sici)1098-2299(199804)43:4<193::aid-ddr2>3.0.co;2-d] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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23
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Modulators of 5-HT functions in the treatment of Gastrointestinal Disorders. ACTA ACUST UNITED AC 1998. [DOI: 10.1016/s0165-7208(98)80056-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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24
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Eglen RM. 5-Hydroxytryptamine (5-HT)4 receptors and central nervous system function: an update. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 1997; 49:9-24. [PMID: 9388383 DOI: 10.1007/978-3-0348-8863-9_1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- R M Eglen
- Center for Biological Research, Neurobiology Unit, Roche Bioscience, Palo Alto, CA 94304, USA.
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Kennett GA, Bright F, Trail B, Blackburn TP, Sanger GJ. Anxiolytic-like actions of the selective 5-HT4 receptor antagonists SB 204070A and SB 207266A in rats. Neuropharmacology 1997; 36:707-12. [PMID: 9225297 DOI: 10.1016/s0028-3908(97)00037-3] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The highly selective 5-HT4 receptor antagonists, SB 204070A (0.001-0.1 mg/kg s.c., 30 min pretest) and SB 207266A (0.01, 1 and 10 mg/kg p.o., 1 hr pre-test), increased time spent in social interaction without affecting locomotor activity, in a rat 15 min social interaction test under high light, unfamiliar conditions. At 1 and 10 mg/kg s.c., SB 204070A was no longer active. These results are consistent with the profile expected of anxiolytic treatments in this procedure. In a rat 5 min elevated x-maze test, SB 204070A (0.01 and 1 mg/kg s.c., 30 min pre-test) significantly increased the percentage of time spent on the open arms. SB 204070A (0.01 mg/kg s.c.) and SB 207266A (1 mg/kg p.o., 1 hr pre-test) also increased percentage entries to the open arms. Neither compound affected locomotion at any dose tested in the procedure. The effects of both compounds in this procedure are also consistent with anxiolysis. Neither SB 204070A (0.1 or 1 mg/kg s.c., 30 min pre-test) nor SB 207266A (0.1 or 1 mg/kg p.o., 1 hr pre-test) affected either unpunished or punished responding, in a rat Geller-Seifter conflict model of anxiety. The maximal efficacy of both SB 204070A and SB 207266A in the rat social interaction test was similar to that of the benzodiazepine anxiolytic chlordiazepoxide (5 mg/kg s.c. or p.o.) used as a positive control, but was considerably less in the elevated x-maze procedure. The results suggest that 5-HT4 receptor antagonists may have modest anxiolytic-like actions in rats.
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Affiliation(s)
- G A Kennett
- SmithKline Beecham Pharmaceuticals, Harlow, U.K
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