1
|
Grandi D, Solenghi E, Massi M, Morini G. Peripheral infusion of nociceptin/orphanin FQ influences the response of rat gastric and colonic mucosa to repeated stress. REGULATORY PEPTIDES 2010; 160:49-56. [PMID: 19945488 DOI: 10.1016/j.regpep.2009.11.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2009] [Revised: 11/18/2009] [Accepted: 11/22/2009] [Indexed: 10/20/2022]
Abstract
The 17-amino acid peptide nociceptin/orphanin FQ (N/OFQ) plays a role in the regulation of stress responses and of emotional disorders. The objective of this study is to evaluate whether long-term peripheral N/OFQ could dose- and time-dependently influence the responses to repeated cold-restraint stress on the rat gastric and colonic mucosa. Rats were exposed to cold-restraint stress for 3h per day for 1, 2 and 3 consecutive days. N/OFQ was administered at doses of 0.1, 1 and 10 microg/kg/h via Alzet osmotic minipumps. In the gastric fundus, N/OFQ exerted dose-dependent beneficial effects against acute and repeated stress but, after prolonged treatment, became damaging in non-stressed rats. In the distal colon, N/OFQ exerted a protective effect against damage by acute and repeated stress with no influence on epithelial integrity in non-stressed rats. In both regions, the peptide itself dose- and time-dependently reduced intraepithelial mucins. The reduction in mucin content caused by stress was effectively counteracted by N/OFQ, 0.1 microg/kg/h, in the distal colon only. N/OFQ did not modify basal mucosal cell proliferation. The peptide at 0.1 and 1 microg/kg/h had no influence while at 10 microg/kg/h abolished stress-induced increase in cell proliferation. The present results provide evidence that N/OFQ is implicated in the regulation of resting and stress-challenged mucosal integrity and activity of mucin-producing cells.
Collapse
Affiliation(s)
- Daniela Grandi
- Department of Human Anatomy, Pharmacology and Forensic Medicine, University of Parma, Parma, Italy
| | | | | | | |
Collapse
|
2
|
Grandi D, Solenghi E, Guerrini R, Broccardo M, Agostini S, Petrella C, Scaccianoce S, Improta G, Morini G. The hypothalamus-pituitary-adrenal axis does not influence the protective effects of nociceptin/orphanin FQ on the rat gastric mucosa. REGULATORY PEPTIDES 2009; 154:32-8. [PMID: 19046996 DOI: 10.1016/j.regpep.2008.11.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2008] [Revised: 11/03/2008] [Accepted: 11/06/2008] [Indexed: 10/21/2022]
Abstract
The participation of hypothalamus-pituitary-adrenal axis in the gastroprotective effects of nociceptin/orphanin FQ (N/OFQ) has been investigated. Gastric mucosal lesions were induced by intragastric administration of 50% ethanol, 1 ml/rat. Rats received N/OFQ either by the intracerebroventricular (icv) route, at 3 microg/rat, or by the intraperitoneal (ip) route, at 10 microg/kg, 30 min before ethanol administration. The protective effect of icv and ip administered N/OFQ was assessed in adrenalectomized rats and in rats pretreated with the glucocorticoid receptor antagonist, mifepristone, or with the CRF receptor antagonist, alpha-helical CRF(9-41). The damaging effect of ethanol was apparently not influenced by adrenalectomy. N/OFQ markedly reduced macroscopically and histologically assessed gastric mucosal damage. The extent of reduction by N/OFQ was comparable in adrenalectomized and in sham-operated rats, with either icv or ip route of administration. Pretreatment with mifepristone, both icv (80 microg/rat) and ip (10 mg/kg) injected, did not modify the response to icv and ip N/OFQ. Pretreatment with alpha-helical CRF(9-41) (25 microg/rat icv or 250 microg/kg ip), had no effect on the reduction of gastric damage produced by icv or ip N/OFQ. Present findings suggest that the gastroprotective effects of N/OFQ on ethanol-induced damage do not involve the endocrine pathway through the HPA axis.
