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Richardson J, Dezfuli G, Mangel AW, Gillis RA, Vicini S, Sahibzada N. CNS sites controlling the gastric pyloric sphincter: Neuroanatomical and functional study in the rat. J Comp Neurol 2023; 531:1562-1581. [PMID: 37507853 PMCID: PMC10430764 DOI: 10.1002/cne.25530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2022] [Revised: 05/25/2023] [Accepted: 07/09/2023] [Indexed: 07/30/2023]
Abstract
The pyloric sphincter receives parasympathetic vagal innervation from the dorsal motor nucleus of the vagus (DMV). However, little is known about its higher-order neurons and the nuclei that engage the DMV neurons controlling the pylorus. The purpose of the present study was twofold. First, to identify neuroanatomical connections between higher-order neurons and the DMV. This was carried out by using the transneuronal pseudorabies virus PRV-152 injected into rat pylorus torus and examining the brains of these animals for PRV labeling. Second, to identify the specific sites within the DMV that functionally control the motility and tone of the pyloric sphincter. For these studies, experiments were performed to assess the effect of DMV stimulation on pylorus activity in urethane-anesthetized male rats. A strain gauge force transducer was sutured onto the pyloric tonus to monitor tone and motility. L-glutamate (500 pmol/30 nL) was microinjected unilaterally into the rostral and caudal areas of the DMV. Data from the first study indicated that neurons labeled with PRV occurred in the DMV, hindbrain raphe nuclei, midbrain Edinger-Westphal nucleus, ventral tegmental area, lateral habenula, and arcuate nucleus. Data from the second study indicated that microinjected L-glutamate into the rostral DMV results in contraction of the pylorus blocked by intravenously administered atropine and ipsilateral vagotomy. L-glutamate injected into the caudal DMV relaxed the pylorus. This response was abolished by ipsilateral vagotomy but not by intravenously administered atropine or L-NG-nitroarginine methyl ester (L-NAME). These findings identify the anatomical and functional brain neurocircuitry involved in controlling the pyloric sphincter. Our results also show that site-specific stimulation of the DMV can differentially influence the activity of the pyloric sphincter by separate vagal nerve pathways.
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Affiliation(s)
- Janell Richardson
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, D.C., USA
| | - Ghazaul Dezfuli
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, D.C., USA
| | | | - Richard A. Gillis
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, D.C., USA
| | - Stefano Vicini
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, D.C., USA
| | - Niaz Sahibzada
- Department of Pharmacology and Physiology, Georgetown University Medical Center, Washington, D.C., USA
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Horii K, Shiina T, Naitou K, Nakamori H, Horii Y, Shimaoka H, Shimizu Y. Characterization of peristaltic motility in the striated muscle portion of the esophagus using a novel in vivo method in rats. Neurogastroenterol Motil 2019; 31:e13518. [PMID: 30549155 DOI: 10.1111/nmo.13518] [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] [Received: 09/20/2018] [Revised: 10/23/2018] [Accepted: 10/29/2018] [Indexed: 02/08/2023]
Abstract
BACKGROUND Esophageal peristalsis is controlled by the brainstem via vago-vagal reflex. However, the precise regulatory mechanisms in the striated muscle portion are largely unknown. The aim of this study was to characterize peristaltic motility in the portion of the esophagus using a novel in vivo method in rats. METHODS A balloon-tipped catheter was placed in the esophagus of a rat anesthetized with urethane. To induce esophageal peristalsis, the balloon was inflated by water injection. KEY RESULTS When the balloon was inflated near the bronchial bifurcation, the balloon was transported in the aboral direction. Vagotomy abolished the peristaltic response. The threshold volume for inducing esophageal peristalsis varied according to the velocity of balloon distention; the volume being effective to induce peristalsis at a low inflation speed was smaller than the threshold volume at a rapid inflation speed. Even in the absence of inflation, keeping the balloon inside the esophagus during an interval period prevented subsequent induction of peristaltic motility. In addition, a nitric oxide synthase inhibitor abolished the induction of esophageal peristalsis. CONCLUSIONS AND INFERENCES Our findings suggest that (a) in addition to the intensity, the velocity of distention is important for activating the mechanosensory mechanism to induce esophageal peristalsis, (b) tonic inputs from afferent fibers located at the mucosa may reduce the excitability of mechanosensors which is necessary for inducing peristalsis, and (c) nitric oxide plays essential roles in the induction of esophageal peristalsis. These results provide novel insights into the regulatory mechanisms of esophageal motility.
