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Brouillette RL, Besserer-Offroy É, Mona CE, Chartier M, Lavenus S, Sousbie M, Belleville K, Longpré JM, Marsault É, Grandbois M, Sarret P. Cell-penetrating pepducins targeting the neurotensin receptor type 1 relieve pain. Pharmacol Res 2020; 155:104750. [PMID: 32151680 DOI: 10.1016/j.phrs.2020.104750] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 02/12/2020] [Accepted: 03/05/2020] [Indexed: 01/29/2023]
Abstract
Pepducins are cell-penetrating, membrane-tethered lipopeptides designed to target the intracellular region of a G protein-coupled receptor (GPCR) in order to allosterically modulate the receptor's signaling output. In this proof-of-concept study, we explored the pain-relief potential of a pepducin series derived from the first intracellular loop of neurotensin receptor type 1 (NTS1), a class A GPCR that mediates many of the effects of the neurotensin (NT) tridecapeptide, including hypothermia, hypotension and analgesia. We used BRET-based biosensors to determine the pepducins' ability to engage G protein signaling pathways associated with NTS1 activation. We observed partial Gαq and Gα13 activation at a 10 μM concentration, indicating that these pepducins may act as allosteric agonists of NTS1. Additionally, we used surface plasmon resonance (SPR) as a label-free assay to monitor pepducin-induced responses in CHO-K1 cells stably expressing hNTS1. This whole-cell integrated assay enabled us to subdivide our pepducin series into three profile response groups. In order to determine the pepducins' antinociceptive potential, we then screened the series in an acute pain model (tail-flick test) by measuring tail withdrawal latencies to a thermal nociceptive stimulus, following intrathecal (i.t.) pepducin administration (275 nmol/kg). We further evaluated promising pepducins in a tonic pain model (formalin test), as well as in neuropathic (Chronic Constriction Injury) and inflammatory (Complete Freund's Adjuvant) chronic pain models. We report one pepducin, PP-001, that consistently reduced rat nociceptive behaviors, even in chronic pain paradigms. Finally, we designed a TAMRA-tagged version of PP-001 and found by confocal microscopy that the pepducin reached the rat dorsal root ganglia post i.t. injection, thus potentially modulating the activity of NTS1 at this location to produce its analgesic effect. Altogether, these results suggest that NTS1-derived pepducins may represent a promising strategy in pain-relief.
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Affiliation(s)
- Rebecca L Brouillette
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada.
| | - Élie Besserer-Offroy
- Department of Pharmacology and Therapeutics, McGill University, Montréal, QC, Canada.
| | - Christine E Mona
- Ahmanson Translational Theranostic Division, Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, USA.
| | - Magali Chartier
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada.
| | - Sandrine Lavenus
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada.
| | - Marc Sousbie
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada.
| | - Karine Belleville
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada.
| | - Jean-Michel Longpré
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada.
| | - Éric Marsault
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada.
| | - Michel Grandbois
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada.
| | - Philippe Sarret
- Department of Pharmacology-Physiology, Faculty of Medicine and Health Sciences, Université de Sherbrooke, Sherbrooke, QC, Canada; Institut de pharmacologie de Sherbrooke, Université de Sherbrooke, Sherbrooke, QC, Canada.
