1
|
Li JJ, Ren WJ, Yin HY, Zhao YF, Tang Y. Underlying mechanisms for intestinal diseases arising from stress. Shijie Huaren Xiaohua Zazhi 2020; 28:617-627. [DOI: 10.11569/wcjd.v28.i14.617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Stress is an instinctive defense mechanism of the body in the competition for survival, but long-term or chronic stress will lead to systemic pathological manifestations. Intestinal diseases are closely related to pathological stress. This paper reviews the pathogenesis of intestinal diseases arising from stress.
Collapse
Affiliation(s)
- Jia-Jia Li
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, Sichuan Province, China,Key Laboratory of Sichuan Province for Acupuncture and Chronobiology, Chengdu 610075, Sichuan Province, China
| | - Wen-Jing Ren
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, Sichuan Province, China,Key Laboratory of Sichuan Province for Acupuncture and Chronobiology, Chengdu 610075, Sichuan Province, China
| | - Hai-Yan Yin
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, Sichuan Province, China,Key Laboratory of Sichuan Province for Acupuncture and Chronobiology, Chengdu 610075, Sichuan Province, China
| | - Ya-Fei Zhao
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, Sichuan Province, China,Key Laboratory of Sichuan Province for Acupuncture and Chronobiology, Chengdu 610075, Sichuan Province, China
| | - Yong Tang
- School of Acupuncture and Tuina, Chengdu University of Traditional Chinese Medicine, Chengdu 610075, Sichuan Province, China,Key Laboratory of Sichuan Province for Acupuncture and Chronobiology, Chengdu 610075, Sichuan Province, China
| |
Collapse
|
2
|
Larauche M, Moussaoui N, Biraud M, Bae W, Duboc H, Million M, Taché Y. Brain corticotropin-releasing factor signaling: Involvement in acute stress-induced visceral analgesia in male rats. Neurogastroenterol Motil 2019; 31:e13489. [PMID: 30298965 PMCID: PMC6347489 DOI: 10.1111/nmo.13489] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 09/14/2018] [Accepted: 09/17/2018] [Indexed: 02/06/2023]
Abstract
BACKGROUND Water avoidance stress (WAS) induces a naloxone-independent visceral analgesia in male rats under non-invasive conditions of monitoring. The objective of the study was to examine the role of brain CRF signaling in acute stress-induced visceral analgesia (SIVA). METHODS Adult male Sprague-Dawley rats were chronically implanted with an intracerebroventricular (ICV) cannula. The visceromotor response (VMR) to graded phasic colorectal distension (CRD: 10, 20, 40, 60 mm Hg, 20 seconds, 4 minutes intervals) was monitored using manometry. The VMR to a first CRD (baseline) was recorded 5 minutes after an ICV saline injection, followed 1 hour later by ICV injection of either CRF (30, 100, or 300 ng and 1, 3, or 5 μg/rat) or saline and a second CRD, 5 minutes later. Receptor antagonists against CRF1 /CRF2 (astressin-B, 30 μg/rat), CRF2 (astressin2 -B, 10 μg/rat), oxytocin (tocinoic acid, 20 μg/rat), or vehicle were injected ICV 5 minutes before CRF (300 ng/rat, ICV) or 15 minutes before WAS (1 hour). KEY RESULTS ICV CRF (100 and 300 ng) reduced the VMR to CRD at 60 mm Hg by -36.6% ± 6.8% and -48.7% ± 11.7%, respectively, vs baseline (P < 0.001), while other doses had no effect and IP CRF (10 µg/kg) induced visceral hyperalgesia. Astressin-B and tocinoic acid injected ICV induced hyperalgesia and prevented the analgesic effect of ICV CRF (300 ng/rat) and WAS, while astressin2 -B only blocked WAS-induced SIVA. CONCLUSIONS & INFERENCES These data support a role for brain CRF signaling via CRF2 in SIVA in a model of WAS and CRD likely mediated by the activation of brain oxytocin pathway.