Collapse
Affiliation(s)
- Daniela Grandi
- Department of Human Anatomy, Pharmacology and Forensic Medicine, University of Parma, Italy
| | | | | | | | | | | | | | | | | |
Collapse
|
3
|
Zádori ZS, Shujaa N, Köles L, Király KP, Tekes K, Gyires K. Nocistatin and nociceptin given centrally induce opioid-mediated gastric mucosal protection. Peptides 2008; 29:2257-65. [PMID: 18930088 DOI: 10.1016/j.peptides.2008.09.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/17/2008] [Revised: 09/16/2008] [Accepted: 09/18/2008] [Indexed: 11/24/2022]
Abstract
Nociceptin (N/OFQ) and nocistatin (NST) are two endogenous neuropeptides derived from the same precursor protein, preproN/OFQ. The aim of the present work was to study the effect of NST on the ethanol-induced mucosal damage compared with that of N/OFQ following intracerebroventricular (i.c.v.) administration in the rat and to analyze the mechanism of the gastroprotective action. It was found that both NST and N/OFQ reduced the mucosal lesions in the same dose range (0.2-1 nmol i.c.v.), but in higher doses (2-5 nmol i.c.v.) the gastroprotective effect of both peptides was highly diminished. The gastroprotective effect of N/OFQ (1 nmol), but not that of NST (1 nmol), was reduced by the selective nociceptin receptor antagonist J-113397 (69 nmol i.c.v.). Similarly, decrease of the gastroprotective effect was observed after the combination of NST (1 nmol) with N/OFQ (0.6 or 1 nmol). However, addition of the gastroprotective effects was observed, when lower dose (0.2 nmol) of NST was given prior to N/OFQ (0.6 nmol). The gastroprotective effect of both N/OFQ and NST was antagonized by naloxone (27 nmol), beta-funaltrexamine (20 nmol), naltrindole (5 nmol) and norbinaltorphimine (14 nmol), the mu-, delta- and kappa-opioid receptor antagonists, respectively, given i.c.v. The mucosal protection was significantly decreased after bilateral cervical vagotomy. The present findings suggest that NST similar to N/OFQ, may also induce gastric mucosal protective action initiated centrally in a vagal-dependent mechanism. Opioid component is likely to be involved in the gastroprotective effect of both NST and N/OFQ.
Collapse
Affiliation(s)
- Zoltán S Zádori
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, Nagyvárad tér 4., 1089 Budapest, Hungary
| | | | | | | | | | | |
Collapse
|
4
|
Broccardo M, Guerrini R, Morini G, Polidori C, Agostini S, Petrella C, Improta G. The gastric effects of UFP-112, a new nociceptin/orphanin receptor agonist, in physiological and pathological conditions. Peptides 2007; 28:1974-81. [PMID: 17765363 DOI: 10.1016/j.peptides.2007.07.021] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2007] [Revised: 07/23/2007] [Accepted: 07/23/2007] [Indexed: 11/26/2022]
Abstract
Nociceptin/orphanin FQ (N/OFQ), the endogenous NOP receptor ligand, centrally modulates gastric motor and secretory functions and prevents ethanol-induced gastric lesions in rats. A recently synthesized N/OFQ analog, [(pF)Phe(4)Aib(7)Arg(14)Lys(15)]N/OFQ-NH(2) (UFP-112), acts as a highly potent and selective peptide agonist for NOP receptors and produces longer-lasting in vitro and in vivo effects in mice than the natural ligand N/OFQ. In this study, we evaluated the effects of centrally (intracerebroventricularly/icv) and peripherally (intraperitoneally/ip) injected UFP-112 on gastric emptying and gastric acid secretion, and on the development of gastric mucosal lesions induced by 50% ethanol in the rat. When injected icv, it dose-dependently delayed gastric emptying of a phenol red meal (by up to 70%), decreased gastric secretion in water-loaded rats after 90 pylorus ligature, and reduced ethanol-induced gastric lesions (by up to 87%). In all three assays, UFP-112 was more effective than N/OFQ. The highly selective NOP receptor antagonist, UFP-101, decreased the efficacy of UFP-112, thus confirming that central NOP receptors mediate inhibitory control on these functional and pathological conditions in rats. Ip injected N/OFQ and UFP-112 induced non-dose-related gastric hypersecretory and antiulcer effects, which UFP-101 partially abolished. Ip N/OFQ appeared equiactive but about 30-100 times less potent than ip UFP-112 in stimulating gastric acid secretion and preventing lesion formation. When ip injected, both UFP-112 and N/OFQ left gastric emptying in rats unchanged, suggesting that peripheral NOP receptors have a role in mediating gastric hypersecretory and antiulcer effects but are not involved in regulating gastric motility. In addition, the inhibitory effects induced by this novel NOP receptor agonist lasted longer than those induced by N/OFQ. In conclusion, UFP-112 is a promising new pharmacological tool for studying the functional roles of the central and peripheral N/OFQ receptor system.
