401
|
Price DD, Craggs JG, Zhou Q, Verne GN, Perlstein WM, Robinson ME. Widespread hyperalgesia in irritable bowel syndrome is dynamically maintained by tonic visceral impulse input and placebo/nocebo factors: evidence from human psychophysics, animal models, and neuroimaging. Neuroimage 2009; 47:995-1001. [PMID: 19375508 DOI: 10.1016/j.neuroimage.2009.04.028] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2009] [Revised: 04/02/2009] [Accepted: 04/06/2009] [Indexed: 12/30/2022] Open
Abstract
Irritable bowel syndrome (IBS) is a highly prevalent gastrointestinal disorder that is often accompanied by both visceral and somatic hyperalgesia (enhanced pain from colorectal and somatic stimuli). Neural mechanisms of both types of hyperalgesia have been analyzed by neuroimaging studies of IBS patients and animal analog studies of "IBS-like" rats with delayed rectal and somatic hypersensitivity. Results from these studies suggest that pains associated with both visceral and widespread secondary cutaneous hyperalgesia are dynamically maintained by tonic impulse input from the non-inflamed colon and/or rectum and by brain-to-spinal cord facilitation. Enhanced visceral and somatic pains are accompanied by enhanced pain-related brain activity in IBS patients as compared to normal control subjects; placebos can normalize both their hyperalgesia and enhanced brain activity. That pain in IBS which is likely to be at least partly maintained by peripheral impulse input from the colon/rectum is supported by results showing that local rectal-colonic anesthesia normalizes visceral and somatic hyperalgesia in IBS patients and visceral and somatic hypersensitivity in "IBS-like" rats. Yet these forms of hyperalgesia are also highly modifiable by placebo and nocebo factors (e.g., expectations of relief or distress, respectively). Our working hypothesis is that synergistic interactions occur between placebo/nocebo factors and enhanced afferent processing so as to enhance, maintain, or reduce hyperalgesia in IBS. This explanatory model may be relevant to other persistent pain conditions.
Collapse
Affiliation(s)
- Donald D Price
- Department of Oral Surgery, University of Florida College of Dentistry, Gainesville, Florida, USA.
| | | | | | | | | | | |
Collapse
|
402
|
Choudhury BK, Shi XZ, Sarna SK. Gene plasticity in colonic circular smooth muscle cells underlies motility dysfunction in a model of postinfective IBS. Am J Physiol Gastrointest Liver Physiol 2009; 296:G632-42. [PMID: 19136376 PMCID: PMC2660181 DOI: 10.1152/ajpgi.90673.2008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The cellular mechanisms of motility dysfunction in postinfectious irritable bowel syndrome (PI-IBS) are not known. We used a rat model of neonatal inflammation to test the hypothesis that gene plasticity in colonic circular smooth muscle cells underlies motility dysfunction in PI-IBS. Mild/moderate or severe inflammation was induced in neonatal and adult rats. Experiments were performed in tissues obtained at 7 days (short term) and 6-8 wk (long term) after the induction of inflammation. Severe inflammation in neonatal rats induced persistent long-term smooth muscle hyperreactivity to acetylcholine (ACh), whereas that in adult rat caused smooth muscle hyporeactivity that showed partial recovery in the long term. Mild/moderate inflammation had no effect in neonatal rats, but it induced smooth muscle hyporeactivity to ACh in adult rats, which recovered fully in the long term. Smooth muscle hyperreactivity to ACh resulted in accelerated colonic transit and increase in defecation rate, whereas hyporeactivity had opposite effects. Smooth muscle hyperreactivity to ACh was associated with increase in transcription rate of key cell-signaling proteins of the excitation-contraction coupling alpha1C subunit of Cav1.2 (L-type) calcium channels, Galphaq, and 20-kDa myosin light chain (MLC20), whereas hyporeactivity was associated with their suppression. Inflammation in adult rats induced classical inflammatory response, which was absent in neonatal rats. Severe neonatal inflammation enhanced plasma norepinephrine and muscularis propria vasoactive intestinal polypeptide in the long term. We conclude that severe, but not mild/moderate, inflammation in a state of immature or impaired stress and immune response systems alters the transcription rate of key cell-signaling proteins of excitation-contraction coupling in colonic circular smooth muscle cells to enhance their contractility and accelerate colonic transit and defecation rate.
Collapse
Affiliation(s)
- Barun K. Choudhury
- The University of Texas Medical Branch at Galveston, Enteric Neuromuscular Disorders and Visceral Pain Center, Division of Gastroenterology, Departments of Internal Medicine and Neuroscience and Cell Biology, Galveston, Texas
| | - Xuan-Zheng Shi
- The University of Texas Medical Branch at Galveston, Enteric Neuromuscular Disorders and Visceral Pain Center, Division of Gastroenterology, Departments of Internal Medicine and Neuroscience and Cell Biology, Galveston, Texas
| | - Sushil K. Sarna
- The University of Texas Medical Branch at Galveston, Enteric Neuromuscular Disorders and Visceral Pain Center, Division of Gastroenterology, Departments of Internal Medicine and Neuroscience and Cell Biology, Galveston, Texas
| |
Collapse
|
403
|
Bradesi S, Martinez V, Lao L, Larsson H, Mayer EA. Involvement of vasopressin 3 receptors in chronic psychological stress-induced visceral hyperalgesia in rats. Am J Physiol Gastrointest Liver Physiol 2009; 296:G302-9. [PMID: 19033533 DOI: 10.1152/ajpgi.90557.2008] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Visceral hypersensitivity and stress have been implicated in the pathophysiology of functional gastrointestinal disorders. We used a selective vasopressin 3 (V(3)) receptor antagonist SSR149415 to investigate the involvement of the vasopressin (AVP)/V(3) signaling system in the development of stress-induced visceral hyperalgesia in rats. Rats were exposed to a daily 1-h session of water avoidance stress (WAS) or sham WAS for 10 consecutive days. The visceromotor response to phasic colorectal distension (CRD, 10-60 mmHg) was assessed before and after stress. Animals were treated daily with SSR149415 (0.3, 1, or 3 mg/kg ip 30 min before each WAS or sham WAS session), with a single dose of SSR149415 (1 mg/kg ip), or the selective corticotropin-releasing factor 1 (CRF(1)) antagonist DMP-696 (30 mg/kg po) before CRD at day 11. Effects of a single dose of SSR149415 (10 mg/kg iv) on acute mechanical sensitization during repetitive CRD (12 distensions at 80 mmHg) were also assessed. In vehicle-treated rats, repeated WAS increased the response to CRD, indicating visceral hypersensitivity. Repeated administration of SSR149415 at 1 or 3 mg/kg completely prevented stress-induced visceral hyperalgesia. Similarly, a single dose of DMP-696 or SSR149415 completely blocked hyperalgesic responses during CRD. In contrast, a single dose of SSR149415 did not affect the acute hyperalgesic responses induced by repeated, noxious distension. These data support a major role for V(3) receptors in repeated psychological stress-induced visceral hyperalgesia and suggest that pharmacological manipulation of the AVP/V(3) pathway might represent an attractive alternative to the CRF/CRF(1) pathway for the treatment of chronic stress-related gastrointestinal disorders.
Collapse
Affiliation(s)
- Sylvie Bradesi
- University of California Los Angeles Center for Neurobiology of Stress, Departments of Medicine, Physiology, and Psychiatry, David Geffen School of Medicine at UCLA, Los Angeles, CA 90073.
| | | | | | | | | |
Collapse
|
404
|
Long‐lasting neonatal inflammation enhances pain responses to subsequent inflammation, but not peripheral nerve injury in adult rats. Int J Dev Neurosci 2009; 27:215-22. [PMID: 19429386 DOI: 10.1016/j.ijdevneu.2009.01.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 01/16/2009] [Accepted: 01/18/2009] [Indexed: 11/19/2022] Open
|
405
|
Basic and clinical aspects of gastrointestinal pain. Pain 2009; 141:191-209. [PMID: 19155134 DOI: 10.1016/j.pain.2008.12.011] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2008] [Revised: 09/29/2008] [Accepted: 12/03/2008] [Indexed: 12/12/2022]
Abstract
The gastrointestinal (GI) tract is a system of organs within multicellular animals which facilitates the ingestion, digestion, and absorption of food with subsequent defecation of waste. A complex arrangement of nerves and ancillary cells contributes to the sensorimotor apparatus required to subserve such essential functions that are with the exception of the extreme upper and lower ends of the GI tract normally subconscious. However, it also has the potential to provide conscious awareness of injury. Although this function can be protective, when dysregulated, particularly on a chronic basis, the same system can lead to considerable morbidity. The anatomical and molecular basis of gastrointestinal nociception, conditions associated with chronic unexplained visceral pain, and developments in treatment are presented in this review.
Collapse
|
406
|
Welch MG, Tamir H, Gross KJ, Chen J, Anwar M, Gershon MD. Expression and developmental regulation of oxytocin (OT) and oxytocin receptors (OTR) in the enteric nervous system (ENS) and intestinal epithelium. J Comp Neurol 2009; 512:256-70. [PMID: 19003903 DOI: 10.1002/cne.21872] [Citation(s) in RCA: 94] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Although oxytocin (OT) and oxytocin receptor (OTR) are known for roles in parturition and milk let-down, they are not hypothalamus-restricted. OT is important in nurturing and opposition to stress. Transcripts encoding OT and OTR have been reported in adult human gut, and OT affects intestinal motility. We tested the hypotheses that OT is endogenous to the enteric nervous system (ENS) and that OTR signaling may participate in enteric neurophysiology. Reverse transcriptase polymerase chain reaction confirmed OT and OTR transcripts in adult mouse and rat gut and in precursors of enteric neurons immunoselected from fetal rats. Enteric OT and OTR expression continued through adulthood but was developmentally regulated, peaking at postnatal day 7. Coincidence of the immunoreactivities of OTR and the neural marker Hu was 100% in the P3 and 71% in the adult myenteric plexus, when submucosal neurons were also OTR-immunoreactive. Co-localization with NeuN established that intrinsic primary afferent neurons are OTR-expressing. Because OTR transcripts and protein were detected in the nodose ganglia, OT signaling might also affect extrinsic primary afferent neurons. Although OT immunoreactivity was found only in approximately 1% of myenteric neurons, extensive OT-immunoreactive varicosities surrounded many others. Villus enterocytes were OTR-immunoreactive through postnatal day 17; however, by postnatal day 19, immunoreactivity waned to become restricted to crypts and concentrated at crypt-villus junctions. Immunoelectron microscopy revealed plasmalemmal OTR at enterocyte adherens junctions. We suggest that OT and OTR signaling might be important in ENS development and function and might play roles in visceral sensory perception and neural modulation of epithelial biology.