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Affiliation(s)
- Kazuhiro Horii
- Laboratory of Physiology, Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Takahiko Shiina
- Laboratory of Physiology, Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Kiyotada Naitou
- Laboratory of Physiology, Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Hiroyuki Nakamori
- Laboratory of Physiology, Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Yuuki Horii
- Laboratory of Physiology, Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Hiroki Shimaoka
- Laboratory of Physiology, Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan
| | - Yasutake Shimizu
- Laboratory of Physiology, Department of Basic Veterinary Science, The United Graduate School of Veterinary Sciences, Gifu University, Gifu, Japan.,Center for Highly Advanced Integration of Nano and Life Sciences (G-CHAIN), Gifu University, Gifu, Japan
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Browning KN. Excited by fasting? NO. J Physiol 2014; 592:3175-6. [PMID: 25085972 DOI: 10.1113/jphysiol.2014.278663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Kirsteen N Browning
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA, 17033, USA
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Babic T, Bhagat R, Wan S, Browning KN, Snyder M, Fortna SR, Travagli RA. Role of the vagus in the reduced pancreatic exocrine function in copper-deficient rats. Am J Physiol Gastrointest Liver Physiol 2013; 304:G437-48. [PMID: 23275611 PMCID: PMC6842873 DOI: 10.1152/ajpgi.00402.2012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2012] [Accepted: 12/21/2012] [Indexed: 01/31/2023]
Abstract
Copper plays an essential role in the function and development of the central nervous system and exocrine pancreas. Dietary copper limitation is known to result in noninflammatory atrophy of pancreatic acinar tissue. Our recent studies have suggested that vagal motoneurons regulate pancreatic exocrine secretion (PES) by activating selective subpopulations of neurons within vagovagal reflexive neurocircuits. We used a combination of in vivo, in vitro, and immunohistochemistry techniques in a rat model of copper deficiency to investigate the effects of a copper-deficient diet on the neural pathways controlling PES. Duodenal infusions of Ensure or casein, as well as microinjections of sulfated CCK-8, into the dorsal vagal complex resulted in an attenuated stimulation of PES in copper-deficient animals compared with controls. Immunohistochemistry of brain stem slices revealed that copper deficiency reduced the number of tyrosine hydroxylase-immunoreactive, but not neuronal nitric oxide synthase- or choline acetyltransferase-immunoreactive, neurons in the dorsal motor nucleus of the vagus (DMV). Moreover, a copper-deficient diet reduced the number of large (>11 neurons), but not small, intrapancreatic ganglia. Electrophysiological recordings showed that DMV neurons from copper-deficient rats are less responsive to CCK-8 or pancreatic polypeptide than are DMV neurons from control rats. Our results demonstrate that copper deficiency decreases efferent vagal outflow to the exocrine pancreas. These data indicate that the combined selective loss of acinar pancreatic tissue and the decreased excitability of efferent vagal neurons induce a deficit in the vagal modulation of PES.
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Affiliation(s)
- Tanja Babic
- Department of Neural and Behavioral Sciences, Penn State University College of Medicine, Hershey, PA 17033, USA
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NMDA Receptors of Gastric-Projecting Neurons in the Dorsal Motor Nucleus of the Vagus Mediate the Regulation of Gastric Emptying by EA at Weishu (BL21). EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2012; 2012:583479. [PMID: 22654955 PMCID: PMC3359673 DOI: 10.1155/2012/583479] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2012] [Accepted: 02/24/2012] [Indexed: 01/26/2023]
Abstract
A large number of studies have been conducted to explore the efficacy of electroacupuncture (EA) for the treatment of gastrointestinal motility. While several lines of evidence addressed the basic mechanism of EA on gastrointestinal motility regarding effects of limb and abdomen points, the mechanism for effects of the back points on gastric motility still remains unclear. Here we report that the NMDA receptor (NMDAR) antagonist kynurenic acid inhibited the gastric emptying increase induced by high-intensity EA at BL21 and agonist NMDA enhanced the effect of the same treatment. EA at BL21 enhanced NMDAR, but not AMPA receptor (AMPAR) component of miniature excitatory postsynaptic current (mEPSC) in gastric-projecting neurons of the dorsal motor nucleus of the vagus (DMV). In sum, our data demonstrate an important role of NMDAR-mediated synaptic transmission of gastric-projecting DMV neurons in mediating EA at BL21-induced enhancement of gastric emptying.
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Mondal A, Kawamoto Y, Yanaka T, Tsutsui C, Sakata I, Oda SI, Tanaka T, Sakai T. Myenteric neural network activated by motilin in the stomach of Suncus murinus (house musk shrew). Neurogastroenterol Motil 2011; 23:1123-31. [PMID: 22029733 DOI: 10.1111/j.1365-2982.2011.01801.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND It has been shown in human and canine studies that motilin, a gastroprokinetic hormone, induces gastric phase III contractions via the enteric nervous; however, the center of motilin action in the stomach has not been clearly revealed. In the present study, we investigated the neural pathway of motilin-induced gastric contraction by using Suncus murinus, a new animal model for motilin study. METHODS An isolated suncus stomach was used in vitro to determine the mechanism of motilin action through the myenteric plexus. Synthetic suncus motilin (10(-11) -10(-7) molL(-1) ) was added to an organ bath, and the spontaneous contraction response was expressed as a percent of ACh (10(-5) molL(-1) ) responses. Motilin-induced contractions were also studied by a pharmacological method using several receptor antagonists and enzyme inhibitor. KEY RESULTS Suncus motilin induced a concentration-dependent gastric contraction at concentrations from 10(-9) to 10(-7) molL(-1) . The responses to suncus motilin in the stomach were completely abolished by atropine and tetrodotoxin treatment and significantly suppressed by administration of hexamethonium, verapamil, phentolamine, yohimbine, ondansetron, and naloxone, whereas ritanserin, prazosin, timolol, and FK888 did not affect the action of motilin. Additionally, N-nitro l-arginine methylester slightly potentiated the contractions induced by motilin. CONCLUSIONS & INFERENCES The results indicate that motilin directly stimulates and modulates suncus gastric contraction through cholinergic, adrenergic, serotonergic, opioidergic, and NO neurons in the myenteric plexus.