Collapse
Affiliation(s)
- M Broccardo
- Department of Human Physiology and Pharmacology, University of Rome La Sapienza, Italy
| | | | | | | | | | | | | |
Collapse
|
5
|
Grandi D, Solenghi E, Guerrini R, Polidori C, Massi M, Morini G. Nociceptin/orphanin FQ prevents gastric damage induced by cold-restraint stress in the rat by acting in the periphery. Peptides 2007; 28:1572-9. [PMID: 17651865 DOI: 10.1016/j.peptides.2007.06.019] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2007] [Revised: 06/20/2007] [Accepted: 06/20/2007] [Indexed: 02/02/2023]
Abstract
The influence of peripheral nociceptin/orphanin FQ (N/OFQ) on cold restraint-induced gastric mucosal damage in the rat was investigated. Exposure to cold-restraint for 3 and 4h caused the formation of hemorrhagic lesions in the glandular portion of the stomach. N/OFQ dose-dependently decreased lesion formation, in the range 0.03-1 microg/kg/h i.p. Its effect was reversed by the selective NOP receptor antagonist [Nphe(1)Arg(14)Lys(15)]N/OFQ-NH(2) (UFP-101), 30 microg/kg/h ip. The selective NOP receptor agonist [(pF)Phe(4)Aib(7)Arg(14)Lys(15)]N/OFQ-NH(2) (UFP-112), 0.01-0.3 microg/kg/h i.p., similarly reduced lesion formation. Light and scanning electron microscopy confirmed the protective activity of N/OFQ. Cold-restraint stress causes a reduction in mucus content and in adhering mucus layer, partly counteracted by N/OFQ. These results suggest that N/OFQ counteracts acute stress-induced gastric mucosal damage by interacting with NOP receptor and by influencing mucous cell activity.
Collapse
Affiliation(s)
- Daniela Grandi
- Department of Human Anatomy, Pharmacology and Forensic Medicine, University of Parma, Via Volturno 39, I-43100 Parma, Italy
| | | | | | | | | | | |
Collapse
|
6
|
Yu Y, Cui Y, Wang X, Lai LH, Wang CL, Fan YZ, Liu J, Wang R. In vitro characterization of the effects of endomorphin 1 and 2, endogenous ligands for μ-opioid receptors, on mouse colonic motility. Biochem Pharmacol 2007; 73:1384-93. [PMID: 17274956 DOI: 10.1016/j.bcp.2007.01.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2006] [Revised: 01/05/2007] [Accepted: 01/05/2007] [Indexed: 10/23/2022]
Abstract
The effects of endomorphin 1 (EM1) and 2 (EM2) in colonic motility remain unknown. We investigated the effects and mechanisms of these endomorphins (EMs) on the colonic motility in vitro by applying various neural blocking agents and various opioid receptor antagonists. EMs (10(-9) to 10(-6)M) displayed significant stimulatory effects on the basal tonus or spontaneous activity of mouse colon but not of stomach and small intestine. It is noteworthy that the contractile actions of EMs varied slightly among different regions of colonic longitudinal muscle layers, whereas the contractile responses induced by EMs were significantly different among different regions of circular muscle layers. EMs-induced longitudinal or circular muscle contractions were not significantly affected by atropine, N(G)-nitro-l-arginine methyl ester, phentolamine, propranolol and methysergide. Tetrodotoxin, indomethacin and naloxone completely abolished the EMs-induced colonic contractions. Surprisingly, EMs (10(-7)M)-induced longitudinal muscle contractions were significantly attenuated by nor-binaltorphimine (3x10(-6)M). By contrast, pretreatment with naltrindole (10(-6)M) did not significantly affect EMs-induced longitudinal or circular muscle contractions. Interestingly, the circular muscle contractions in response to EM2 (10(-7)M) were not fully blocked by beta-funaltrexamine (6x10(-6)M). Naloxonazine (10(-6)M) almost fully antagonized the EMs-induced longitudinal or circular muscle contractions, and these effects could be only partially reversed by extensive washing. All the results indicated that the mechanisms and sites of actions of EMs were region-specific. Furthermore, these findings showed that the activation of multiple subtypes of opioid receptors, possibly including mu(1) (naloxonazine-sensitive), mu(2) and even other forms of muORs (beta-FNA-insensitive), was required for EMs-induced mouse colonic motility.