Collapse
Affiliation(s)
- Martha G Welch
- Department of Psychiatry, Columbia University, New York, New York 10032, USA.
| | | | | | | | | | | |
Collapse
|
407
|
Wang L, Martínez V, Larauche M, Taché Y. Proximal colon distension induces Fos expression in oxytocin-, vasopressin-, CRF- and catecholamines-containing neurons in rat brain. Brain Res 2009; 1247:79-91. [PMID: 18955037 PMCID: PMC3210201 DOI: 10.1016/j.brainres.2008.09.094] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Revised: 09/24/2008] [Accepted: 09/26/2008] [Indexed: 12/11/2022]
Abstract
Little is known about the chemical coding of the brain neuronal circuitry activated by nociceptive signals of visceral origin. We characterized brain nuclei activated during isovolumetric phasic distension of the proximal colon (10 ml, 30 s on/off for 10 min) in conscious male rats, using Fos as a marker of neuronal activation and dual immunohistochemistry to visualize co-localization of Fos expression and oxytocin (OT), arginine-vasopressin (AVP), corticotrophin-releasing factor (CRF) or tyrosine hydroxylase (TH). Proximal colon distension, compared with sham distension, induced a robust increase in Fos-like immunoreactive (IR) neurons in the paraventricular nucleus (PVN), supraoptic nucleus (SON) and accessory neurosecretory nuclei of the hypothalamus, nucleus of the solitary tract (NTS) and ventrolateral medulla (VLM), and to a lower extent, in the locus coeruleus (LC) and Barrington nucleus. Fos-IR neurons in the PVN after colon distension were identified in 81% of OT-IR, 18% AVP-IR and 16% CRF-IR neurons, while in the SON it represented 36% of OT-IR and 16% AVP-IR. Catecholaminergic cell groups in the pons (LC) and medulla (VLM, NTS) were also activated by proximal colon distension. Of the TH-IR neurons in VLM and NTS, 74% and 42% respectively were double labeled. These results indicate that colon distension stimulates OT-, AVP- and CRF-containing hypothalamic neurons, likely involved in the integration of colonic sensory information to modulate autonomic outflow and pain-related responses. Activation of medullary catecholaminergic centers might reflect the afferent and efferent limbs of the functional responses associated to visceral pain.
Collapse
Affiliation(s)
- Lixin Wang
- CURE: Digestive Diseases Research Center and Center for Neurobiological Stress, Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, USA.
| | | | | | | |
Collapse
|
408
|
Wollgarten-Hadamek I, Hohmeister J, Demirakça S, Zohsel K, Flor H, Hermann C. Do burn injuries during infancy affect pain and sensory sensitivity in later childhood? Pain 2009; 141:165-72. [DOI: 10.1016/j.pain.2008.11.008] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2008] [Revised: 11/12/2008] [Accepted: 11/13/2008] [Indexed: 11/28/2022]
|
409
|
Fitzgerald M, Walker SM. Infant pain management: a developmental neurobiological approach. ACTA ACUST UNITED AC 2009; 5:35-50. [DOI: 10.1038/ncpneuro0984] [Citation(s) in RCA: 194] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2008] [Accepted: 10/31/2008] [Indexed: 12/21/2022]
|
410
|
Christianson JA, Bielefeldt K, Altier C, Cenac N, Davis BM, Gebhart GF, High KW, Kollarik M, Randich A, Undem B, Vergnolle N. Development, plasticity and modulation of visceral afferents. ACTA ACUST UNITED AC 2008; 60:171-86. [PMID: 19150371 DOI: 10.1016/j.brainresrev.2008.12.004] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/29/2008] [Indexed: 12/25/2022]
Abstract
Visceral pain is the most common reason for doctor visits in the US. Like somatic pain, virtually all visceral pain sensations begin with the activation of primary sensory neurons innervating the viscera and/or the blood vessels associated with these structures. Visceral afferents also play a central role in tissue homeostasis. Recent studies show that in addition to monitoring the state of the viscera, they perform efferent functions through the release of small molecules (e.g. peptides like CGRP) that can drive inflammation, thereby contributing to the development of visceral pathologies (e.g. diabetes Razavi, R., Chan, Y., Afifiyan, F.N., Liu, X.J., Wan, X., Yantha, J., Tsui, H., Tang, L., Tsai, S., Santamaria, P., Driver, J.P., Serreze, D., Salter, M.W., Dosch, H.M., 2006. TRPV1+ sensory neurons control beta cell stress and islet inflammation in autoimmune diabetes, Cell 127 1123-1135). Visceral afferents are heterogeneous with respect to their anatomy, neurochemistry and function. They are also highly plastic in that their cellular environment continuously influences their response properties. This plasticity makes them susceptible to long-term changes that may contribute significantly to the development of persistent pain states such as those associated with irritable bowel syndrome, pancreatitis, and visceral cancers. This review examines recent insights into visceral afferent anatomy and neurochemistry and how neonatal insults can affect the function of these neurons in the adult. New approaches to the treatment of visceral pain, which focus on primary afferents, will also be discussed.
Collapse
Affiliation(s)
- Julie A Christianson
- University of Pittsburgh School of Medicine, Pittsburgh Center for Pain Research, 200 Lothrop St., Pittsburgh, PA 16261, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
411
|
Zhou EH, Liu HR, Wu HG, Shi Y, Wang XM, Tan LY, Yao LQ, Zhong YS, Jiang Y, Zhang LL. Suspended moxibustion relieves chronic visceral hyperalgesia via serotonin pathway in the colon. Neurosci Lett 2008; 451:144-7. [PMID: 19114087 DOI: 10.1016/j.neulet.2008.12.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2008] [Revised: 12/05/2008] [Accepted: 12/05/2008] [Indexed: 02/06/2023]
Abstract
Experiments in rats have shown that chronic visceral hyperalgesia can be relieved by electro-acupuncture, but the efficacy of suspended moxibustion for relieving chronic visceral hyperalgesia is still unclear. The present study aimed to evaluate the effect of suspended moxibustion on rectal sensory thresholds and to analyze its possible mechanisms when treating chronic visceral hypersensitivity rats. Suspended moxibustion was administered once daily to 37-day-old chronic visceral hypersensitivity rats for 7 days. The two acupoints (ST25, bilateral) were simultaneously given suspended moxibustion. Each treatment lasted for 15 min. Rats in treatment of suspended moxibustion was not anesthetized. Untreated chronic visceral hypersensitivity rats and normal rats were used as controls. The abdominal withdrawal reflex was determined during 30-90 min after the first treatment. A 5-cm long segment of distal colon was harvested after seven treatments and 5-hydroxytryptamine concentrations in the colon were assayed by enzyme-linked immunosorbent assay. Abdominal withdrawal reflex scores from the rectus abdominis in response to colorectal distention were increased in rats with chronic visceral hypersensitivity, and the stimulation at strength of 20 mmHg was significantly depressed by suspended moxibustion. Suspended moxibustion increased the pain threshold and restored normal sensitivity by reducing 5-hydroxytryptamine concentrations in the colon of chronic visceral hypersensitivity rats.
Collapse
Affiliation(s)
- En-Hua Zhou
- Key Laboratory of Acupuncture-Moxibustion and Immunological Effects, Shanghai University of Traditional Chinese Medicine, 650 South WanPing Road, XuHui District, Shanghai 200030, PR China
| | | | | | | | | | | | | | | | | | | |
Collapse
|
412
|
Zhou EH, Liu HR, Wu HG, Shi Y, Wang XM, Yao LQ, Zhong YS, Yang Y. Herb-partition moxibustion relieves chronic visceral hyperalgesia and 5-HT concentration in colon mucosa of rats. Neurol Res 2008; 31:734-7. [PMID: 19108755 DOI: 10.1179/174313209x382313] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The aim of this study was to evaluate the effect of herb-partition moxibustion on rectal sensory thresholds and to analyse possible mechanism of herb-partition moxibustion in treating chronic visceral hypersensitivity rats. METHODS Herb-partition moxibustion was administered to chronic visceral hypersensitivity rats for 7 days (once daily). Two moxa cylinders were used for each point in one treatment. Chronic visceral hypersensitivity rats without herb-partition moxibustion and normal rats were chosen as the control groups. Detection of abdominal withdrawal reflex was performed during 30-90 minutes after the first treatment. After seven treatments, a segment of distal colon (5 cm in length) was harvested, and 5-hydroxytryptamine concentration in the colon tissue was detected by enzyme-linked immunosorbent assay. RESULTS Herb-partition moxibustion significantly depressed abnormally increased AWR scores from the rectus abdominis in response to colorectal distention stimulation at strengths of 40 and 60 mmHg. Herb-partition moxibustion decreased 5-hydroxytryptamine concentration in colon tissue of chronic visceral hypersensitivity rats. CONCLUSION Herb-partition moxibustion enhances the pain threshold of chronic visceral hypersensitivity rats and restores normal sensitivity by 5-hydroxytryptamine concentration decreased in the colon tissue. However, whether herb-partition moxibustion could enhance the pain threshold of IBS patients or not is not concluded in this study because of only small sample rats experiment.
Collapse
Affiliation(s)
- En-Hua Zhou
- Shanghai Institute of Acupuncture-Moxibustion and Meridians, Shanghai University of Traditional Chinese Medicine, 650 South WanPing Road, XuHui District, Shanghai 200030, China
| | | | | | | | | | | | | | | |
Collapse
|
413
|
Kim YS, Lee MY, Choi CS, Sohn YW, Park BR, Choi MG, Nah YH, Choi SC. The effect of chronic variable stress on bowel habit and adrenal function in rats. J Gastroenterol Hepatol 2008; 23:1840-6. [PMID: 18752563 DOI: 10.1111/j.1440-1746.2008.05524.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
BACKGROUND AND AIM Increased colonic motility is a well-known stress response and corticotropin releasing hormone plays an important role in this response, but sequential change of bowel habit and adrenal function during chronic stress has not been reported. The objective of this study was to evaluate the effect of chronic stress on bowel habit and adrenal function. METHODS Male Sprague-Dawley rats were exposed to chronic variable stress (CVS) for 6 weeks. We measured daily the number and weight of pellets and weekly urinary corticosterone. After 6 weeks of experiment, visceromotor response (VMR) to colorectal distention (CRD), serum corticosterone and adrenal glands weight were measured. RESULTS The number and weight of pellets in CVS rats was greater than those of the control rats initially and decreased during the later period. However, CVS rats showed continuously exaggerated daily variation of pellet number than control rats to the end of experimental period. Urinary corticosterone was increased in CVS rat until the fifth week, but urine and serum corticosterone were not statistically different between groups at the sixth week. However, the relative weight of adrenal glands was higher in CVS rats at the sixth week. CVS rats showed exaggerated VMR to CRD than the control rats. CONCLUSIONS The prolonged and variable stress to rats induced sustained bowel habit dysfunction and visceral hypersensitivity without adaptation. Chronic stress also increased adrenal activity from the early phase and finally caused adrenal hypertrophy with relatively decreased activity. But adrenal change was not parallel to bowel habit change and it remains to be seen whether adrenal dysfunction is directly related to bowel habit dysfunction.