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Affiliation(s)
- A Mondal
- Area of Regulatory Biology, Division of Life Science, Graduate School of Science and Engineering, Saitama University, Sakura-ku, Saitama, Japan
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Seto K, Sasaki T, Katsunuma K, Kobayashi N, Tanaka K, Tack J. Acotiamide hydrochloride (Z-338), a novel prokinetic agent, restores delayed gastric emptying and feeding inhibition induced by restraint stress in rats. Neurogastroenterol Motil 2008; 20:1051-9. [PMID: 18482254 DOI: 10.1111/j.1365-2982.2008.01135.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Acotiamide hydrochloride (Z-338) is a member of new class prokinetic agents currently being developed for the treatment of functional dyspepsia (FD). DNA microarray analysis showed that acotiamide altered the expressions of stress-related genes such as gamma-aminobutyric acid (GABA) receptors, GABA transporters and neuromedin U (NmU) in the medulla oblongata or hypothalamus after administration of acotiamide. Therefore, effects of acotiamide on stress-related symptoms, delayed gastric emptying and feeding inhibition, in rats were examined. Acotiamide significantly improved both delayed gastric emptying and feeding inhibition in restraint stress-induced model, but did not affect both basal gastric emptying and feeding in intact rats, indicating that acotiamide exerted effects only on gastric emptying and feeding impaired by the stress. On the other hand, mosapride showed significant acceleration of gastric emptying in intact and restraint stress-induced model, and itopride showed no effect on restraint stress-induced delayed gastric emptying. In addition, gene expression of NmU increased by restraint stress was suppressed by administration of acotiamide, while acotiamide had no effect on delayed gastric emptying induced by an intracerebroventricular administration of NmU, suggesting that the suppressive effect of acotiamide on gene expression of NmU might be important to restore delayed gastric emptying or feeding inhibition induced by restraint stress. These findings suggest that acotiamide might play an important role in regulation of stress response. As stress is considered to be a major contributing factor in the development of FD, the observed effects may be relevant for symptom improvement in FD.
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Affiliation(s)
- K Seto
- Central Research Laboratories, Zeria Pharmaceutical Co Ltd, Saitama, Japan
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Iwa M, Nakade Y, Pappas TN, Takahashi T. Electroacupuncture improves restraint stress-induced delay of gastric emptying via central glutaminergic pathways in conscious rats. Neurosci Lett 2006; 399:6-10. [PMID: 16406343 DOI: 10.1016/j.neulet.2005.11.069] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2005] [Revised: 11/19/2005] [Accepted: 11/30/2005] [Indexed: 02/07/2023]
Abstract
Acupuncture has been used for treating functional gastrointestinal (GI) disorders. Animal studies demonstrated that acupuncture improves various stress-induced physiological responses. We investigated the effects of electroacupuncture (EA) at ST-36 (Zusanli; lower limb) on stress-induced delay of gastric emptying. Solid food gastric emptying in 90 min was significantly delayed by restraint stress (27.3 +/- 2.1%, n = 8), compared to that of controls (64 +/- 2.1%, n = 8). Restraint stress-induced delay of gastric emptying was significantly restored by the intracisternal (IC)-injection of GABA(A) receptor antagonist, bicuculline methiodide (46.5 +/- 3.1%; n = 6) and GABA(B) receptor antagonist, phaclofen (48 +/- 3.3%; n = 6). Delayed gastric emptying induced by restraint stress was significantly improved by EA at ST-36 (49.7 +/- 1.4%). The stimulatory effect of EA on stress-induced delay of gastric emptying was prevented by pretreatment with IC-injection of glutamate receptor antagonist, kynurenic acid (30.1 +/- 2.1%). In conclusion, restraint stress-induced delay of gastric emptying is mediated via central GABA(A) and GABA(B) receptors. EA at ST-36 stimulates glutaminergic neurons in the brainstem resulting in improvement of stress-induced delay of gastric emptying.
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Affiliation(s)
- Masahiro Iwa
- Department of Surgery, Duke University and Durham Veterans Affairs Medical Center, Surgical Service 112, 508 Fulton Street, NC 27705, USA
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9
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Tsai LH. Function of GABAergic and glutamatergic neurons in the stomach. J Biomed Sci 2005; 12:255-66. [PMID: 15917994 DOI: 10.1007/s11373-005-1357-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2004] [Accepted: 11/18/2004] [Indexed: 11/26/2022] Open
Abstract
Gamma-aminobutyric acid (GABA) and L-glutamic acid (L-Glu) are transmitters of GABAergic and glutamatergic neurons in the enteric interneurons, targeting excitatory or inhibitory GABA receptors or glutamate receptors that modulate gastric motility and mucosal function. GABAergic and glutamatergic neuron immunoreactivity have been found in cholinergic enteric neurons in the stomach. GABA and L-Glu may also subserve hormonal and paracrine signaling. Disruption in gastrointestinal function following perturbation of enteric GABA receptors and glutamate receptors presents potential new target sites for drug development.