Collapse
Affiliation(s)
- Ye Yu
- Institute of Biochemistry and Molecular Biology, State Key Laboratory of Applied Organic Chemistry, Lanzhou University, 222 Tian Shui South Road, Lanzhou 730000, China
| | | | | | | | | | | | | | | |
Collapse
|
7
|
Li HY, Yan X, Xue QL, Zhou YN, Gao Y, Wang R, Liu YM, Ran JT. Effects of nociceptin/orphanin FQ on rats with cathartic colon. World J Gastroenterol 2007; 13:141-5. [PMID: 17206761 PMCID: PMC4065871 DOI: 10.3748/wjg.v13.i1.141] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2006] [Revised: 05/15/2006] [Accepted: 07/10/2006] [Indexed: 02/06/2023] Open
Abstract
AIM To demonstrate the change and effect of nociceptin/orphanin FQ in the colon of rats with cathartic colon. METHODS The cathartic colon model was established by feeding rats rhubarb for 3 mo, the changes of colonic electromyography were investigated by both suspension muscle strips test and serosal recordings of colonic myoelectrical activity. Immunohistochemical staining (S-P methods) and image analysis were used to determine the changes of nociceptin/orphanin FQ in the proximal colon and distal colon of rats with cathartic colon. RESULTS Suspension muscle strips test in vitro showed OFQ (10(-9)-10(-6) mol/L) concentration dependently caused an immediate tonic contraction in the isolated colon. But the increase of tension in cathartic colon was less than control groups (P < 0.01). Intravenous administration of OFQ (1 microg/kg) caused phasic contractions in the proximal colon, while the amplitude of phasic contractions caused by OFQ in cathartic colon was much lower than that in the control groups (2.58 +/- 0.41 vs 4.16 +/- 0.53, t = -2.6, P = 0.012). OFQ was highly expressed in the myenteric plexus of the rat colon but not in the muscle cells. The immunoreactivity of OFQ in the proximal colon in cathartic colon rats decreased significantly compared with the control group (P = 0.001). CONCLUSION Colonic smooth muscle of cathartic colon showed low sensitivity to the stimulation of OFQ, suggesting that it might be caused by the abnormal distribution of OFQ or the abnormalities of receptors, leading to the disorganization of dynamic and incoordinated contractions.
Collapse
Affiliation(s)
- Hai-Yan Li
- Department of Geriatrics, 1st Affiliated Hospital of Lanzhou University, Lanzhou 730000, Gansu Province, China.
| | | | | | | | | | | | | | | |
Collapse
|
8
|
Abstract
Opioids have been used medicinally and recreationally for thousands of years. The clinical use of opioids for gastrointestinal conditions has been limited by central nervous system side effects. A new generation of peripheral opioid receptor ligands free of central nervous system side effects is being developed. Clinical trials with the peripherally acting mu opioid receptor antagonists' alvimopan and N-methylnaltrexone show promise for improving postoperative ileus- and opioid-induced constipation. Likewise, preliminary studies with the peripherally acting kappa opioid agonist fedotozine showed promise in the treatment of irritable bowel syndrome (IBS) and functional dyspepsia. Further studies are on hold presumably due to lack of efficacy in subsequent studies. However, clinical studies are underway for newer kappa opioid agonists such as asimadoline and ADL 10-0101.
Collapse
Affiliation(s)
- Anthony Lembo
- Department of Medicine, Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA.