Collapse
Affiliation(s)
- Yong S Kim
- Digestive Disease Research Institute and Gastroenterology, School of Medicine, Wonkwang University, Iksan, Korea
| | | | | | | | | | | | | | | |
Collapse
|
414
|
Increased 5-hydroxytryptamine mediates post-inflammatory visceral hypersensitivity via the 5-hydroxytryptamine 3 receptor in rats. Dig Dis Sci 2008; 53:2909-16. [PMID: 18357529 DOI: 10.1007/s10620-008-0244-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2007] [Accepted: 03/05/2008] [Indexed: 01/06/2023]
Abstract
Visceral hypersensitivity often develops after intestinal inflammation, but the pathogenic mechanism has not been clearly elucidated. We investigated whether this post-inflammatory visceral hypersensitivity is mediated by 5-hydroxytryptamine through activation of the 5-hydroxytryptamine 3 receptor. In male Sprague-Dawley rats recovered from acetic acid-induced colitis, we monitored visceral nociceptive response by scoring the abdominal withdrawal reflex and simultaneously measuring the changes in arterial pulse rate. Seven days after induction of colitis, 52% of the rats showed an increased abdominal withdrawal reflex score and arterial pulse rate changes to colorectal distension, indicating that they had post-inflammatory visceral hypersensitivity. The 5-hydroxytryptamine 3 receptor antagonists, alosetron (20 mg/kg, p.o.) and granisetron (10 microg/kg, s.c.), inhibited post-inflammatory visceral hypersensitivity. Administration of a 5-hydroxytryptamine precursor, 5-hydroxytryptophan; 10 mg/kg, s.c.), induced visceral hypersensitivity in naïve rats, which was antagonized by granisetron. Increase in 5-hydroxytryptamine immunoreactive cells in colonic mucosal layer was found both in the rats with post-inflammatory visceral hypersensitivity and in the 5-hydroxytryptophan-treated rats. These results suggest that increased 5-hydroxytryptamine in colonic mucosa mediates post-inflammatory visceral hypersensitivity through activation of the 5-hydroxytryptamine 3 receptor.
Collapse
|
415
|
|
416
|
|
417
|
Vera-Portocarrero LP, Ossipov MH, King T, Porreca F. Reversal of inflammatory and noninflammatory visceral pain by central or peripheral actions of sumatriptan. Gastroenterology 2008; 135:1369-78. [PMID: 18694754 PMCID: PMC4028637 DOI: 10.1053/j.gastro.2008.06.085] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2008] [Revised: 06/23/2008] [Accepted: 06/26/2008] [Indexed: 12/31/2022]
Abstract
BACKGROUND & AIMS Sumatriptan is used specifically to relieve headache pain. The possible efficacy of sumatriptan was investigated in 2 models of visceral pain. METHODS Pancreatic inflammation was induced by intravenous injection of dibutyltin dichloride. Noninflammatory irritable bowel syndrome was induced by intracolonic instillation of sodium butyrate. The effects of systemic sumatriptan on referred hypersensitivity were tested in both models. Effects of sumatriptan within the rostral ventromedial medulla (RVM), a site of descending modulation of visceral pain, was determined by (1) testing the effects of RVM administration of 5HT1(B/D) antagonists on systemic sumatriptan action and (2) determining whether RVM application of sumatriptan reproduced the actions of systemic drug administration. RESULTS Systemic sumatriptan elicited a dose- and time-related blockade of referred hypersensitivity in both models that was blocked by systemic administration of either 5HT1(B) or 5HT1(D) antagonists. Sumatriptan administered into the RVM similarly produced dose- and time-related blockade of referred hypersensitivity in both visceral pain models. This was blocked by local microinjection of the 5HT1(B) antagonist but not the 5HT1(D) antagonist. Microinjection of 5HT1(B) or 5HT1(D) antagonists into the RVM did not block the effects of systemic sumatriptan. CONCLUSIONS Our findings suggest that sumatriptan suppresses either inflammatory or noninflammatory visceral pain, most likely through peripheral 5HT1(B)/(D) receptors. Actions at 5HT1(B) receptors within the RVM offer an additional potential site of action for the modulation of visceral pain by triptans. These studies offer new insights into the development of strategies that may improve therapy of visceral pain conditions using already available medications.
Collapse
|
418
|
Sanchez LC, Elfenbein JR, Robertson SA. Effect of acepromazine, butorphanol, or N-butylscopolammonium bromide on visceral and somatic nociception and duodenal motility in conscious horses. Am J Vet Res 2008; 69:579-85. [PMID: 18447787 DOI: 10.2460/ajvr.69.5.579] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate effects of butorphanol, acepromazine, and N-butylscopolammonium bromide (NBB) on visceral and somatic nociception and duodenal motility in conscious, healthy horses. ANIMALS 6 adult horses. PROCEDURES Visceral nociception was evaluated by use of colorectal distention (CRD) and duodenal distention (DD) threshold. Somatic nociception was evaluated via thermal threshold (TT). Nose-to-ground height, heart rate, and respiratory rate were also measured. Each horse received each treatment in randomized order; investigators were not aware of treatments. Butorphanol was administered IV as a bolus (18 microg/kg) followed by constant rate infusion at 13 microg/kg/h for 2 hours, whereas acepromazine (0.04 mg/kg), NBB (0.3 mg/kg), and saline (0.9% NaCl) solution (2 mL) were administered IV as a bolus followed by constant rate infusion with saline solution (10 mL/h) for 2 hours. Variables were measured before and for 3 hours after treatment. Data were analyzed by use of a 3-factor ANOVA followed by a Bonferroni t test for multiple comparisons. RESULTS Nose-to-ground height decreased after acepromazine. Respiratory rate decreased after acepromazine and increased after butorphanol. Heart rate increased briefly after NBB. Some horses had an increase in TT after butorphanol and acepromazine, but there was not a significant treatment effect over time. Drug effect on DD or motility was not evident. The CRD threshold increased significantly at 5, 65, 155, and 185 minutes after acepromazine and from 5 to 65 minutes after NBB. CONCLUSIONS AND CLINICAL RELEVANCE Each drug caused predictable changes in sedation and vital signs, but consistent anti-nociceptive effects were not evident.
Collapse
Affiliation(s)
- L Chris Sanchez
- Island Whirl Equine Colic Research Laboratory, Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610, USA
| | | | | |
Collapse
|
419
|
Wang J, Gu C, Al-Chaer ED. Altered behavior and digestive outcomes in adult male rats primed with minimal colon pain as neonates. Behav Brain Funct 2008; 4:28. [PMID: 18616817 PMCID: PMC2518152 DOI: 10.1186/1744-9081-4-28] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2008] [Accepted: 07/10/2008] [Indexed: 02/08/2023] Open
Abstract
Background Neonatal colon irritation (CI; pain or inflammation) given for 2 weeks prior to postnatal day 22 (PND22), causes long-lasting functional disorders in rats that can be seen 6 months after the initial insult. This study looked at the effect of varying the frequency and duration of neonatal CI on the rate of growth, digestive outcomes, exploratory activity, and colon and skin sensitivity in adult rats. Methods Male Sprague-Dawley rats were given CI using repeated colorectal distension (CRD) at different time intervals and for varying durations starting at PND 8, 10 or 14. Control rats were handled by the investigator without any intracolonic insertion. Further experiments were done on adult rats. Digestive outcomes (food and water consumption, fecal and urinary outputs) were measured using metabolic cages. Exploratory behavior was measured using digital video tracking in an open field. Cutaneous sensitivity was assessed by measuring the responses to mechanical and heat stimuli applied to the shaved abdomen or hind paws. Visceral sensitivity was measured by recording electromyographic responses, under light isoflurane anesthesia, from the external oblique muscles in response to CRD. Results No significant weight differences were observed between CI and control rats. Exploratory behavior was reduced in rats with neonatal CI compared to control. Digestive outputs and somatic and visceral sensitivity changed between different treatment groups with earlier and more frequent insults yielding a higher deviation from normal. Conclusion The diversity of behavioral and digestive symptoms in these rats parallels the diversity of symptoms in patients with functional gastrointestinal disorders and is consistent with global plastic changes affecting more than one system in the organism.
Collapse
Affiliation(s)
- Jing Wang
- Center for Pain Research, Departments of Pediatrics, Internal Medicine, Neurobiology and Developmental Sciences, University of Arkansas for Medical Sciences, Little Rock, AR, USA.
| | | | | |
Collapse
|
420
|
Yang J, Li Y, Zuo X, Zhen Y, Yu Y, Gao L. Transient receptor potential ankyrin-1 participates in visceral hyperalgesia following experimental colitis. Neurosci Lett 2008; 440:237-41. [PMID: 18583045 DOI: 10.1016/j.neulet.2008.05.093] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2008] [Revised: 05/23/2008] [Accepted: 05/24/2008] [Indexed: 11/15/2022]
Abstract
Transient receptor potential ankyrin-1 (TRPA1) is an important receptor that contributes to inflammatory pain. However, previous studies were mainly concerned with its function in somatic hyperalgesia while few referred to visceral, especially colonic inflammatory hyperalgesia. The present study was aimed to investigate the role of TRPA1 in visceral hyperalgesia after trinitrobenzene sulfonic acid (TNBS)-induced colitis. Results indicate that TNBS induced a significant increase in visceral sensitivity to colonic distension and chemical irritation accompanied by up-regulation of TRPA1 in colonic afferent dorsal root ganglia (DRG). Intrathecal administration of TRPA1 antisense (AS) oligodeoxynucleotide (ODN) reduced the TRPA1 expression in DRG as well as suppressed the colitis-induced hyperalgesia to nociceptive colonic distension and intracolonic allyl isothiocyanate (AITC). Meanwhile the TRPA1 antisense ODN had no effect on transient receptor potential vanilloid-1 (TRPV1) expression, which was proposed to highly co-express with TRPA1, and no effect on the response to TRPV1 agonist, capsaicin. These data suggest an apparent role of TRPA1 in visceral hyperalgesia following colitis that might provide a novel therapeutic target for the relief of pain.