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Besserer-Offroy É, Brouillette RL, Lavenus S, Froehlich U, Brumwell A, Murza A, Longpré JM, Marsault É, Grandbois M, Sarret P, Leduc R. The signaling signature of the neurotensin type 1 receptor with endogenous ligands. Eur J Pharmacol 2017; 805:1-13. [DOI: 10.1016/j.ejphar.2017.03.046] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Revised: 03/15/2017] [Accepted: 03/21/2017] [Indexed: 12/17/2022]
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Nakamura K, Okitsu S, Ishida R, Tian S, Igari N, Amano Y. Identification of natural lactoylcholine in lactic acid bacteria-fermented food. Food Chem 2016; 201:185-9. [PMID: 26868564 DOI: 10.1016/j.foodchem.2016.01.055] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 12/05/2015] [Accepted: 01/13/2016] [Indexed: 10/22/2022]
Abstract
Acetylcholine (AcCh) is a major neurotransmitter and an agonist of nicotinic and muscarinic receptors in non-neuronal systems. Artificially synthesized lactoylcholine (LaCh) has potent nicotinic activity equal to that of AcCh. In this study, we report the isolation and purification of natural AcCh and LaCh from a lactic-fermented food known to reduce blood pressure. To our knowledge, we are the first to isolate natural LaCh. The choline esters were isolated using a novel purification procedure combining a weak cation-exchange cartridge with ODS and pentafluorophenyl HPLC columns, and the structure of LaCh was identified via various analyses. Assessment of D- and L-LaCh showed that the isolated LaCh was an enantiomer mixture with a D/L ratio of 1.6. D-LaCh induced vasorelaxation of thoracic aortas from spontaneously hypertensive rats (EC50=3.83×10(-7) M), while L-LaCh did not. Our results suggest that choline esters could be new functional ingredients in lactic-fermented foods.
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Affiliation(s)
- Kozo Nakamura
- Department of Bioscience and Biotechnology, Graduate School of Agriculture, Shinshu University, 8304 Minamiminowa Village, Nagano, Japan; Institute of Agriculture, Academic Assembly, Shinshu University, 8304 Minamiminowa Village, Nagano, Japan.
| | - Sho Okitsu
- Department of Bioscience and Biotechnology, Graduate School of Agriculture, Shinshu University, 8304 Minamiminowa Village, Nagano, Japan.
| | - Ryuya Ishida
- Department of Bioscience and Biotechnology, Graduate School of Agriculture, Shinshu University, 8304 Minamiminowa Village, Nagano, Japan.
| | - Su Tian
- Department of Nutrition and Food Hygiene, School of Public Health, Hebei Medical University, Hebei 050017, China.
| | - Naoki Igari
- Research and Development Department, Daiwa Pharmaceutical Co., Ltd., 1-16-19, Sangenjaya, Setagaya-ku, Tokyo, Japan.
| | - Yoshihiko Amano
- Institute of Engineering, Academic Assembly, Shinshu University, 4-17-1 Wakasato, Nagano City, Nagano, Japan.
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Azriel Y, Liu L, Burcher E, Bucher E. Complex actions of neurotensin in ascending and sigmoid colonic muscle: Involvement of enteric mediators. Eur J Pharmacol 2010; 644:195-202. [PMID: 20615399 DOI: 10.1016/j.ejphar.2010.06.049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2009] [Revised: 06/11/2010] [Accepted: 06/24/2010] [Indexed: 01/07/2023]
Abstract
The brain-gut peptide neurotensin has complex effects on gastrointestinal smooth muscle. Our objective was to elucidate the mechanisms underlying neurotensin contractions in human colon. Discrete concentration response curves to neurotensin were obtained in strips of circular muscle and taenia coli from "normal" ascending and sigmoid colon segments, in the presence and absence of various pharmacological inhibitors. Potency of neurotensin in all regions was similar (pD(2) ~7). Atropine and the selective muscarinic receptor antagonists, methoctramine and darifenacin, had no effect on neurotensin contractions. In ascending colon circular muscle, responses were enhanced by indomethacin (indicating inhibitory prostaglandin mechanisms) and by tetrodotoxin (TTX), hexamethonium and L-NAME, suggesting nicotinic and enteric inhibitory neurotransmission, with involvement of nitric oxide. In sigmoid circular muscle, neurotensin responses were also enhanced by TTX and hexamethonium, but were attenuated in the presence of mepyramine, MEN10627 and CP99994, suggesting inhibitory neuronal mechanisms and involvement of histamine and tachykinins, respectively; L-NAME and the GABA(B) receptor antagonist, CGP36742, were without effect. The transcripts of NTS1 and NTS3 receptors, but not NTS2 receptors, were detected in sigmoid colon circular muscle and taenia coli. No age and gender differences in NTS1 mRNA expression were found. In conclusion, neurotensin contracts circular muscle strips from ascending and sigmoid regions of the human colon via direct (muscle) and indirect (neuronal/non-neuronal mechanisms). The enteric mediators influenced by neurotensin are regionally specific. In taenia coli strips from both ascending and sigmoid colon, neurotensin contractions were unchanged in the presence of inhibitors, suggesting direct actions only.