| |
Collapse
|
9
|
Broccardo M, Scaccianoce S, Del Bianco P, Agostini S, Petrella C, Improta G. Nociceptin/orphanin FQ-induced delay in gastric emptying: role of central corticotropin-releasing factor and glucocorticoid receptors. Neurogastroenterol Motil 2005; 17:871-7. [PMID: 16336503 DOI: 10.1111/j.1365-2982.2005.00717.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
When injected intracerebroventricularly (i.c.v.) in rats, nociceptin/orphanin FQ (N/OFQ) delays gastric emptying and increases plasma corticosterone levels. Our aim in this study was to investigate changes in gastric emptying of a phenol red meal, and the plasma corticosterone response to N/OFQ in adrenalectomized (ADX) rats, in ADX rats injected with corticosterone at 1, 24 and 72 h before the gastric emptying assay, and in intact rats i.c.v. pretreated with a glucocorticoid antagonist (RU486) and with a corticotropin-releasing factor receptor antagonist (alpha-helical CRF9-41). In adrenal intact rats, i.c.v. injection of N/OFQ (2.5 nmol rat-1) significantly delayed gastric emptying (by 70%) and increased plasma corticosterone concentrations. Conversely, in ADX rats, N/OFQ left gastric emptying unchanged. In ADX rats, corticosterone injected at 1, 24 and 72 h before the gastric emptying assay almost restored the N/OFQ-induced delay in gastric emptying. Finally, pretreatment with RU486- and alpha-helical CRF9-41 abolished the N/OFQ-induced inhibition of gastric emptying. These findings suggest that central N/OFQ inhibits gastric emptying through an integrated orphaninergic system-CRF interaction in which corticosterone plays a permissive role.
Collapse
Affiliation(s)
- M Broccardo
- Department of Human Physiology and Pharmacology V. Erspamer, University of Rome La Sapienza, Rome, Italy.
| | | | | | | | | | | |
Collapse
|
10
|
Broccardo M, Linari G, Guerrini R, Agostini S, Petrella C, Improta G. The effects of [Arg14, Lys15] nociceptin/orphanin FQ, a highly potent agonist of the NOP receptor, on in vitro and in vivo gastrointestinal functions. Peptides 2005; 26:1590-7. [PMID: 16112397 DOI: 10.1016/j.peptides.2005.02.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2004] [Revised: 02/18/2005] [Accepted: 02/21/2005] [Indexed: 12/16/2022]
Abstract
Nociceptin/orphanin FQ (N/OFQ) administered into the lateral left cerebral ventricle of rats has been reported to inhibit in vivo gut motor and secretory functions. Recently, a novel N/OFQ analog, [Arg14, Lys15] N/OFQ, was synthesized and demonstrated to behave as a highly potent agonist at the human recombinant N/OFQ peptide (NOP) receptors and to produce long-lasting effects in vivo in mice compared with the natural ligand N/OFQ. In the present study, the pharmacological profile of [Arg14, Lys15] N/OFQ was further evaluated and compared with that of N/OFQ in vitro on guinea pig exocrine pancreas and in vivo on gastric emptying, colonic propulsion and gastric acid secretion in rats. [Arg14, Lys15] N/OFQ and N/OFQ significantly decreased the KCl-evoked amylase secretion from isolated pancreatic lobules of the guinea pig. In in vivo experiments, [Arg14, Lys15] N/OFQ mimicked the effects of N/OFQ, inducing, after intracerebroventricular injection, a delay (up to 70%) in the gastric emptying of a phenol red meal, an increase (about 40 times) of the mean bead colonic expulsion time and a decrease (up to 90%) of gastric acid secretion in water loaded rats after 90 min pylorus ligature. In all these assays, [Arg14, Lys15] N/OFQ was more effective than N/OFQ, and its effective doses were at least 10-fold lower than N/OFQ effective doses. The highly selective NOP receptor antagonist, UFP-101, decreased the efficacy of [Arg14, Lys15] N/OFQ in in vitro and in vivo assays above reported. These findings: (a) show that pancreatic NOP receptors mediate an in vitro inhibitory effect on stimulated guinea pig amylase secretion; (b) confirm that the stimulation of central NOP receptors exerts an inhibitory control on gastric emptying, colonic motility and gastric secretion in rats and (c) put in evidence that [Arg14, Lys15] N/OFQ, being more potent and effective than the natural ligand N/OFQ, represents a new pharmacological tool for the study of the physiological and pharmacological roles mediated by the N/OFQ-NOP receptor system.