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Affiliation(s)
- Li Hsueh Tsai
- Department of Physiology, School of Medicine, Taipei Medical University, Taipei, 11014, Taiwan.
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Affiliation(s)
- TADASHI ISHIGUCHI
- Department of Internal Medicine, Wakayama Medical University Kihoku Hospital, Katsuragicho, Ito‐gun, and
| | - HIDEKAZU ITOH
- Department of Internal Medicine, Wakayama Medical University Kihoku Hospital, Katsuragicho, Ito‐gun, and
| | - MASAO ICHINOSE
- The Second Department of Internal Medicine, Wakayama Medical University, Wakayama city, Wakayama, Japan
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Lewis MW, Hermann GE, Rogers RC, Travagli RA. In vitro and in vivo analysis of the effects of corticotropin releasing factor on rat dorsal vagal complex. J Physiol 2002; 543:135-46. [PMID: 12181286 PMCID: PMC2290483 DOI: 10.1113/jphysiol.2002.019281] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2002] [Accepted: 05/29/2002] [Indexed: 12/16/2022] Open
Abstract
In vivo and in vitro electrophysiological experiments were performed on the rat dorsal vagal complex (DVC, i.e. nucleus of the tractus solitarius, NTS, and dorsal motor nucleus of the vagus, DMV) to examine the effects of corticotropin releasing hormone (CRF) on the central components of the vago-vagal reflex control of gastric function. When applied to gastrointestinal projecting DMV neurones, CRF (10-300 nM) induced a concentration-dependent membrane depolarization, an increase in action potential firing rate and decrease in amplitude of the action potential afterhyperpolarization (P < 0.05). Pretreatment with the non-selective CRF antagonist, astressin (0.5-1 microM) or the selective CRF(2) receptor antagonist, astressin 2B (500 nM) attenuated the CRF-induced increase in firing rate but did not alter basal discharge rate. CRF (30-300 nM) increased the amplitude of excitatory postsynaptic currents (EPSCs) evoked by stimulation of the NTS (P < 0.05). An alteration in the paired pulse ratio indicated the EPSC's increase occurred due to actions at presynaptic sites. In the in vivo anaesthetized rat preparation, bilateral microinjections (20 fmol in 20 nl for each site) of CRF in the DVC decreased gastric motility in rats pretreated with the muscarinic agonist, bethanecol (P < 0.05). The effects of CRF were abolished by systemic administration of the NOS inhibitor, L-NAME, or by bilateral vagotomy. We concluded that CRF had both a direct and an indirect excitatory effect on DMV neurones via activation of CRF(2) receptors and the decrease in gastric motility observed following microinjection of CRF in the DVC is due to the activation of an inhibitory non-adrenergic non-cholinergic input to the gastrointestinal tract.
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Affiliation(s)
- Mark W Lewis
- Department of Gastroenterology, University of Michigan, Ann Arbor, MI 48109, USA
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Tsuchiya S, Horie S, Watanabe K. Stimulatory effects of centrally injected nitric oxide donors on gastric acid secretion in anesthetized rats. JAPANESE JOURNAL OF PHARMACOLOGY 2002; 89:126-32. [PMID: 12120754 DOI: 10.1254/jjp.89.126] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The effects of centrally injected nitric oxide (NO) donors on gastric acid secretion were investigated in continuously perfused stomach of anesthetized rats. The lateral cerebroventricular (LV) injection of NOC5 (30 - 100 microg) and NOC12 (10 - 100 microg) dose-dependently stimulated gastric acid secretion. The LV injection of NOC18 (30 microg) also stimulated gastric acid secretion. The other type of NO donor, sodium nitroprusside (3 - 30 microg, LV), also dose-dependently stimulated gastric acid secretion. The effect of NOC5 at 100 microg was blocked by carboxy-PTIO, an NO scavenger, and by cervical vagotomy. Furthermore, NOC12 (30, 100 microg) dose-dependently stimulated gastric acid secretion in pylorus-ligated conscious rats. These results suggest that centrally injected NO donors stimulate gastric acid secretion in both conscious and anesthetized rats through vagus activation.
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Affiliation(s)
- Shizuko Tsuchiya
- Laboratory of Chemical Pharmacology, Graduate School of Pharmaceutical Sciences, Chiba University, Japan.