Collapse
Affiliation(s)
- Jing Yang
- Department of Gastroenterology, Qilu Hospital of Shandong University, Jinan 250012, China.
| | | | | | | | | | | |
Collapse
|
421
|
Abstract
Functional gastrointestinal disorders (FGIDs) commonly affect children and are associated with short- and long-term morbidity. Although the pathogenesis of pain-related FGIDs remains incompletely understood, most investigators agree on a multifactorial etiology and the presence of an altered brain-gut interaction. A continuous interplay of genetic and environmental factors appears to shape the development of the central and enteric nervous systems. The biopsychosocial model is the current operational framework for children with FGIDs, as it recognizes the interaction between social and environmental influences and psychological and physiologic processes. The biopsychosocial model proposes that specific permutations of genetic susceptibility, early life experiences, sociocultural issues, and coping mechanisms could explain the variability in clinical presentation and outcome among individuals.
Collapse
Affiliation(s)
- Ashis V Barad
- Children's Memorial Hospital, Northwestern University, 700 West Fullerton Avenue, Box 57, Chicago, IL 60614, USA.
| | | |
Collapse
|
422
|
Liu LS, Winston JH, Shenoy MM, Song GQ, Chen JDZ, Pasricha PJ. A rat model of chronic gastric sensorimotor dysfunction resulting from transient neonatal gastric irritation. Gastroenterology 2008; 134:2070-9. [PMID: 18448102 DOI: 10.1053/j.gastro.2008.02.093] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2007] [Revised: 02/23/2008] [Accepted: 02/28/2008] [Indexed: 02/08/2023]
Abstract
BACKGROUND & AIMS Although several pathophysiologic abnormalities have been noted in functional dyspepsia (FD), their pathogenesis is poorly understood. We hypothesized that chronic gastric hypersensitivity and gastric motor dysfunction seen in FD patients can be modeled in rats by transient gastric irritation during the neonatal period, a time of known neuronal vulnerability to long-term plasticity. METHODS Ten-day-old male rats received 0.2 mL 0.1% iodoacetamide (IA) in 2% sucrose daily by oral gavages for 6 days; controls received 2% sucrose. Rats in both groups were then followed to adulthood (8-10 weeks) at which point behavioral, visceromotor, and great splanchnic nerve responses to graded gastric balloon distention (GD; 20-80 mm Hg) and gastric motor function were tested. RESULTS IA-treated rats exhibited hypersensitivity to GD in a dose-dependent manner, as compared with the control group. The threshold of afferent nerve activation was lower and nerve responses to GD were significantly increased in IA-treated rats. Although IA-treated rats ingested food at a lower rate, gastric emptying was not significantly different between IA and control groups. However, gastric accommodation was significantly reduced in the IA group. No significant gastric pathology was seen in hypersensitive adult rats compared with controls. CONCLUSIONS These studies demonstrate that gastric irritation in the neonatal period can result in chronic gastric hypersensitivity and gastric motor dysfunction in adults even in the absence of significant detectable gastric pathology. Our results offer insight into the pathogenesis of chronic functional dyspepsia and provide a potential model for further study to this important clinical problem.
Collapse
Affiliation(s)
- Lian-Sheng Liu
- Division of Gastroenterology and Hepatology, Department of Medicine, Stanford University School of Medicine, Stanford, California 94305-5187, USA
| | | | | | | | | | | |
Collapse
|
423
|
Zohsel K, Hohmeister J, Flor H, Hermann C. Somatic pain sensitivity in children with recurrent abdominal pain. Am J Gastroenterol 2008; 103:1517-23. [PMID: 18510619 DOI: 10.1111/j.1572-0241.2008.01911.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Evidence is accumulating that recurrent abdominal pain (RAP) in children is associated with visceral hyperalgesia. However, it is not known whether somatic sensitivity is altered as well. Therefore, the aim of our study was to assess somatic pain sensitivity in children with RAP and healthy controls at the abdomen and a distal site (thenar). METHODS We examined 20 children with RAP (age 8-14) and 23 healthy control children (age 9-14). Heat and mechanical pain thresholds as well as measures of perceptual sensitization in response to repetitive mechanical or tonic thermal noxious stimulation were assessed. RESULTS At the abdominal site, pain sensitivity in children with RAP did not differ significantly when compared to controls. At the thenar, pain thresholds of children in the RAP group were not significantly different from control children. However, children with RAP showed less perceptual sensitization in response to tonic heat and repetitive mechanical stimuli (ps <or= 0.05) than controls. CONCLUSIONS We found no evidence for somatic hyperalgesia in RAP arguing against generalized hyperalgesia in these children. Somatic hypoalgesia at the thenar might either be related to a dysregulation of sensory processing and/or attentional avoidance of pain-related stimuli.
Collapse
Affiliation(s)
- Katrin Zohsel
- Department of Clinical and Cognitive Neuroscience, University of Heidelberg, Central Institute of Mental Health, Mannheim, Germany
| | | | | | | |
Collapse
|
424
|
Regulatory mechanism of electroacupuncture in irritable bowel syndrome: preventing MC activation and decreasing SP VIP secretion. Dig Dis Sci 2008; 53:1644-51. [PMID: 17999187 DOI: 10.1007/s10620-007-0062-4] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/22/2006] [Accepted: 10/04/2007] [Indexed: 02/06/2023]
Abstract
The efficacy of electroacupuncture (EA) for treating patients with diarrhea-predominant IBS has been confirmed in the authors' former research, but the regulatory mechanism of EA in IBS is still unknown. The aim of this study was to explore the relationship between the effect of EA on treating IBS rats and the activation and proliferation of mast cell (MC), the secretion of substance P(SP), and vasoactive intestinal polypeptide (VIP). The IBS rat model was set up with stress of binding limbs and colorectal distention. All rats were randomly assigned to four groups (Normal, Model, Tegaserod and EA). Hematoxylin and eosin staining has been used to observe the pathological change in the rats' colonic mucosa and an AWR scoring system has been applied to evaluate improvement of visceral hypersensitivity in various methods of the different groups. Toluidine blue improved method (TBI) and immunohistochemistry have also been involved in observations of mucous mast cells in the colon, change of c-fos positive cells, and secretion of SP, SPR, VIP, VIPR in the local colon. Firstly, the threshold of visceral sensitivity in the rats model with IBS was remarkably reduced (P < 0.01). The MC count in colonic mucosa and c-fos positive cells count increased significantly (P < 0.01) with positive correlation within each. Secondly, EA on ST-25 and Tegaserod pouring into the stomach can inhibit the proliferation and activation of MC in the colon and regulate secretion of SP, SPR, VIP, VIPR (P < 0.01, P < 0.05), while the effect of EA is obviously superior to Tegaserod. We concluded, firstly, that the abnormal proliferation and activation of mucous mast cells in the colon, and oversecretion of neuropeptides such as SP, VIP and their receptors could be one of key mechanisms of etiology of IBS. Secondly, the inhibition of activation and proliferation and the secretion of SP, VIP could be major effects of EA when treating rats with IBS.
Collapse
|
425
|
Zhou Q, Price DD, Verne NG. Reversal of visceral and somatic hypersensitivity in a subset of hypersensitive rats by intracolonic lidocaine. Pain 2008; 139:218-224. [PMID: 18486344 DOI: 10.1016/j.pain.2008.04.002] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2008] [Revised: 03/19/2008] [Accepted: 04/02/2008] [Indexed: 02/08/2023]
Abstract
Chronic abdominal pain is a common gastrointestinal symptom experienced by patients. We have previously shown that IBS patients with visceral hypersensitivity also have evidence of thermal hypersensitivity of the hand and foot that is reversed by rectal lidocaine jelly. We have also recently developed an animal model of chronic visceral and somatic hypersensitivity in rats treated with intracolonic trinitrobenzene sulfonic acid (TNBS). The objective of the current study was to determine the effects of intracolonic lidocaine on visceral/somatic hypersensitivity in TNBS-treated rats. A total of 20 hypersensitive rats received either 20mg intracolonic lidocaine (n=10) or saline jelly (n=10). In comparison to saline jelly, intracolonic lidocaine jelly reduced responses to nociceptive visceral/somatic stimuli in hypersensitive rats. The effects were present within 5-30 min after administration of lidocaine and lasted for 6h. Lidocaine had no effects on recovered rats or control rats that had originally been treated with intracolonic saline instead of TNBS. Local anesthetic blockade of peripheral impulse input from the colon reduces both visceral and somatic hypersensitivity in TNBS-treated rats, similar to results in IBS patients. The results provide further evidence that visceral and secondary somatic hypersensitivity in a subset of TNBS-treated rats reflect central sensitization mechanisms maintained by tonic impulse input from the colon. This study evaluates the reversal of visceral/somatic hypersensitivity in a subset of TNBS-treated rats with intracolonic lidocaine. This animal model may be used in the future to study the mechanisms of local anesthetic agents applied to the gut to reduce visceral pain.