Collapse
Affiliation(s)
- M Broccardo
- Department of Human Physiology and Pharmacology, University of Rome La Sapienza, Ple A. Moro 5-00185 Rome, Italy
| | | | | | | | | | | |
Collapse
|
11
|
Polidori C, Massi M, Guerrini R, Grandi D, Lupo D, Morini G. Peripheral mechanisms involved in gastric mucosal protection by intracerebroventricular and intraperitoneal nociceptin in rats. Endocrinology 2005; 146:3861-7. [PMID: 15919744 DOI: 10.1210/en.2005-0397] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Nociceptin (N/OFQ) exerts multiple effects in the gastrointestinal tract after central or peripheral administration. In the present study, we examined the possible peripheral mechanisms mediating gastric protection by N/OFQ in rats. Gastric mucosal lesions were induced by 50% ethanol (1 ml/rat intragastrically). N/OFQ, administered either intracerebroventricularly (3 microg/rat) or ip (10 microg/kg), significantly reduced macroscopic and histological damage. The protective effect of intracerebroventricular N/OFQ was blocked by atropine, subdiaphragmatic vagotomy, and bretylium. The effect of both central and peripheral N/OFQ was blocked by functional ablation of afferent nerves produced by capsaicin, by the antagonist of calcitonin gene-related peptide, CGRP(8-37), and by the nitric oxide synthase inhibitor, N(G)-nitro-L-arginine methyl ester. These results indicate that N/OFQ increases gastric mucosal resistance to ethanol by operating both in the central nervous system and in the periphery. Vagal cholinergic and sympathetic pathways mediate the central activity of N/OFQ, whereas vagal nonmuscarinic pathways mediate the peripheral activity of the peptide. The neuronal circuit involving extrinsic sensory neurons, calcitonin gene-related peptide, and nitric oxide is activated by central as well as peripheral N/OFQ. The study provides evidence that N/OFQ contributes to neurally mediated gastric mucosal protection.
Collapse
Affiliation(s)
- Carlo Polidori
- Department of Experimental Medicine and Public Health, University of Camerino, Italy
| | | | | | | | | | | |
Collapse
|
12
|
Morini G, De Caro G, Guerrini R, Massi M, Polidori C. Nociceptin/orphanin FQ prevents ethanol-induced gastric lesions in the rat. REGULATORY PEPTIDES 2005; 124:203-7. [PMID: 15544860 DOI: 10.1016/j.regpep.2004.07.016] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2004] [Revised: 07/14/2004] [Accepted: 07/15/2004] [Indexed: 11/17/2022]
Abstract
Nociceptin/orphanin FQ (N/OFQ), the endogenous ligand of the NOP receptor, exerts a variety of effects on the gastrointestinal tract. The present study was aimed at evaluating the possible implication of N/OFQ in the maintenance of gastric mucosal integrity. N/OFQ was given either centrally or peripherally 30 min prior to intragastric administration (i.g.) of 1 ml/rat of ethanol (either 25% or 50%, v/v), which produces macroscopically visible gastric lesions. Intracerebroventricular (i.c.v.) injection of 2 microg/rat of N/OFQ significantly reduced lesions caused by 50% ethanol, while 1 microg/rat was enough to significantly reduce lesions caused by 25% ethanol. Intracerebroventricular injection of 5 microg/rat of the selective NOP receptor antagonist, UFP-101, completely reversed the protective effect of N/OFQ, 1 or 4 microg/rat against 25% or 50% ethanol, respectively. The intraperitoneal (i.p.) injection of N/OFQ produced a significant reduction of lesions induced by 50% ethanol, the peak effect being observed at 10 microg/kg. Intraperitoneal pretreatment with UFP-101, 120 microg/kg, completely abolished the protective effect of peripherally injected N/OFQ. Therefore, N/OFQ acts both centrally and peripherally as a protective agent against ethanol-induced gastric lesions, and its effect is mediated by NOP receptors.
Collapse
Affiliation(s)
- Giuseppina Morini
- Department of Human Anatomy, Pharmacology and Forensic Medicine, University of Parma, 43100 Parma, Italy
| | | | | | | | | |
Collapse
|
13
|
N/A. N/A. Shijie Huaren Xiaohua Zazhi 2004; 12:2177-2180. [DOI: 10.11569/wcjd.v12.i9.2177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
|
14
|
Broccardo M, Guerrini R, Petrella C, Improta G. Gastrointestinal effects of intracerebroventricularly injected nociceptin/orphaninFQ in rats. Peptides 2004; 25:1013-20. [PMID: 15203249 DOI: 10.1016/j.peptides.2004.03.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2004] [Revised: 03/26/2004] [Accepted: 03/29/2004] [Indexed: 10/26/2022]
Abstract
Nociceptin/orphanin FQ/(N/OFQ), a novel heptadecapeptide recently isolated from porcine and rat brain, is the endogenous ligand of the N/OFQ peptide receptor (NOP, previously known as ORL-1). In this study we examined the effects of intracerebroventricularly (icv) injected N/OFQ on gastric emptying, gastrointestinal transit, colonic propulsion and gastric acid secretion in rats. N/OFQ (0.01-10 nmol/rat) significantly delayed gastric emptying of a phenol red meal, inhibited transit of a non-absorbable charcoal marker through the small intestine and increased the mean colonic bead expulsion time. These N/OFQ-motor effects were abolished by the NOP receptor selective antagonist [NPhe(1)]N/OFQ(1-13)-NH(2) (50 nmol/rat), but were unaltered by the classical opioid receptor antagonist, naloxone (9.2 micromol/kg). Icv injected N/OFQ (10 nmol/rat) decreased gastric acid secretion in 2-h pylorus ligated rats in a naloxone sensitive manner. [NPhe(1)]N/OFQ(1-13)-NH(2) (100 nmol/rat) icv administered alone stimulated gastric acid secretion. These results indicate that N/OFQ activates via NOP receptor stimulation a central inhibitory pathway modulating gastrointestinal propulsive activity and gastric acid secretion in rats.