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CNS site of action and brainstem circuitry responsible for the intravenous effects of nicotine on gastric tone. J Neurosci 2002. [PMID: 11923442 DOI: 10.1523/jneurosci.22-07-02764.2002] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The purposes of our study were to determine (1) the effects of intravenous (i.v.) nicotine on gastric mechanical function of anesthetized rats, (2) the CNS site of action of nicotine to produce these effects, (3) the CNS nicotinic acetylcholine receptor (nAChR) subtype(s) responsible for mediating the i.v. effects of nicotine, and (4) the brainstem neurocircuitry engaged by i.v. nicotine for eliciting its gastric effects. This was accomplished by monitoring intragastric pressure (gastric tone) and contractility of the fundus and antrum while administering five doses of i.v. nicotine and microinjecting nicotine into specific brainstem nuclei. Additionally, c-Fos expression in the brainstem after i.v. nicotine and pharmacological agents were used as tools to identify the CNS site and circuitry and reveal the nAChR subtype(s) mediating the gastric effects of nicotine. Using these experimental approaches, we found the following. (1) When given intravenously in doses of 56.5, 113, 226, 452, and 904 nmol/kg, nicotine elicited only inhibitory effects on gastric mechanical function. The most sensitive area of the stomach to nicotine was the fundus, and this effect was mediated by the vagus nerve at doses of 56.5, 113, and 226 nmol/kg. (2) The CNS site of action and nAChR subtype responsible were glutamatergic vagal afferent nerve terminals in the medial subnucleus of the tractus solitarious (mNTS) and alpha4beta2, respectively. (3) The brainstem neurocircuitry that was involved appeared to consist of a mNTS noradrenergic pathway projecting to the dorsal motor nucleus of the vagus (DMV). This pathway seems to be activated via nitriergic interneurons engaged by vagally released glutamate in the mNTS and results in alpha2 adrenergic receptor-mediated inhibition of DMV neurons projecting to the fundus and controlling gastric tone.
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Wang J, Liu J, Liu C. Effects of nitric oxide in the dorsal motor nucleus of the vagus on the extrahepatic biliary system in rabbits. Auton Neurosci 2001; 87:46-51. [PMID: 11270140 DOI: 10.1016/s1566-0702(00)00269-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
To investigate whether nitric oxide (NO) in the dorsal motor nucleus of the vagus (DMV) mediated an influence on the extrahepatic biliary system, we studied the effects of microinjection of NO-producing drugs into DMV on the motilities of the gallbladder (GB) and the sphincter of Oddi (SO) in anesthetized rabbits. Microinjection of the NO precursor L-arginine into the rostral DMV produced an increase in the GB and SO motilities, which can be counteracted by both NG-nitro-L-arginine-methyl (L-NAME), an inhibitor of NOS, and reduced hemoglobin (rHb), a scavenger of NO, and were eliminated by bilateral cervical vagotomy. On the other hand, the NO donor sodium nitroprusside (SNP) was able to mimic the excitatory effect of L-arginine. This effect can be antagonized by rHb, but not by L-NAME, for SNP supplied exogenous NO without activating NOS. These results indicate that NO in the DMV mediates an excitatory effect on the extrahepatic biliary system.
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Affiliation(s)
- J Wang
- Department of Physiology, Shandong Medical University, Jinan 250012, Shandong Province, PR China
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Abstract
BACKGROUND & AIMS Nitric oxide (NO) is a major inhibitory neurotransmitter in the gut. This study aimed to identify the effect of chronic deprivation of NO derived from neuronal (nNOS) or endothelial (eNOS) nitric oxide synthase on gastric emptying. METHODS nNOS-deficient (knockout) mice were compared with wild-type mice for gastric size, fluoroscopic appearance after gavage of contrast, and histology of the pyloric sphincter. Wild-type mice treated with the NOS inhibitor N(omega)-nitro L-arginine (L-NA) and eNOS-deficient mice were also compared with wild-type and nNOS-deficient mice for liquid and solid gastric emptying. RESULTS nNOS-deficient mice showed gastric dilation. Fluoroscopy showed delayed gastric emptying of radiologic contrast. There was no marked localized hypertrophy or luminal narrowing at the pyloric sphincter by histology of relaxed wild-type, nNOS-deficient, and eNOS-deficient tissues. Gastric emptying of both solids (28% +/- 27%) and liquids (22% +/- 18%) was significantly delayed in nNOS-deficient mice compared with control wild-type mice (82% +/- 22% for solids; 48% +/- 17% for liquids). eNOS-deficient mice showed no significant difference from wild-type mice (74% +/- 28% for solids; 47% +/- 23% for liquids). Wild-type mice treated acutely with L-NA showed delay in emptying of solids (43% +/- 31%) but not liquids (39% +/- 15%). CONCLUSIONS Chronic depletion of NO from nNOS, but not eNOS, results in delayed gastric emptying of solids and liquids.
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Affiliation(s)
- H Mashimo
- West Roxbury Veterans Affairs Medical Center, West Roxbury, Massachusetts 02132, USA.