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Affiliation(s)
- Yael Azriel
- Department of Pharmacology, School of Medical Sciences, University of New South Wales, Sydney, Australia
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Boselli C, Barbone MS, Lucchelli A. Older versus newer antidepressants: Substance P or calcium antagonism? Can J Physiol Pharmacol 2007; 85:1004-11. [DOI: 10.1139/y07-089] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Substance P (SP) is possibly involved in the pathophysiology of depression and anxiety. We investigated interactions between antidepressants on SP-induced effects and their potential calcium-blocking activity in the isolated guinea pig ileum. All the antidepressants tested, except pargyline, moclobemide, mianserin, and reboxetine, were able to inhibit in a concentration-dependent manner the contraction induced by 100 nmol/L SP. Clomipramine, fluoxetine, maprotiline, and amitriptyline (all at 3 μmol/L) flattened the concentration–response curves to SP, resulting in a reduction of up to 59%, 63%, 32%, and 23%, respectively, of the maximum contractile effect. All the antidepressants tested (3 μmol/L), except pargyline, moclobemide, and mianserin, produced a rightward parallel shift of the concentration–response curve to CaCl2. The L-type selective calcium blocker nifedipine and the T-type selective mibefradil showed similar behaviour against both agonists used, SP and CaCl2. The relative order of potency was nifedipine (pA2, 7.6 ± 0.1) > clomipramine (pA2, 7.0 ± 0.1) > fluoxetine (pKB, 6.5 ± 0.1) = mibefradil (pKB, 6.6 ± 0.1) > amitriptyline (pKB, 6.3 ± 0.1) = maprotiline (pKB, 6.2 ± 0.1) > fluvoxamine (pKB, 5.9 ± 0.1). The data reported in the present study suggest that the antidepressants tested did not behave as competitive antagonists versus NK1-receptor subtypes, but their inhibitory action seems to be related to their calcium-blocking properties.
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Affiliation(s)
- C. Boselli
- Department of Experimental and Applied Pharmacology, School of Pharmacy, University of Pavia, Viale Taramelli,14, 27100 Pavia, Italy
| | - M. Santagostino Barbone
- Department of Experimental and Applied Pharmacology, School of Pharmacy, University of Pavia, Viale Taramelli,14, 27100 Pavia, Italy
| | - A. Lucchelli
- Department of Experimental and Applied Pharmacology, School of Pharmacy, University of Pavia, Viale Taramelli,14, 27100 Pavia, Italy
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Zhao D, Pothoulakis C. Effects of NT on gastrointestinal motility and secretion, and role in intestinal inflammation. Peptides 2006; 27:2434-44. [PMID: 16872719 DOI: 10.1016/j.peptides.2005.12.016] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Accepted: 12/01/2005] [Indexed: 01/17/2023]
Abstract
It is well established that interactions of neuropeptides with several cell types at various parts of the intestine are critically involved in intestinal pathophysiology. Among them, neurotensin has been identified as an important mediator in the development and progress of several gastrointestinal functions and disease conditions, exerting its effects by interacting with specific receptors that exert direct and indirect effects on nerves, epithelial cells, and cells of the immune and inflammatory systems. This review summarizes our recent understanding on the participation of neurotensin in the physiology and pathophysiology of the small and large intestine, and discusses various mechanisms that could be involved in these actions.