Collapse
Affiliation(s)
- Maria Broccardo
- Department of Human Physiology and Pharmacology, University "La Sapienza" Ple A. Moro 5-00185, Rome, Italy
| | | | | | | |
Collapse
|
15
|
Abstract
Opioid treatment for postoperative or chronic pain is frequently associated with adverse effects, the most common being dose-limiting and debilitating bowel dysfunction. Postoperative ileus, although attributable to surgical procedures, is often exacerbated by opioid use during and following surgery. Postoperative ileus is marked by increased inhibitory neural input, heightened inflammatory responses, decreased propulsive movements and increased fluid absorption in the gastrointestinal tract. The use of opioids for chronic pain is characterised by a constellation of symptoms including hard dry stools, straining, incomplete evacuation, bloating, abdominal distension and increased gastroesophageal reflux. The current management of opioid-induced bowel dysfunction among patients receiving opioid analgesics consists primarily of nonspecific ameliorative measures. Intensive investigations into the mode of action of opioids have characterised three opioid receptor classes -mu, delta and kappa- that mediate the myriad of peripheral and central actions of opioids. Activation of mu-opioid receptors in the gastrointestinal tract is responsible for inhibition of gut motility, whereas receptors in the central nervous system mediate the analgesic actions of opioids. Blocking peripheral opioid receptors in the gut is therefore a logical therapeutic target for managing opioid-induced bowel dysfunction. Available opioid antagonists such as naloxone are of limited use because they are readily absorbed, cross the blood-brain barrier, and act at central opioid receptors to reverse analgesia and elicit opioid withdrawal. Methylnaltrexone and alvimopan are recently developed opioid antagonists with activity that is restricted to peripheral receptors. Both have recently shown the ability to reverse opioid-induced bowel dysfunction without reversing analgesia or precipitating central nervous system withdrawal signs in non-surgical patients receiving opioids for chronic pain. In addition, recent clinical studies with alvimopan suggest that it may normalise bowel function without blocking opioid analgesia in abdominal laparotomy patients with opioid-related postoperative ileus.
Collapse
Affiliation(s)
- Andrea Kurz
- Department of Anesthesiology, OUTCOMES RESEARCH Institute, Washington University School of Medicine, St Louis, Missouri, USA
| | | |
Collapse
|
16
|
Ishihara S, Minowa S, Tsuchiya S, Horie S, Watanabe K, Murayama T. Gastric acid secretion stimulated by centrally injected nociceptin in urethane-anesthetized rats. Eur J Pharmacol 2002; 441:105-14. [PMID: 12007927 DOI: 10.1016/s0014-2999(02)01451-6] [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: 10/17/2022]
Abstract
Nociceptin is a preferred endogenous ligand for the orphan opioid receptor-like 1 (ORL1) receptor. Central administration of nociceptin showed various pharmacological effects on analgesia, cardiovascular and renal responses, food intake, and so on. In the present study, we investigated the effect of nociceptin injected into the central nervous system (CNS) on gastric acid secretion in the perfused stomach of urethane-anesthetized rats. Injection of nociceptin (0.55-5.52 nmol per rat) into the fourth cerebroventricle stimulated gastric acid secretion and the secretion was inhibited in atropine-treated (1 mg/kg, i.v.) and vagotomized rats. The secretion induced by nociceptin (1.65 nmol) was not inhibited by the central injection of naloxone (275 nmol, a non-selective antagonist of opioid receptors). The secretion was significantly inhibited by the central injection of [Phe(1)psi(CH(2)-NH)Gly(2)]nociceptin-(1-13)-NH(2) ([F/G]nociceptin-(1-13), 0.21 nmol, an antagonist of ORL1 receptor), although [F/G]nociceptin-(1-13) alone at higher doses (2.10 and 7.31 nmol) markedly stimulated gastric acid secretion. In the 0-40 min period, the secretion induced by nociceptin was inhibited at least partially by CompB (68.8 nmol, a nonpeptidic antagonist of ORL1 receptor). Injection of nociceptin (5.52 nmol) into the lateral cerebroventricle also stimulated the secretion. Injection of nociceptin did not modify gastric acid secretion stimulated by 2-deoxy-D-glucose (200 mg/kg, i.v.). In conclusion, nociceptin injected into the CNS stimulated gastric acid secretion in rats via the ORL1 receptors and through mechanisms involving the vagus nerve.