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García-Zaragozá E, Barrachina MD, Moreno L, Esplugues JV. Role of central glutamate receptors, nitric oxide and soluble guanylyl cyclase in the inhibition by endotoxin of rat gastric acid secretion. Br J Pharmacol 2000; 130:1283-8. [PMID: 10903967 PMCID: PMC1572196 DOI: 10.1038/sj.bjp.0703436] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
1. This study examines the role of a central pathway involving glutamate receptors, nitric oxide (NO) and cyclic GMP in the acute inhibitory effects of low doses of peripheral endotoxin on pentagastrin-stimulated acid production. 2. Vagotomy or intracisternal (i.c.) microinjections of the NO-inhibitor, N(G)-nitro-L-arginine methyl esther (L-NAME; 200 microg rat(-1)) restored acid secretory responses in endotoxin (10 microg kg(-1), i.v.)-treated rats. 3. The acid-inhibitory effect of i.v. endotoxin (10 microg kg(-1), i.v.) was prevented by prior i.c. administration of the NMDA receptor antagonists, dizocilpine maleate (MK-801; 10 nmol rat(-1)) and D-2-amino-5-phosphono-valeric acid (AP-5; 20 nmol rat(-1)), or the AMPA/kainate antagonist 6,7-dinitroquinoxaline-2,3-dione (DNQX; 10 nmol rat(-1)). However, the competitive metabotropic glutamate receptor antagonist (+)-alpha-methyl-4-carboxyphenylglycine (MCPG; 20 - 1000 nmol rat(-1)) did not antagonize the effects of endotoxin. 4. I.c. administration of L-glutamate (0.1 nmol rat(-1)) inhibited pentagastrin-stimulated gastric acid secretion. Coadministration with L-NAME (200 microg rat(-1)) prevented the inhibition of gastric acid secretion by the aminoacid. 5. I.c. administration of 1H-[1,2, 4]Oxazodiolo[4,3-a]quinoxalin-1-one (ODQ; 100 nmol rat(-1)), a soluble guanylyl cyclase (sGC) blocker, reversed the hyposecretory effect of endotoxin. 6. I.c. administration of the cyclic GMP analogue 8-Bromoguanosine-3,5-cyclic monophosphate (8-Br-cGMP; 100 - 300 nmol rat(-1)) reduced gastric acid production in a dose-dependent manner. 7. We conclude that central NMDA and AMPA/kainate receptors are involved in the acid inhibitory effect of peripherally administered endotoxin. This central pathway involves synthesis of NO, which acts on the enzyme sGC.
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Affiliation(s)
- Eugenia García-Zaragozá
- Department of Pharmacology, Faculty of Medicine, University of Valencia, Avda. Blasco Ibáñez 15, 46010 Valencia, Spain
| | - M Dolores Barrachina
- Department of Pharmacology, Faculty of Medicine, University of Valencia, Avda. Blasco Ibáñez 15, 46010 Valencia, Spain
| | - Lucrecia Moreno
- Department of Pharmacology, Faculty of Medicine, University of Valencia, Avda. Blasco Ibáñez 15, 46010 Valencia, Spain
| | - Juan V Esplugues
- Department of Pharmacology, Faculty of Medicine, University of Valencia, Avda. Blasco Ibáñez 15, 46010 Valencia, Spain
- Author for correspondence:
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17
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Chapter VI Nitric oxide systems in the medulla oblongata and their involvement in autonomic control. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s0924-8196(00)80060-3] [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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18
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Sivarao DV, Krowicki ZK, Hornby PJ. Role of GABAA receptors in rat hindbrain nuclei controlling gastric motor function. Neurogastroenterol Motil 1998; 10:305-13. [PMID: 9697105 DOI: 10.1046/j.1365-2982.1998.00110.x] [Citation(s) in RCA: 88] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
It has been shown in cats that gastric motor control by the dorsal vagal complex and nucleus ambiguus is under a tonic GABAergic influence. Since much more work has been performed in rats to define vago-vagal reflexes controlling gastrointestinal function, an understanding of the potential inhibition by candidate neurotransmitters such as GABA (gamma aminobutyric acid) in the rat dorsal vagal complex (DVC) is essential to assess. Multiple-barrelled micropipettes were used to apply to the dorsal vagal complex the GABAA antagonist, bicuculline methiodide (0.1-1 nmol), and a GABAA agonist, muscimol (10 nmol) prior to micro-injection of the GABAA antagonist. Micro-injections of bicuculline (353 pmol and 1 nmol), which were localized primarily in the dorsal motor nucleus of the vagus, produced significant increases in intragastric pressure and pyloric motility. These responses were abolished by vagotomy and by a prior micro-injection of muscimol. To determine whether GABAergic blockade in the dorsal vagal complex results in gastric motor excitation through excitatory amino acid receptors, kynurenic acid (5 nmol), a kainate/NMDA (N-methyl D-aspartic acid) receptor antagonist, was micro-injected prior to bicuculline. This abolished the increase in gastric motor function normally evoked by bicuculline. In the other two important hindbrain nuclei controlling gastric function, the nucleus raphe obscurus and nucleus ambiguus, bicuculline (353 pmol) significantly increased intragastric pressure via vagally mediated pathways. These data demonstrate that all three rat hindbrain nuclei known to influence gastric function via the vagus nerve are under tonic GABAergic control. In addition, in the dorsal vagal complex, relief from GABAergic inhibition results in increases in gastric motor function through kainate/NMDA receptor-mediated excitation.