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Affiliation(s)
- Dezheng Zhao
- Gastrointestinal Neuropeptide Center, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
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Gui X, Degolier TF, Duke GE, Carraway RE. Neurotensin elevates hepatic bile acid secretion in chickens by a mechanism requiring an intact enterohepatic circulation. Comp Biochem Physiol C Toxicol Pharmacol 2000; 127:61-70. [PMID: 11081413 DOI: 10.1016/s0742-8413(00)00126-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Neurotensin (NT), given intravenously at 10-50 pmol/kg per min to anesthetized female chickens equipped with a bile duct fistula, dose-dependently elevated hepatic bile flow and bile acid output but only when the enterohepatic circulation was maintained by returning the bile to the intestinal lumen. Infusion of NT at 10 and 50 pmol/kg per min increased the average hepatic bile acid output over a 30-min period to 138 +/- 11 and 188 +/- 13% of control, respectively. During infusion of NT, plasma levels of immunoreactive NT (iNT) increased in time from the basal level (14 +/- 1.3 pM) to reach steady state at 30 min. There was a near linear relationship between the dose of NT infused and the increment in plasma iNT. In addition, infusion of NT at 40 pmol/kg min gave a plasma level of iNT (approximately/= 88 pM) which was within the range of those observed during duodenal perfusion with lipid (54-300 pM) and near to that measured in hepatic portal blood from fed animals (52 +/- 5 pM). Perfusion of duodenum with lipid released endogenous NT and increased the rate of hepatic bile flow. When NT antagonist SR48692 was given, bile flow rate decreased to the basal level. These results suggest that intestinal NT, released by lipid, may participate in the regulation of hepatic bile acid output by a mechanism requiring an intact enterohepatic circulation.
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Affiliation(s)
- X Gui
- Department of Physiology, University of Massachusetts Medical School, Worcester, MA 01655-0127, USA
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Mitra SP, Carraway RE, Blute R, Luber-Narod J. Agonist induced conformation alteration of neurotensin receptor and the mechanism behind Na+ inhibition of 125I-NT binding. J Recept Signal Transduct Res 1999; 19:995-1021. [PMID: 10533985 DOI: 10.3109/10799899909038436] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
In the absence of Na+, 125I-Neurotensin (125I-NT) binding to the Neurotensin receptor (NTR) produces a stable noncovalent 125I-NT-NTR complex whose dissociation rate is extremely low even after the addition of 1 microM NT, 100 microM SR48692 (antagonist), 100 microM GPPNHP or 100 mM NaCl. Lowering the medium pH to 4.5 enhances the process (approximately 70% in 10 minutes). Labeling by photoactivatable 125I-Tyr3-Azo4-NT identifies a approximately 50 KD Mr band along with several other minor components. Interestingly, the labeling intensity is drastically reduced when binding is performed in the presence of Na+ or GPPNHP. However, a minor reduction is noticed when Na+ or GPPNHP is added to the medium after binding. The binding kinetics indicates that Na+ lowers the rate of 125I-NT association by acting as a noncompetitive inhibitor. On the contrary, Na+ favors the interaction of antagonist, SR48692 by lowering the value of Ki. GTPgamma35S binding to membranes in the presence of 30 mM NaCl suggests that Na+ inhibition of 125I-NT binding is due to the uncoupling of NTR associated G protein(s). In order to explain the entire phenomenon, a two-step, binding model has been proposed. In Step-1, interaction between NT and NTR produces a transient complex, which attains a stable state in the absence of NaCl via step-2, thereby altering the native NTR conformation. The presence of Na+ prevents step-2 by dissociating the transition complex.
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Affiliation(s)
- S P Mitra
- Division of Urology, University of Massachusetts Medical Center, Worcester 01655, USA
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Castagliuolo I, Wang CC, Valenick L, Pasha A, Nikulasson S, Carraway RE, Pothoulakis C. Neurotensin is a proinflammatory neuropeptide in colonic inflammation. J Clin Invest 1999; 103:843-9. [PMID: 10079105 PMCID: PMC408137 DOI: 10.1172/jci4217] [Citation(s) in RCA: 100] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The neuropeptide neurotensin mediates several intestinal functions, including chloride secretion, motility, and cellular growth. However, whether this peptide participates in intestinal inflammation is not known. Toxin A, an enterotoxin from Clostridium difficile, mediates pseudomembranous colitis in humans. In animal models, toxin A causes an acute inflammatory response characterized by activation of sensory neurons and intestinal nerves and immune cells of the lamina propria. Here we show that neurotensin and its receptor are elevated in the rat colonic mucosa following toxin A administration. Pretreatment of rats with the neurotensin receptor antagonist SR-48, 692 inhibits toxin A-induced changes in colonic secretion, mucosal permeability, and histologic damage. Exposure of colonic explants to toxin A or neurotensin causes mast cell degranulation, which is inhibited by SR-48,692. Because substance P was previously shown to mediate mast cell activation, we examined whether substance P is involved in neurotensin-induced mast cell degranulation. Our results show that neurotensin-induced mast cell degranulation in colonic explants is inhibited by the substance P (neurokinin-1) receptor antagonist CP-96,345, indicating that colonic mast activation in response to neurotensin involves release of substance P. We conclude that neurotensin plays a key role in the pathogenesis of C. difficile-induced colonic inflammation and mast cell activation.