Collapse
Affiliation(s)
- QiQi Zhou
- Division of Gastroenterology, Hepatology, & Nutrition, Ohio State University, 395 West 12th Avenue, Office Tower 288A, Columbus, OH 43210, USA Oral and Maxillofacial Surgery, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL, USA Department of Neuroscience, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL, USA North Florida/South Georgia VA Medical System, FL, USA
| | | | | |
Collapse
|
426
|
Chitkara DK, van Tilburg MAL, Blois-Martin N, Whitehead WE. Early life risk factors that contribute to irritable bowel syndrome in adults: a systematic review. Am J Gastroenterol 2008; 103:765-74; quiz 775. [PMID: 18177446 PMCID: PMC3856200 DOI: 10.1111/j.1572-0241.2007.01722.x] [Citation(s) in RCA: 196] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
BACKGROUND Irritable bowel syndrome (IBS) is a common disorder that occurs in adults. The natural history of symptoms and risk factors that contribute to IBS may begin in childhood. The aim of this systematic review was to determine what early life factors contribute to the development of IBS in adolescents and adults. METHODS A computer-assisted search of the PubMed database from 1966 to 2007 was performed. The selection criteria were: (a) studies conducted in adolescents or adults with IBS that (b) investigate premorbid factors occurring specifically during the childhood period and are (c) associated with the outcomes of symptoms, quality of life, health-care utilization, and interferences with work or disability. RESULTS Twenty-five articles met inclusion criteria. The studies were categorized into articles examining the persistence of childhood gastrointestinal symptoms into adulthood, affluent childhood socioeconomic status and adult IBS, infantile and childhood trauma associated with the development of adult IBS, and social learning of illness behavior as predictors of adult IBS. CONCLUSION Pediatricians should be aware of potentially modifiable childhood risk factors and should consider interventions such as early symptom management of recurrent functional abdominal pain with cognitive therapies and parent education about social learning of illness behavior. Early treatment may have a long-term impact. Research examining the effect of affluent childhood socioeconomic status and early childhood trauma in the evolution of functional gastrointestinal disorders may help identify causative factors of IBS.
Collapse
Affiliation(s)
- Denesh K. Chitkara
- UNC Center for Functional GI and Motility Disorders, University of
North Carolina School of Medicine Chapel Hill, NC
| | - Miranda A. L. van Tilburg
- UNC Center for Functional GI and Motility Disorders, University of
North Carolina School of Medicine Chapel Hill, NC
| | - Nannette Blois-Martin
- UNC Center for Functional GI and Motility Disorders, University of
North Carolina School of Medicine Chapel Hill, NC
| | - William E. Whitehead
- UNC Center for Functional GI and Motility Disorders, University of
North Carolina School of Medicine Chapel Hill, NC
| |
Collapse
|
427
|
La JH, Sung TS, Kim HJ, Kim TW, Kang TM, Yang IS. Peripheral corticotropin releasing hormone mediates post-inflammatory visceral hypersensitivity in rats. World J Gastroenterol 2008; 14:731-6. [PMID: 18205263 PMCID: PMC2684000 DOI: 10.3748/wjg.14.731] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate whether peripheral corticotropin releasing hormone (CRH), which is up-regulated in intestinal inflammation, mediates the post-inflammatory visceral hypersensitivity in a rat model of colitis.
METHODS: We measured mucosal myeloperoxidase (MPO) activity as a marker of inflammation, plasma CRH level, and abdominal withdrawal reflex (AWR) to colorectal distension as a visceral nociceptive response at 2, 7 and 14 d after the induction of colitis with 4% acetic acid.
RESULTS: Colonic inflammation, quantified by MPO activity, significantly increased on d 2 and subsided thereafter, which indicated a resolution of inflammation within 7 d. On the contrary, plasma CRH level and AWR score were increased on d 2, remained high on d 7, and returned to control level on d 14. Intraperitoneal injection of a CRH antagonist, astressin (30 &mgr;g/kg), significantly attenuated the post-inflammatory visceral hypersensitivity on d 7. Furthermore, intraperitoneal administration of CRH (3 and 10 &mgr;g/kg) mimicked the post-inflammatory visceral hypersensitivity in naive rats.
CONCLUSION: These results suggest that increased peripheral CRH mediates the enhanced visceral nociception in rats recovered from experimental colitis.
Collapse
|
428
|
Zhou Q, Price DD, Caudle RM, Verne GN. Visceral and somatic hypersensitivity in TNBS-induced colitis in rats. Dig Dis Sci 2008; 53:429-35. [PMID: 17703363 PMCID: PMC2807888 DOI: 10.1007/s10620-007-9881-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/14/2007] [Accepted: 05/14/2007] [Indexed: 12/30/2022]
Abstract
Inflammation of visceral structures in rats has been shown to produce visceral/somatic hyperalgesia. Our objectives were to determine if trinitrobenzene sulfonic acid (TNBS) induced colitis in rats leads to visceral/somatic hypersensitivity. Male Sprague-Dawley rats (200-250 g) were treated with 20 mg of TNBS in 50% ethanol (n = 40) or an equivalent volume of ethanol (n = 40) or saline (n = 25) via the colon. Colonic distension, Von Frey, Hargreaves, and tail reflex tests were used to evaluate for visceral, mechanical, and thermal sensitivity. The rats demonstrated visceral hypersensitivity at 2-28 days following TNBS administration (P < 0.0001). The ethanol-treated rats also demonstrated visceral hypersensitivity that resolved after day 14. TNBS-treated rats demonstrated somatic hypersensitivity at days 14-28 (P < 0.0001) in response to somatic stimuli of the hind paw. TNBS colitis is associated with visceral and somatic hypersensitivity in areas of somatotopic overlap. This model of colitis should allow further investigation into the mechanisms of visceral and somatic hypersensitivity.
Collapse
Affiliation(s)
- QiQi Zhou
- Department of Medicine, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL
| | - Donald D. Price
- Department of Oral and Maxillofacial Surgery, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL
- Department of Neuroscience, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL
| | - Robert M. Caudle
- Department of Oral and Maxillofacial Surgery, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL
- Department of Neuroscience, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL
| | - G. Nicholas Verne
- Department of Medicine, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL
- North Florida/South Georgia VA Medical System, USA
| |
Collapse
|
429
|
Zhang GH, Sweitzer SM. Neonatal morphine enhances nociception and decreases analgesia in young rats. Brain Res 2008; 1199:82-90. [PMID: 18267316 DOI: 10.1016/j.brainres.2007.12.043] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2007] [Revised: 12/19/2007] [Accepted: 12/20/2007] [Indexed: 01/19/2023]
Abstract
The recognition of the impact of neonatal pain experience on subsequent sensory processing has led to the increased advocacy for the use of opioids for pain relief in infants. However, following long-term opioid exposure in intensive care units more than 48% of infants exhibited behaviors indicative of opioid abstinence syndrome, a developmentally equivalent set of behaviors to opioid withdrawal as seen in adults. Little is known about the long-term influence of repeated neonatal morphine exposure on nociception and analgesia. To investigate this, we examined mechanical and thermal nociception on postnatal days 11, 13, 15, 19, 24, 29, 39 and 48 following subcutaneous administration of morphine (3 mg/kg) once daily on postnatal days 1-9. The cumulative morphine dose-response was assessed on postnatal days 20 and 49, and stress-induced analgesia was assessed on postnatal days 29 and 49. Both basal mechanical and thermal nociception in neonatal, morphine-exposed rats were significantly lower than those in saline-exposed, handled-control rats and naive rats until P29. A rightward-shift of cumulative dose-response curves for morphine analgesia upon chronic neonatal morphine was observed both on P20 and P49. The swim stress-induced analgesia was significantly decreased in neonatal morphine-exposed rats on P29, but not on P49. These data indicate that morphine exposure equivalent to the third trimester of gestation produced prolonged pain hypersensitivity, decreased morphine antinociception, and decreased stress-induced analgesia. The present study illustrates the need to examine the long-term influence of prenatal morphine exposure on pain and analgesia in the human pediatric population.
Collapse
Affiliation(s)
- Guo Hua Zhang
- Department of Pharmacology, Physiology and Neuroscience, University of South Carolina School of Medicine, Columbia, SC 29208, USA
| | | |
Collapse
|
430
|
Zhou Q, Nicholas Verne G. NMDA Receptors and Colitis: Basic Science and Clinical Implications. ACTA ACUST UNITED AC 2008; 10:33-43. [PMID: 20574552 DOI: 10.3727/154296108783994013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
During the last decade, research focusing primarily on alterations in the peripheral and central nervous system has improved our understanding of the pathophysiological mechanisms of chronic visceral pain. These studies have demonstrated significant physiological changes following injury to the viscera in the firing patterns of both primary afferent neurons that transmit nociceptive information from the viscera and in central neurons that process the nociceptive information. A number of receptors, neurotransmitters, cytokines, and second messenger systems in these neurons have been implicated in the enhancement of visceral nociception. N-methyl-d-aspartic acid (NMDA) receptors play an important role in chronic visceral pain and hypersensitivity that is present in the setting of colonic inflammation. NMDA receptors are found in the peripheral nervous system as well as the central terminal of primary afferent neurons and have been shown to play an important role in regulating the release of nociceptive neurotransmitters. Recent work has demonstrated the presence of NMDA receptors in the enteric nervous system. In this article, we will discuss more recent evidence of the role of NMDA receptors in visceral pain associated with colitis.
Collapse
Affiliation(s)
- Qiqi Zhou
- Department of Medicine, University of Florida Colleges of Medicine, Gainesville, FL, USA
| | | |
Collapse
|
431
|
Hind paw incision in the rat produces long-lasting colon hypersensitivity. THE JOURNAL OF PAIN 2007; 9:246-53. [PMID: 18088562 DOI: 10.1016/j.jpain.2007.10.017] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2007] [Revised: 10/19/2007] [Accepted: 10/23/2007] [Indexed: 12/21/2022]
Abstract
UNLABELLED Visceral injury has been shown to alter somatic sensitivity, but little is known about the effect of somatic insult on the viscera. In the present study, we examined (1) the effect of colon inflammation on somatic sensitivity and (2) the affect of hind paw incision on colon sensitivity. After intracolonic administration of trinitrobenzene sulfonic acid (TNBS) or zymosan, visceromotor responses to colorectal distension were increased to post-treatment day 8. Mechanical withdrawal thresholds in the hind paw were decreased in TNBS- and in zymosan-treated rats until post-intracolonic treatment day 2. There was no change in hind paw heat withdrawal latency in either group. Plantar incision of the hind paw resulted in a decrease in both hind paw mechanical withdrawal threshold and heat withdrawal latency and significantly increased the visceromotor response to colorectal distension from postincision days 1 to 8. The colon hypersensitivity was of longer duration than hyperalgesia at the site of hind paw incision. These results support the hypothesis that somatic injury and visceral inflammation can alter central processing of visceral and somatic inputs, respectively. PERSPECTIVE Surgical procedures are common and typically associated with hyperalgesia at and around the site of incision. This report establishes in a model of postsurgical pain and hyperalgesia that a long-lasting visceral hypersensitivity may also accompany postsurgical hyperalgesia.