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Affiliation(s)
- D V Sivarao
- Department of Pharmacology and Experimental Therapeutics, Louisiana State University Medical Center, New Orleans 70112, USA
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19
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Schleiffer R, Raul F. Nitric oxide and the digestive system in mammals and non-mammalian vertebrates. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART A, PHYSIOLOGY 1997; 118:965-74. [PMID: 9505415 DOI: 10.1016/s0300-9629(97)00026-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The focus of the presentation will review the distribution of nitric oxide (NO)-producing sites in the digestive system in mammals and nonmammalian vertebrates and will center on the roles that NO plays in modulating physiological and pathophysiological functions in digestive system.
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Affiliation(s)
- R Schleiffer
- CJF INSERM 95-09, IRCAD, Hôpitaux Universitaires, Strasbourg, France
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20
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Mizumoto A, Muramatsu S, Yamada T, Itoh Z. Effect of nitric oxide synthase inhibition on plasma motilin release in fasted dogs. REGULATORY PEPTIDES 1997; 71:9-14. [PMID: 9299636 DOI: 10.1016/s0167-0115(97)01004-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Inhibition of nitric oxide (NO) synthase on plasma motilin concentrations is not known. The aim of this study was to examine the effect of NO synthesis inhibitor on gastrointestinal motility and motilin release in conscious dogs. Dogs fitted with force transducers were given N omega-nitro-L-arginine (L-NNA) after the termination of phase III contractions. Blood samples were taken for measurement of motilin concentrations. L-NNA induced phase III-like contractions in the stomach in the duodenum in association with a significant increase in motilin level. Atropine or hexamethonium significantly inhibited L-NNA-induced phase III-like contractions and the increase in motilin level. Atropine or hexamethonium significantly inhibited L-NNA-induced phase III-like contractions and the increase in motilin level. Ondansetron markedly inhibited gastric, but not duodenal, phase III-like contractions without affecting the increase in motilin level caused by L-NNA. Vagotomy affected neither the occurence of phase III-like contractions nor the increase in motilin level produced by L-NNA. We conclude that inhibition of NO synthesis stimulates motilin release via cholinergic pathways independent of the vagus, and induces phase III-like contractions in the stomach and duodenum. Phase III-like contractions induced by L-NNA are mediated through the activation of 5-HT, receptors.
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Affiliation(s)
- A Mizumoto
- Gastrointestinal Research Labs., Gunma University, Maebashi, Japan
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21
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Gustafsson BI, Oland LD, Davison JS. Nitric oxide synthase, oxytocin and vasopressin immunoreactivities in the paraventricular, supraoptic and vagal nuclei of the ferret. JOURNAL OF PHYSIOLOGY, PARIS 1997; 91:215-6. [PMID: 9403797 DOI: 10.1016/s0928-4257(97)89487-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- B I Gustafsson
- Department of Physiology and Biophysics, University of Calgary, Canada
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22
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Krowicki ZK, Sharkey KA, Serron SC, Nathan NA, Hornby PJ. Distribution of nitric oxide synthase in rat dorsal vagal complex and effects of microinjection of nitric oxide compounds upon gastric motor function. J Comp Neurol 1997; 377:49-69. [PMID: 8986872 DOI: 10.1002/(sici)1096-9861(19970106)377:1<49::aid-cne6>3.0.co;2-j] [Citation(s) in RCA: 107] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Nitric oxide (NO) has received attention as a vagal nonadrenergic-noncholinergic (NANC) mediator of gastrointestinal relaxation. The dorsal vagal complex (DVC) is the primary hindbrain site of vagal control of the gastrointestinal tract, and yet the subnuclear distribution of NO and its physiological effects have not been analyzed in this nucleus. Therefore, this study estimates the relative number of NO synthase (NOS)-containing neurons in subnuclear regions of the DVC, identifies NOS-containing vagal abdominal preganglionic neurons in the dorsal motor nucleus of the vagus, and defines a role of NO in the DVC in control of gastric motor function. The location of NADPH-diaphorase-positive staining (a marker of NOS activity) and NOS immunoreactivity overlap in the DVC. In the dorsal motor nucleus of the vagus there are positively stained cells caudal to the obex and at its most rostral extent, but not at the intermediate level. Intraperitoneal fluorogold combined with NADPH-diaphorase activity labels approximately 5% and 15% of fluorogold-immunoreactive cells in the caudal and rostral dorsal motor nucleus of the vagus, respectively. Thus, a portion of NOS-containing neurons are preganglionic vagal neurons projecting to the abdominal viscera. In the nucleus tractus solitarius, the majority of NADPH-diaphorase-positive cells are within the centralis, medial, and ventral/ventrolateral subnuclei. Fiber/terminal staining is present in the subnucleus centralis, subnucleus gelatinosus, subpostremal zone, and the medial nucleus tractus solitarius. The presence of NOS terminal staining implicates NO in afferent control of gastric function in the DVC (e.g., vago-vagal circuits in subnucleus gelatinosus). To determine a role of NO in the DVC, NO-related agents were microinjected into the DVC in alpha-chloralose-anesthetized rats while recording indices of gastric motor function. L-Arginine, microinjected into the DVC, significantly decreases intragastric pressure (-2.2 +/- 0.4 cm2, N = 12), and this effect is abolished by vagotomy. Microinjection of an NOS inhibitor, NG-nitro-L-arginine methyl ester, increases intragastric pressure (1.9 +/- 0.7 cm2, N = 10), with the greatest effect in the DVC rostral to the obex. Overall, it was concluded that tonic release of NO in the DVC mediates gastric relaxation, at least in anesthetized animals, and NOS-containing preganglionic neurons in the dorsal motor nucleus of the vagus may be "command" NANC neurons which control a variety of gastrointestinal functions.