Collapse
Affiliation(s)
- Satomi Ishihara
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 263-8522, Japan
| | | | | | | | | | | |
Collapse
|
17
|
Abstract
This paper is the twenty-third installment of the annual review of research concerning the opiate system. It summarizes papers published during 2000 that studied the behavioral effects of the opiate peptides and antagonists, excluding the purely analgesic effects, although stress-induced analgesia is included. The specific topics covered this year include stress; tolerance and dependence; learning, memory, and reward; eating and drinking; alcohol and other drugs of abuse; sexual activity, pregnancy, and development; mental illness and mood; seizures and other neurological disorders; electrical-related activity; general activity and locomotion; gastrointestinal, renal, and hepatic function; cardiovascular responses; respiration and thermoregulation; and immunological responses.
Collapse
Affiliation(s)
- A L Vaccarino
- Department of Psychology, University of New Orleans, New Orleans, LA 70148, USA.
| | | |
Collapse
|
18
|
O'Donnell AM, Ellis LM, Riedl MS, Elde RP, Mawe GM. Distribution and chemical coding of orphanin FQ/nociceptin-immunoreactive neurons in the myenteric plexus of guinea pig intestines and sphincter of Oddi. J Comp Neurol 2001; 430:1-11. [PMID: 11135242 DOI: 10.1002/1096-9861(20010129)430:1<1::aid-cne1011>3.0.co;2-h] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Longitudinal muscle-myenteric plexus preparations of guinea pig intestines and sphincter of Oddi (SO) were immunostained for orphanin FQ/nociceptin. Orphanin FQ-immunoreactive (OFQ-IR) neurons and nerve fibers were relatively abundant in the SO, duodenum, ileum, cecum, and distal colon, with fewer neurons and nerve fibers observed in the proximal colon. Double staining with antibodies directed against the neuron-specific RNA binding protein Hu revealed that while the numbers of OFQ-IR neurons per ganglion decreased along the gut tube, similar proportions (7-9%) of neurons in these regions were OFQ-IR, whereas <1% of the neurons in the proximal colon were OFQ positive. In the ileum, where 8% of the myenteric neurons were OFQ-IR, all OFQ-IR neurons expressed choline acetyltransferase. In addition, multiple-label immunohistochemistry demonstrated that 58% of the OFQ-IR neurons were calretinin-IR, 52% were substance P-IR, and 28% were enkephalin-IR. Nitric oxide synthase immunoreactivity was observed in about 5% of OFQ-IR neurons, or 0.4% of the total population, and a similar proportion of the OFQ-IR neurons was positive for vasoactive intestinal peptide. No OFQ-IR neurons were immunoreactive for calbindin, somatostatin, or serotonin. These results, combined with previous studies of chemical coding and projection patterns in the guinea pig myenteric plexus, indicate that OFQ-IR is expressed preferentially in excitatory motor neurons projecting to the longitudinal and circular muscle layers, as well as a small subgroup of descending interneurons. Because OFQ is expressed by excitatory motor neurons, and because this peptide inhibits excitatory neurotransmission in the guinea pig ileum, it is likely that OFQ acts through a feedback autoinhibitory mechanism.
Collapse
Affiliation(s)
- A M O'Donnell
- Department of Anatomy and Neurobiology, The University of Vermont College of Medicine, Burlington, Vermont 05405, USA
| | | | | | | | | |
Collapse
|