Collapse
|
432
|
Mechanisms of acupuncture analgesia: Effective therapy for musculoskeletal pain? Curr Rheumatol Rep 2007; 9:473-81. [DOI: 10.1007/s11926-007-0077-z] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
433
|
Ohashi K, Kawai M, Ninomiya N, Taylor C, Kurebayashi Y. Effect of a New α 2δ Ligand PD-217014 on Visceral Hypersensitivity Induced by 2,4,6-Trinitrobenzene Sulfonic Acid in Rats. Pharmacology 2007; 81:144-50. [DOI: 10.1159/000110737] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2007] [Accepted: 08/20/2007] [Indexed: 11/19/2022]
|
434
|
LaPrairie JL, Murphy AZ. Female rats are more vulnerable to the long-term consequences of neonatal inflammatory injury. Pain 2007; 132 Suppl 1:S124-S133. [PMID: 17904745 PMCID: PMC2121098 DOI: 10.1016/j.pain.2007.08.010] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2007] [Revised: 08/06/2007] [Accepted: 08/10/2007] [Indexed: 02/06/2023]
Abstract
Premature infants are routinely exposed to invasive medical procedures during neonatal intensive care treatment that are largely performed in the absence of anesthetics or analgesics. Data collected to date suggest that exposure to early insult during this time of increased plasticity alters the development of the CNS and influences future pain responses. As previous studies examining the impact of neonatal injury on nociception have been conducted primarily in males, the potential adverse effects on females are not known. Therefore, the present studies were conducted to determine whether neonatal injury differentially impacts male and female sensory thresholds in adulthood. A short lasting inflammatory response was evoked in male and female rats on the day of birth with an injection of carrageenan (CGN; 1% or 2%) into the right hindpaw. Nociceptive thresholds were assessed using a noxious thermal stimulus at both adolescence (P40) and adulthood (P60). A more persistent inflammation was subsequently evoked in adult rats with an intraplantar injection of Complete Freund's adjuvant (CFA). Neonatally injured females exhibited significantly greater hypoalgesia at P60, and displayed enhanced inflammatory hyperalgesia following re-injury in adulthood compared to neonatally injured males and controls. These results demonstrate that the long-term adverse effects of neonatal injury are exacerbated in females, and may contribute to the higher prevalence, severity and duration of pain syndromes noted in women compared to men.
Collapse
Affiliation(s)
- Jamie L LaPrairie
- Department of Biology, Center for Behavioral Neuroscience, Georgia State University, 24 Peachtree Center Ave, 402 Kell Hall, Atlanta, GA 30303-3088, USA
| | | |
Collapse
|
435
|
Chung EKY, Zhang XJ, Xu HX, Sung JJY, Bian ZX. Visceral hyperalgesia induced by neonatal maternal separation is associated with nerve growth factor-mediated central neuronal plasticity in rat spinal cord. Neuroscience 2007; 149:685-95. [PMID: 17913374 DOI: 10.1016/j.neuroscience.2007.07.055] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2007] [Revised: 07/12/2007] [Accepted: 07/18/2007] [Indexed: 12/11/2022]
Abstract
Neonatal maternal separation (NMS) has been shown to trigger alterations in neuroendocrine, neurochemical and sensory response to nociceptive stimuli along the brain-gut axis. These alterations may be the result of a cascade of events that are regulated by neurotrophic factors. Nerve growth factor (NGF), a member of the neurotrophin family, is essential for the development and maintenance of sensory neurons and for the formation of central pain circuitry. The present study aimed to investigate whether NMS causes changes in neuronal plasticity and the relationship of these changes in plasticity with the expression of NGF and its high affinity tyrosine kinase receptor A (TrkA) in the lumbosacral spinal cord in adult rats. Male Wistar rat pups were either subjected to 180 min daily of NMS or not handled (NH) for 13 consecutive days. The expression of NGF and TrkA was examined in NH and NMS rats with or without colorectal distention (CRD) as determined by Western blot analysis and immunohistochemistry. The present results of Western blot analysis indicated NMS and CRD have a significant effect on NGF protein level in the lumbosacral spinal cord of rats. Assessments of optical densities revealed that NMS enhanced TrkA-ir fiber densities in laminae I-III and laminae V-VI of rats in both conditions with or without CRD. Double immunofluorescence revealed that TrkA co-expressed with calcitonin gene-related peptide (CGRP) in afferent fibers, while no significant difference in terms of the intensity of TrkA-ir in these fibers was found among groups. Quantitative analysis of TrkA-ir neurons indicated a significant interactive effect of NMS and CRD on the mean number of TrkA-ir neurons in laminae V-VI of rats, in which significant difference was found between NMS+CRD and NH+CRD. Double immunofluorescence of TrkA and Fos showed that CRD has a significant effect on TrkA expression in Fos-positive neurons in laminae V-VI and lamina X of rats, while no significant difference was found between NMS+CRD and NH+CRD. These results demonstrate that NMS induced alterations in NGF protein level and TrkA expression in adult rat spinal cord and indicate that NGF is a crucial mediator for the changes in neuronal plasticity that occur in NMS-induced visceral hyperalgesia.
Collapse
Affiliation(s)
- E K Y Chung
- School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong SAR, China.
| | | | | | | | | |
Collapse
|
436
|
Barreau F, Ferrier L, Fioramonti J, Bueno L. New insights in the etiology and pathophysiology of irritable bowel syndrome: contribution of neonatal stress models. Pediatr Res 2007; 62:240-5. [PMID: 17622962 DOI: 10.1203/pdr.0b013e3180db2949] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Irritable bowel syndrome (IBS) is one of the most common gastrointestinal disorders, characterized by abdominal pain and disturbed defecation that cannot be explained by structural abnormalities. Although IBS symptoms (visceral pain, increased gut permeability, motility alterations) are clearly established, the etiology of this pathology is loosely understood. Nevertheless, clinical studies have reported that some early abuse (physical and psychological) is often associated with IBS development. Thus, loss and separation in the family during childhood may contribute to the IBS development. The recent development of animal models has pointed out the importance of early traumatic experiences in favoring the occurrence of IBS in adult life. Among these different models, neonatal maternal deprivation (NMD), neonatal colonic irritation (inflammatory stimuli), and neonatal colonic pain (rectal distension) have been described to mimic some cardinal features of IBS. The purpose of this review is 3-fold. First, to present the different neonatal stress models. Second, to review the literature on the influence of these early traumatic experiences on the gastrointestinal tract disturbances observed in adult life. Finally, we will also present the mediators and mechanisms involved in gut dysfunction triggered by NMD and probably in IBS.
Collapse
Affiliation(s)
- Frederick Barreau
- INSERM U843, Inflammation intestinale chez l'enfant, Université Paris 7, Hôpital Robert Debré, F-75019 Paris, France.
| | | | | | | |
Collapse
|
437
|
Smith C, Nordstrom E, Sengupta JN, Miranda A. Neonatal gastric suctioning results in chronic visceral and somatic hyperalgesia: role of corticotropin releasing factor. Neurogastroenterol Motil 2007; 19:692-9. [PMID: 17640185 DOI: 10.1111/j.1365-2982.2007.00949.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Abstract Gastric suctioning is common in neonatal intensive care units. Studies suggest that gastric suctioning in premature infants may play a role in the development of visceral hyperalgesia. We hypothesized that repeated orogastric suctioning during the neonatal period results in chronic alterations in visceral and somatic sensation through a corticotropin-releasing factor mediated mechanism. Neonatal male Long Evans rats (n = 13) received daily orogastric suctioning for 10 days starting at postnatal day two (P2). Control rats (n = 15) were handled similarly without orogastric suction. A second study group was subjected to a similar protocol, only with pre-emptive administration of a CRF1 receptor antagonist (antalarmin, 20 mg/kg, IP) (n = 8). The control group received vehicle only (n = 8). An additional group was given antalarmin without suctioning (n = 5). After these rats grew to adulthood (PN 60), a visceromotor response to graded colorectal distension was recorded (10-80 mmHg, 30s, 180s inter-stimulus intervals) to assess changes in visceral sensitivity. Paw withdrawal latency to noxious heat applied to the hind paws was measured to assess changes in cutaneous sensitivity. Orogastric suctioning during the neonatal period results in global chronic somatic and visceral hyperalgesia in adult rats. Visceral hyperalgesia is prevented by pre-emptive administration of the CRF1 receptor antagonist, antalarmin.
Collapse
Affiliation(s)
- C Smith
- Department of Pediatrics, Medical College of Wisconsin, 8701 Watertown Plank Road, Milwaukee, WI 53226, USA
| | | | | | | |
Collapse
|
438
|
Moshiree B, Price DD, Robinson ME, Gaible R, Verne GN. Thermal and visceral hypersensitivity in irritable bowel syndrome patients with and without fibromyalgia. Clin J Pain 2007; 23:323-30. [PMID: 17449993 DOI: 10.1097/ajp.0b013e318032e496] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder characterized by both visceral and somatic hyperalgesia, producing a similar effect seen with the central hypersensitivity mechanism in fibromyalgia (FM). OBJECTIVES The aim of the current study was to compare magnitudes of visceral and thermal hypersensitivity in IBS patients and FM patients with IBS (FM+IBS) compared with healthy controls. METHODS Female patients with IBS (n=12), FM+IBS (n=12), and control participants (n=13) rated pain intensity to hot water immersion (45 and 47 degrees C) of the hand/foot and to phasic distension of the rectum (35, 55 mm Hg) on a Mechanical Visual Analog Scale. The data were analyzed with 3 separate 1-way analyses of variance with post hoc Tukey tests. RESULTS For both thermal and visceral stimuli, the control group had lower pain ratings than either the IBS or FM+IBS groups (P<0.001). IBS patients rated rectal distension as more painful than the FM+IBS group (P=0.005). During hot water immersion of the foot, the FM+IBS group had higher pain ratings than the IBS group (P<0.001). During hand immersion, FM+IBS and IBS patients did not significantly differ in their pain intensity ratings (P=0.4). CONCLUSIONS FM+IBS patients show greater thermal hypersensitivity compared with IBS patients. However, IBS patients exhibit higher pain ratings to rectal distension compared with FM+IBS patients. This data suggests that regions of primary and secondary hyperalgesia are dependent on the primary pain complaint.