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Affiliation(s)
- Z K Krowicki
- Department of Pharmacology, Louisiana State University Medical Center, New Orleans 70112, USA
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23
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Umehara K, Kataoka K, Ogura T, Esumi H, Kashima K, Ibata Y, Okamura H. Comparative distribution of nitric oxide synthase (NOS) in pancreas of the dog and rat: immunocytochemistry of neuronal type NOS and histochemistry of NADPH-diaphorase. Brain Res Bull 1997; 42:469-78. [PMID: 9128923 DOI: 10.1016/s0361-9230(96)00374-7] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
We investigated the localization of nitric oxide synthase in the pancreas of the dog in comparison to the rat by the methods of immunocytochemistry using antineuronal type nitric oxide synthase serum and histochemistry using NADPH-diaphorase activity. In both species, the most intense staining was observed in neuronal cell bodies and fibers in the pancreas and nitric oxide synthase immunoreactivity was completely colocalized with NADPH-diaphorase activity. However, there were differences of the distribution between the two species. In the dog pancreas, immuno- and NADPH-diaphorase-positive nerve fibers were numerous around pancreatic ducts and moderate around the arteries and the acini but few in the islets. In contrast, in the rat pancreas, immuno- and diaphorase-positive fibers were fewer around the pancreatic ducts and acini and more abundant in the islets. The expression ratio of NADPH-diaphorase in intrapancreatic ganglion cell bodies that were scattered in the interlobular connective tissue was low to moderate (28.1% in the right lobe, 49.5% in the left lobe) in the dog, while the ratio in rat pancreas was very high in both lobes of the pancreas (about 86%). Except for neuronal staining, weak NADPH-diaphorase-positive reactions were detected in the vascular endothelial cells of the pancreas in both species. In rat islet cells, weak neuronal type nitric oxide synthase immunoreactivity was observed; however, in dog islet cells, no immunoreactivity was detected. These results suggest that nitric oxide in the pancreas is derived from vascular endothelium and neuronal tissue in both species and that the neuronal nitrergic regulation of the exocrine and endocrine pancreas is different between the species.
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Affiliation(s)
- K Umehara
- Third Department of Internal Medicine, Kyoto Prefectural University of Medicine, Japan
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Krowicki ZK, Hornby PJ. Contribution of acetylcholine, vasoactive intestinal polypeptide and nitric oxide to CNS-evoked vagal gastric relaxation in the rat. Neurogastroenterol Motil 1996; 8:307-17. [PMID: 8959735 DOI: 10.1111/j.1365-2982.1996.tb00269.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Several in vitro models of gastric relaxation have elucidated a role of nitric oxide (NO) and vasoactive intestinal polypeptide (VIP) in non-adrenergic, non-cholinergic (NANC) vagally mediated gastric relaxation. However, these models do not necessarily mimic the events leading to gastric relaxation in the whole animal. We have recently described a vagally mediated gastric relaxation evoked by micro-injection of substance P (SP) into the nucleus raphe obscurus (NRO). The present study was performed to elucidate whether this CNS-stimulated in vivo gastric relaxation involved acetylcholine, NO and VIP. Atropine (1 mg kg-1 i.v.), reduces both the rapid nadir and sustained gastric relaxation evoked by SP in the NRO, and the residual responses are abolished by NG-Nitro-L-arginine methyl ester hydrochloride (L-NAME, 10 mg kg-1 i.v.), an NO synthase inhibitor. Blockade of NO synthase alone is not sufficient to abolish the effect of SP into the NRO on intragastric pressure. A VIP antagonist, [p-chloro-D-Phe6, Leu17]VIP (32 micrograms i.v.) alone, or with the addition of L-NAME, does not affect the nadir of the gastric relaxation in response to SP microinjected into the NRO; however, both antagonists reduce the CNS-evoked sustained intragastric pressure relaxation. We conclude that, in CNS-evoked gastric relaxation, inhibition of cholinergic pathways is potentially important for both the rapid nadir and sustained gastric relaxation, and both NO and VIP contribute to sustained gastric relaxation.
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Affiliation(s)
- Z K Krowicki
- Department of Pharmacology and Experimental Therapeutics, Louisiana State University Medical Centre, New Orleans 70112, USA
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