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Affiliation(s)
- I Castagliuolo
- Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA.
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DeGolier TF, Place AR, Duke GE, Carraway RE. Neurotensin modulates the composition of pancreatic exocrine secretions in chickens. ACTA ACUST UNITED AC 1999. [DOI: 10.1002/(sici)1097-010x(19990301/01)283:4/5<455::aid-jez15>3.0.co;2-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Abstract
Dispersed cells from chicken brain and liver were found to possess cell surface binding sites for 125I-neurotensin (125I-NT). Scatchard analyses indicated the presence of high affinity (K4, 25-80 pM) and low affinity (Kd, 250-450 pM) components in adult tissues. Binding capacity was reduced 25-40% by incubation with pertussis toxin. Ontogenetic studies indicated that NT receptor capacity increased approximately 20-fold from the embryonic stage to adult. Cross-linking of 125I-NT to intact cells labeled one major band (52 kDa, > or = 90%) and two minor bands (40 and 90 kDa, < or = 10%) which could represent distinct NT-receptors or one receptor partly degraded or cross-linked to G-protein(s). The binding of 125I-NT to dispersed cells was enhanced by reduction with dithoithreitol and suppressed by alkylation with N-ethyl-maleimide (NEM), maleimidocaproic acid (MCA) and p-chloromercuribenzenesulfonate (PCMBS). Since MCA and PCMBS do not permeate cells, this suggests that the sulfhydryl group(s) critical to binding are located within the NT receptor itself. Preincubation of cells with NT prior to treatment with NEM diminished its inhibitory effect, suggesting that the critical SH-group(s) were within the NT binding pocket or were protected by an allosteric effect. These results suggest that one or more of the nine cysteine residues in the NT receptor is involved in the NT binding reaction.
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Affiliation(s)
- S P Mitra
- Department of Physiology, University of Massachusetts Medical Center, Worcester 01655, USA
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Pellissier S, Eribon O, Chabert J, Gully D, Roche M. Peripheral neurotensin participates in the modulation of pre- and postprandial intestinal motility in rats. Neuropeptides 1996; 30:412-9. [PMID: 8923500 DOI: 10.1016/s0143-4179(96)90002-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
The present study was undertaken to determine whether neurotensin is involved in the regulation of the intestinal postprandial motor response and, if so, whether the regulatory pathway depends upon peripheral or central neurotensin secretion. Neurotensin, injected by the i.v. route (5 micrograms/kg) during the fasting state, induced firstly an increased irregular spiking activity during 30-40 min. This effect was followed by an increase of frequency of the myoelectrical complexes during 60 min. When injected by the i.c.v. route, neurotensin (0.5 microgram/kg) reinforced the fasting motility pattern of the small intestine after a latency of 70 min. Neurotensin was ineffective on the colon. The neurotensin receptor antagonist SR 48692 (200 micrograms/kg i.v.) reduced the duration of the postprandial motor response of the small intestine and blocked the late postprandial phase on the proximal colon while it suppressed the early postprandial phase on the distal colon. When administered i.c.v. (20 micrograms/kg), SR 48692 had no effect. It is concluded that neurotensin modulates intestinal postprandial motility essentially by a peripheral regulatory pathway. Endogenous neurotensin is involved in the maintenance of the postprandial motility pattern on the small intestine and the proximal colon while it is involved in the initiation of this response on the distal colon. This suggests that endogenous neurotensin acts via both endocrine and nervous mechanisms.
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Affiliation(s)
- S Pellissier
- Laboratory of Applied Physiology and Pharmacology, University of Savoie, Le Bourget du Lac, France
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