Collapse
Affiliation(s)
- Baharak Moshiree
- Department of Medicine, University of Florida Colleges of Medicine, Dentistry, Public Health and Health Professions, Gainesville, FL 32610-0214, USA
| | | | | | | | | |
Collapse
|
439
|
Jones RCW, Otsuka E, Wagstrom E, Jensen CS, Price MP, Gebhart GF. Short-term sensitization of colon mechanoreceptors is associated with long-term hypersensitivity to colon distention in the mouse. Gastroenterology 2007; 133:184-94. [PMID: 17553498 DOI: 10.1053/j.gastro.2007.04.042] [Citation(s) in RCA: 108] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/12/2006] [Accepted: 04/05/2007] [Indexed: 01/12/2023]
Abstract
BACKGROUND & AIMS Using a mouse model that reproduces major features of irritable bowel syndrome (long-lasting colon hypersensitivity without inflammation), we examined the contributions of 2 proteins, transient receptor potential vanilloid 1 (TRPV1) and acid-sensing ion channel 3 (ASIC3), on development of behavioral hypersensitivity and assessed the function of colon mechanoreceptors of hypersensitive mice. METHODS Visceral nociceptive behavior was measured as the visceromotor response (VMR) to colorectal distention (CRD) before and after intracolonic treatment with zymosan or saline. Colon pathology was assessed in parallel experiments by quantifying myeloperoxidase activity, intralumenal pH, and tissue histology. Electrophysiologic experiments were performed on naïve and zymosan-treated hypersensitive mice using an in vitro colon-pelvic nerve preparation. RESULTS Zymosan, but not saline, produced significant and persistent increases in the VMRs of control mice; zymosan produced nonsignificant increases in the VMRs in TRPV1 and ASIC3 knockout mice. Colon myeloperoxidase activity and pH were unaffected by either CRD or intracolonic treatments. Pelvic nerve mechanoreceptors recorded from zymosan-treated or naïve mice had similar sensitivity to stretch of the colon. When applied acutely, zymosan sensitized muscular/mucosal mechanoreceptors in both naïve and hypersensitive mice. CONCLUSIONS Zymosan produced sensitization of colon mechanoreceptors acutely in vitro and chronic (>or=7 weeks) behavioral hypersensitivity in the absence of inflammation. The behavioral hypersensitivity was partially dependent on both TRPV1 and ASIC3 because deletions of either of these genes blunted zymosan's effect, suggesting that these proteins may be important peripheral mediators for development of functional (ie, noninflammatory) visceral hypersensitivity.
Collapse
Affiliation(s)
- R Carter W Jones
- Medical Scientist Training Program, The University of Iowa, Iowa City, Iowa, USA
| | | | | | | | | | | |
Collapse
|
440
|
Chung EKY, Zhang X, Li Z, Zhang H, Xu H, Bian Z. Neonatal maternal separation enhances central sensitivity to noxious colorectal distention in rat. Brain Res 2007; 1153:68-77. [PMID: 17434464 DOI: 10.1016/j.brainres.2007.03.047] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2006] [Revised: 03/09/2007] [Accepted: 03/18/2007] [Indexed: 12/28/2022]
Abstract
Psychological stress experienced in early life plays an important role in the development of visceral hyperalgesia in irritable bowel syndrome (IBS). Neonatal maternal separation has been shown to trigger a long-term alternation in stress-induced responses to visceral nociceptive stimuli in rats. The aim of the present study was to show a direct evidence of stress-induced alteration in central neuronal responses to colorectal distention (CRD) in rats by a quantitative study of c-fos expression in relevant brain structures. Male Wistar rat pups were subjected to 180-min daily neonatal maternal separation (NMS) for 13 consecutive days (from PND 2 to PND 14). The expression of c-fos was examined by using immunohistochemistry. Increased c-fos expression was observed, for the first time, in the cingulate cortex (3-fold) in NMS rats in comparison with the control group at basal condition. At noxious CRD (80 mm Hg), c-fos expression was induced in the supraspinal centers and in both the superficial (laminae I-II) and the deeper laminae (laminae V-VI and X) of the spinal cord in rats. Significantly more Fos-IR nuclei were found in the laminae I and II, and laminae V-VI of the lumbarsacral spinal cord, the paraventricular thalamic nucleus, the cingulate cortex, the amygdaloid central nucleus in NMS rats, but not in the solitary tract, the central medial thalamic nucleus, the ventromedial hypothalamic nucleus, and the periaquaductal gray. The present results indicate that NMS has sensitized the cingulate cortex and upregulated the activity of the ascending pathway at spinal level as well as the thalamo-cortico-amydala pathway to CRD. The upregulation and sensitization of these pathways may be responsible for the development of visceral hypersensitivity in IBS.
Collapse
Affiliation(s)
- Elaine K Y Chung
- School of Chinese Medicine, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China
| | | | | | | | | | | |
Collapse
|
441
|
Zhou Q, Price DD, Caudle RM, Verne GN. Visceral and somatic hypersensitivity in a subset of rats following TNBS-induced colitis. Pain 2007; 134:9-15. [PMID: 17481818 PMCID: PMC2807887 DOI: 10.1016/j.pain.2007.03.029] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2007] [Revised: 02/19/2007] [Accepted: 03/19/2007] [Indexed: 12/13/2022]
Abstract
BACKGROUND Chronic abdominal pain is one of the most common gastrointestinal symptoms experienced by patients. Visceral hypersensitivity has been shown to be a biological marker in many patients with chronic visceral pain. We have previously shown that IBS patients with visceral hypersensitivity also have evidence of thermal hyperalgesia of the hand/foot. OBJECTIVE The objective of the current study was to develop an animal model of chronic visceral and somatic hypersensitivity in rats treated with intracolonic trinitrobenzene sulfonic acid. DESIGN Male Sprague-Dawley rats (200-250g) were treated with either 20mg/rat trinitrobenzene sulfonic acid (TNBS, Sigma Chemical Co.) in 50% ethanol (n=75), an equivalent volume of 50% ethanol (n=20) or an equivalent volume of saline (n=20). The agents were delivered with a 24-gauge catheter inserted into the lumen of the colon. Mechanical and thermal behavioral tests were performed using an automated von Frey and Hargreaves device to evaluate somatic hyperalgesia. Colonic distension was performed using an automated distension device to evaluate visceral pain thresholds. All animals were tested 16weeks after TNBS treatment following complete resolution of the colitis. RESULTS At 16weeks, 24% of the treated rats (18/75 rats) still exhibited evidence of visceral as well as somatic hypersensitivity compared to saline- and ethanol-treated rats. CONCLUSION Transient colonic inflammation leads to chronic visceral and somatic hypersensitivity in a subset of rats. These findings are similar to the subset of patients who develop chronic gastrointestinal symptoms following enteric infection.
Collapse
Affiliation(s)
- QiQi Zhou
- Department of Medicine, Division of Gasteroenterology, Hepatology, and Nutrition, University of Florida Colleges of Medicine and Dentistry, 1600 SW Archer Road, HD 602, PO Box 100214, Gainesville, FL 32610-0214, USA
| | - Donald D. Price
- Department of Oral and Maxillofacial Surgery, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL, USA
- Department of Neuroscience, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL, USA
| | - Robert M. Caudle
- Department of Oral and Maxillofacial Surgery, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL, USA
- Department of Neuroscience, University of Florida Colleges of Medicine and Dentistry, Gainesville, FL, USA
| | - G. Nicholas Verne
- Department of Medicine, Division of Gasteroenterology, Hepatology, and Nutrition, University of Florida Colleges of Medicine and Dentistry, 1600 SW Archer Road, HD 602, PO Box 100214, Gainesville, FL 32610-0214, USA
- North Florida/South Georgia VA Medical System, USA
- Corresponding author. Department of Medicine, Division of Gasteroenterology, Hepatology, and Nutrition, University of Florida Colleges of Medicine and Dentistry, 1600 SW Archer Road, HD 602, PO Box 100214, Gainesville, FL 32610-0214, USA. Tel.: +1 352 392 2877; fax: +1 352 392 3618. (G.N. Verne)
| |
Collapse
|
442
|
Abstract
The investigative evidence and emerging concepts in neurogastroenterology implicate dysfunctions at the levels of the enteric and central nervous systems as underlying causes of the prominent symptoms of many of the functional gastrointestinal disorders. Neurogastroenterological research aims for improved understanding of the physiology and pathophysiology of the digestive subsystems from which the arrays of functional symptoms emerge. The key subsystems for defecation-related symptoms and visceral hyper-sensitivity are the intestinal secretory glands, the musculature and the nervous system that controls and integrates their activity. Abdominal pain and discomfort arising from these systems adds the dimension of sensory neurophysiology. This review details current concepts for the underlying pathophysiology in terms of the physiology of intestinal secretion, motility, nervous control, sensing function, immuno-neural communication and the brain-gut axis.
Collapse
|
443
|
Ren TH, Wu J, Yew D, Ziea E, Lao L, Leung WK, Berman B, Hu PJ, Sung JJY. Effects of neonatal maternal separation on neurochemical and sensory response to colonic distension in a rat model of irritable bowel syndrome. Am J Physiol Gastrointest Liver Physiol 2007; 292:G849-56. [PMID: 17110521 DOI: 10.1152/ajpgi.00400.2006] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Early life stress has been implicated as a risk factor for irritable bowel syndrome (IBS). We studied the effect of neonatal maternal separation on the visceromotor response and the expression of c-fos, 5-HT, and its receptors/transporters along the brain-gut axis in an animal model of IBS. Male neonatal Sprague-Dawley rats were randomly assigned to a 3-h daily maternal separation (MS) or nonhandling (NH) on postnatal days 2-21. Colorectal balloon distention (CRD) was performed for assessment of abdominal withdrawal reflex as a surrogate marker of visceral pain. Tissues from dorsal raphe nucleus in midbrain, lumbar-sacral cord, and distal colon were harvested for semiquantitative analysis of c-fos and 5-HT. The expression of 5-HT expression, 5-HT3 receptors, and 5-HT transporter were analyzed by RT-PCR. Pain threshold was significantly lower in MS than NH rats. The abdominal withdrawal reflex score in response to CRD in MS rats was significantly higher with distension pressures of 40, 60, and 80 mmHg. In MS rats, the number of c-fos-like immunoreactive nuclei at dorsal horn of lumbar-sacral spinal cord increased significantly after CRD. 5-HT content in the spinal cord of MS rats was significant higher. In the colon, both 5-HT-positive cell number and 5-HT content were comparable between MS and NH groups before CRD. Post-CRD only MS rats had significant increase in 5-HT content. Protein and mRNA expression levels of 5-HT3 receptors and 5-HT transporter were similar in MS and NH rats. Neonatal maternal separation stress predisposes rats to exaggerated neurochemical responses and visceral hyperalgesia in colon mimicking IBS.
Collapse
Affiliation(s)
- Tian-Hua Ren
- Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, NT, Hong Kong
| | | | | | | | | | | | | | | | | |
Collapse
|
444
|
Hauer JM, Wical BS, Charnas L. Gabapentin successfully manages chronic unexplained irritability in children with severe neurologic impairment. Pediatrics 2007; 119:e519-22. [PMID: 17272610 DOI: 10.1542/peds.2006-1609] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Neurologically impaired children have an increased frequency of recurrent pain and irritability that persist in some despite comprehensive evaluation and management of possible pain sources. We hypothesized that visceral hyperalgesia was a source of chronic unexplained irritability and report the outcome of gabapentin treatment in 9 severely neurologically impaired children. Caregivers reported marked improvement after treatment ranging from 3 months to 3 years. Nystagmus in 1 child was the only noted adverse effect. Visceral hyperalgesia may be a source of unexplained irritability in the neurologically impaired child. Symptoms may improve with gabapentin treatment.
Collapse
Affiliation(s)
- Julie M Hauer
- University of Minnesota, Department of Pediatrics, MMC 391, 420 Delaware St SE, Minneapolis, MN 55455, USA.
| | | | | |
Collapse
|
445
|
Sayuk GS, Elwing JE, Lustman PJ, Clouse RE. Predictors of premature antidepressant discontinuation in functional gastrointestinal disorders. Psychosom Med 2007; 69:173-81. [PMID: 17289822 DOI: 10.1097/psy.0b013e318031391d] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVES To identify factors responsible for premature antidepressant discontinuation that would assist in designing management strategies for patients with functional gastrointestinal disorders. Antidepressants are being used increasingly to manage patients with functional gastrointestinal disorders; poor patient adherence to treatment regimens, particularly in the period shortly after antidepressant initiation, is common and interferes with success. METHODS Clinical records were reviewed from 172 outpatients who attended a university-based practice and who had been prescribed antidepressants to manage their functional gastrointestinal symptoms. Survival analysis methods were used to determine independent predictors of premature antidepressant discontinuation (within 6 months of initiation). Logistic regression analyses were used to see if the same predictors were responsible for side effects or poor treatment response. RESULTS Premature antidepressant discontinuation occurred in 41 (23.8%) subjects. Somatization features (state or trait) and history of depression or an anxiety disorder were the most significant predictors of premature discontinuation (p < or = .01 for each). Advancing age and female sex also were independent predictors (p < .05 for each). Somatization features and psychiatric illness were each linked to poor treatment response, whereas somatization features most consistently were associated with antidepressant side effects. CONCLUSIONS Failure to maintain treatment occurs in nearly a quarter of outpatients given antidepressants for functional gastrointestinal disorders. Somatization features and history of depression or anxiety most significantly interfered with treatment by predicting side effects, poor treatment response, and premature antidepressant discontinuation. Management algorithms should include specific strategies targeted at patients with these risk factors for poor treatment adherence.
Collapse
Affiliation(s)
- Gregory S Sayuk
- Division of Gastroenterology, Washington University School of Medicine, St. Louis, MO 63110, USA
| | | | | | | |
Collapse
|
446
|
Winston J, Shenoy M, Medley D, Naniwadekar A, Pasricha PJ. The vanilloid receptor initiates and maintains colonic hypersensitivity induced by neonatal colon irritation in rats. Gastroenterology 2007; 132:615-27. [PMID: 17258716 DOI: 10.1053/j.gastro.2006.11.014] [Citation(s) in RCA: 170] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/05/2006] [Accepted: 10/26/2006] [Indexed: 12/17/2022]
Abstract
BACKGROUND & AIMS Robust chemical or mechanical irritation of the colon of neonatal rats leads to chronic visceral hypersensitivity. The clinical and physiologic relevance of such noxious stimulation in the context of human irritable bowel syndrome is questionable. The aims of this study were to determine whether mild chemical irritation of the colon of neonatal rats produced persistent changes in visceral sensitivity and to evaluate the role of transient receptor potential vanilloid 1 (TRPV1) in the initiation and maintenance of visceral hypersensitivity. METHODS Ten-day-old rat pups received an intracolonic infusion of 0.5% acetic acid in saline. TRPV1 inhibitors were administered 30 minutes before acetic acid sensitization. Sensitivity of the colon to balloon distention (CRD) in adults was measured by grading their abdominal withdrawal reflex and electromyographic responses. In adult rats, TRPV1 antagonist was injected intraperitoneally 30 minutes before CRD. RESULTS Neonatal acetic acid treatment resulted in higher sensitivity to CRD in adult rats compared with controls in the absence of histopathologic signs of inflammation. Treatment of colons of adult rats with acetic acid did not produce persistent sensitization. Antagonism of the TRPV1 before neonatal administration of acetic acid and after established visceral hypersensitivity attenuated sensitivity to CRD. TRPV1 expression was increased in dorsal root ganglia-containing colon afferent neurons. CONCLUSIONS We have described a new model for persistent colonic sensory dysfunction following a transient noxious stimulus in the neonatal period and a potentially important role for TRPV1 in initiation and maintenance of persistent visceral hypersensitivity.
Collapse
Affiliation(s)
- John Winston
- Enteric Neuromuscular Disorders and Pain Laboratory, Division of Gastroenterology and Hepatology, Department of Internal Medicine, University of Texas Medical Branch, Galveston 77555-0764, USA
| | | | | | | | | |
Collapse
|
447
|
Abstract
Measurement of visceral sensitivity in animals is mainly based on 'pseudoaffective' responses, which are brain stem reflexes. For example, in female, but not male rats, acute partial restraint stress induces hypersensitivity to colorectal distension. Mucosal mast cell density increases in rats after nematode infection or maternal deprivation, and both also induce colon hypersensitivity. Significantly, the proximity between nerves and mast cells has been found to be increased in adult rats submitted to maternal deprivation. Protease activation of the proteinase-activated receptor-2 also increases visceral nociception in rats, suggesting that an increase in paracellular permeability may be the primum movens in several animal models of visceral hypersensitivity. Accumulating evidence suggests that sensitization of visceral afferents is not restricted to the presumed nociceptor population, suggesting that most of the mechanosensitive afferent population can contribute to visceral discomfort and pain. Other inflammation-produced changes (e.g. subunit composition of purine-gated P2X channels) in visceral sensory neurones may also contribute to visceral hypersensitivity. This article discusses use of in vivo strategies (and transgenic mouse models) to reveal putative roles in mechanosensitivity and sensitization for molecules not previously considered to have mechanosensory functions.
Collapse
Affiliation(s)
- J Fioramonti
- Neurogastroenterology and Nutrition Unit, INRA, Toulouse cedex, France.
| | | |
Collapse
|
448
|
Abstract
Visceral hypersensitivity (perception of gastrointestinal sensory events at a lower-than-normal threshold) is considered to be an important pathophysiological mechanism in the development of functional gastrointestinal disorders (FGIDs), such as irritable bowel syndrome, non-cardiac chest pain and functional dyspepsia. These disorders are associated with significant health care and socioeconomic costs due to factors such as repeated visits to consultants, hospitalizations and work absenteeism. Despite the presence of extensive evidence linking visceral hypersensitivity and FGIDs, the mechanism(s) underlying visceral hypersensitivity has not been fully elucidated. Suggested hypotheses include sensitization of afferent neurones, both at the level of the enteric and the (afferent) autonomic nervous system (peripheral sensitization), sensitization of spinal cord dorsal horn neurones (central sensitization) and psychosocial factors/psychiatric comorbidity influencing the processing of afferent signals at the level of the brain. Importantly, these hypotheses may be complementary rather than mutually exclusive. However, the degree to which each of these mechanisms contributes to the overall perception of visceral pain, and therefore the generation of symptoms, still remains unclear. This article discusses the mechanisms that may underlie visceral hypersensitivity, with reference to FGIDs. Understanding these mechanisms is essential in order to improve the diagnosis and treatment of patients with these disorders.
Collapse
Affiliation(s)
- P Anand
- Peripheral Neuropathy Unit, Department of Clinical Neuroscience, Imperial College London, London, UK
| | | | | | | |
Collapse
|
449
|
Gershon MD, Tack J. The serotonin signaling system: from basic understanding to drug development for functional GI disorders. Gastroenterology 2007; 132:397-414. [PMID: 17241888 DOI: 10.1053/j.gastro.2006.11.002] [Citation(s) in RCA: 1050] [Impact Index Per Article: 61.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/28/2006] [Accepted: 11/06/2006] [Indexed: 12/11/2022]
Abstract
Serotonin is an important gastrointestinal signaling molecule. It is a paracrine messenger utilized by enterochromaffin (EC) cells, which function as sensory transducers. Serotonin activates intrinsic and extrinsic primary afferent neurons to, respectively, initiate peristaltic and secretory reflexes and to transmit information to the central nervous system. Serotonin is also a neurotransmitter utilized by a system of long descending myenteric interneurons. Serotonin is synthesized through the actions of 2 different tryptophan hydroxylases, TpH1 and TpH2, which are found, respectively, in EC cells and neurons. Serotonin is inactivated by the serotonin reuptake transporter (SERT)-mediated uptake into enterocytes or neurons. The presence of many serotonin receptor subtypes enables selective drugs to be designed to therapeutically modulate gastrointestinal motility, secretion, and sensation. Current examples include tegaserod, a 5-HT(4) partial agonist, which has been approved for treatment of irritable bowel syndrome (IBS) with constipation in women and for chronic constipation in men and women. The 5-HT(3) antagonists, granisetron and ondansetron, are useful in combating the nausea associated with cancer chemotherapy, and alosetron is employed in the treatment of IBS with diarrhea. Serotonergic signaling abnormalities have also been putatively implicated in the pathogenesis of functional bowel diseases. Other compounds, for which efficacy has not been rigorously established, but which may have value, include tricyclic antidepressants and serotonin selective reuptake inhibitors to combat IBS, and 5-HT(1) agonists, which enhance gastric accommodation, to treat functional dyspepsia. The initial success encountered with serotonergic agents holds promise for newer and more potent insights and therapies of brain-gut disorders.
Collapse
Affiliation(s)
- Michael D Gershon
- Department of Pathology & Cell Biology, Columbia University, College of Physicians and Surgeons, 630 West 168th Street, New York, NY 10032, USA.
| | | |
Collapse
|
450
|
Affiliation(s)
- Chao Ma
- Yale University School of Medicine, New Haven, Connecticut, 06510, USA.
| |
Collapse
|