Collapse
Affiliation(s)
- M. Larauche
- Department of Medicine, UCLA, G Oppenheimer Center for
Neurobiology of Stress and Resilience and CURE: Digestive Diseases Research Center,
Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of
Medicine, Los Angeles, CA, United States,VA Greater Los Angeles Healthcare System, Los Angeles, CA,
United States
| | - N. Moussaoui
- Department of Medicine, UCLA, G Oppenheimer Center for
Neurobiology of Stress and Resilience and CURE: Digestive Diseases Research Center,
Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of
Medicine, Los Angeles, CA, United States,VA Greater Los Angeles Healthcare System, Los Angeles, CA,
United States,Present address: Inserm U1048/I2MC Obesity Research
Laboratory, 1 avenue Jean Poulhès BP 84225 31432 Toulouse Cedex 4,
France
| | - M. Biraud
- Department of Medicine, UCLA, G Oppenheimer Center for
Neurobiology of Stress and Resilience and CURE: Digestive Diseases Research Center,
Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of
Medicine, Los Angeles, CA, United States,VA Greater Los Angeles Healthcare System, Los Angeles, CA,
United States,Present address: 1060 William Moore drive CVM Main
Building, RM C305, Raleigh, NC 27607, USA
| | - W.K. Bae
- Department of Medicine, UCLA, G Oppenheimer Center for
Neurobiology of Stress and Resilience and CURE: Digestive Diseases Research Center,
Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of
Medicine, Los Angeles, CA, United States,VA Greater Los Angeles Healthcare System, Los Angeles, CA,
United States,Present address: Department of Internal Medicine, Ilsan
Paik Hospital, Inje University College of Medicine, Goyang, Korea
| | - H. Duboc
- Department of Medicine, UCLA, G Oppenheimer Center for
Neurobiology of Stress and Resilience and CURE: Digestive Diseases Research Center,
Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of
Medicine, Los Angeles, CA, United States,VA Greater Los Angeles Healthcare System, Los Angeles, CA,
United States,Present address: CRI INSERM UMR 1149, University Paris
Diderot, Sorbonne Paris Cité and DHU Unity, APHP, F-75890 Paris, France
| | - M. Million
- Department of Medicine, UCLA, G Oppenheimer Center for
Neurobiology of Stress and Resilience and CURE: Digestive Diseases Research Center,
Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of
Medicine, Los Angeles, CA, United States,VA Greater Los Angeles Healthcare System, Los Angeles, CA,
United States
| | - Y. Taché
- Department of Medicine, UCLA, G Oppenheimer Center for
Neurobiology of Stress and Resilience and CURE: Digestive Diseases Research Center,
Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of
Medicine, Los Angeles, CA, United States,VA Greater Los Angeles Healthcare System, Los Angeles, CA,
United States
| |
Collapse
|
3
|
Nozu T, Miyagishi S, Kumei S, Nozu R, Takakusaki K, Okumura T. Metformin inhibits visceral allodynia and increased gut permeability induced by stress in rats. J Gastroenterol Hepatol 2019; 34:186-193. [PMID: 29966173 DOI: 10.1111/jgh.14367] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 06/06/2018] [Accepted: 06/17/2018] [Indexed: 12/23/2022]
Abstract
BACKGROUND AND AIM Metformin has been shown to have anti-cytokine property. Lipopolysaccharide (LPS)-induced or repeated water avoidance stress (WAS)-induced visceral allodynia and increased gut permeability were pro-inflammatory cytokine-dependent responses, which were considered to be animal models of irritable bowel syndrome (IBS). We hypothesized that metformin improves symptoms in the patients with IBS by attenuating these visceral changes and tested the hypothesis in rats. METHODS The threshold of the visceromotor response induced by colonic balloon distention was measured. Colonic permeability was determined in vivo by quantifying the absorbed Evans blue for 15 min spectrophotometrically. RESULTS Subcutaneously injected LPS (1 mg/kg) reduced the threshold of visceromotor response, and metformin (5-50 mg/kg for 3 days) intraperitoneally attenuated this response in a dose-dependent manner. Repeated WAS (1 h daily for 3 days) induced visceral allodynia, which was also blocked by metformin. The antinociceptive effect of metformin on the LPS-induced allodynia was reversed by compound C, an adenosine monophosphate-activated protein kinase inhibitor or NG -nitro-L-arginine methyl ester, a nitric oxide synthesis inhibitor but not modified by naloxone. Additionally, it was blocked by sulpiride, a dopamine D2 receptor antagonist, but domperidone, a peripheral dopamine D2 receptor antagonist, did not alter it. Metformin also blocked the LPS-induced or repeated WAS-induced increased colonic permeability. CONCLUSIONS Metformin attenuated the visceral allodynia and increased gut permeability in animal IBS models. These actions may be evoked via activation of adenosine monophosphate-activated protein kinase, nitric oxide, and central dopamine D2 pathways. These results indicate the possibility that metformin can be useful for treating IBS.
Collapse
Affiliation(s)
- Tsukasa Nozu
- Department of Regional Medicine and Education, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Saori Miyagishi
- Division of Gastroenterology and Hematology/Oncology, Department of Medicine, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Shima Kumei
- Department of General Medicine, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Rintaro Nozu
- Department of Regional Medicine and Education, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Kaoru Takakusaki
- Research Center for Brain Function and Medical Engineering, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Toshikatsu Okumura
- Division of Gastroenterology and Hematology/Oncology, Department of Medicine, Asahikawa Medical University, Asahikawa, Hokkaido, Japan.,Department of General Medicine, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| |
Collapse
|
4
|
Zhu S, Min L, Guo Q, Li H, Yu Y, Zong Y, Wang L, Li P, Gu J, Zhang S. Transcriptome and methylome profiling in a rat model of irritable bowel syndrome induced by stress. Int J Mol Med 2018; 42:2641-2649. [PMID: 30106160 PMCID: PMC6192760 DOI: 10.3892/ijmm.2018.3823] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Accepted: 08/09/2018] [Indexed: 12/13/2022] Open
Abstract
Irritable bowel syndrome (IBS) is a common gastrointestinal disorder that is associated with psychological stress. However, the full landscape of IBS-related epigenetic factors remains unveiled and needs to be elucidated. The water-avoidance stress (WAS) method was used to induce a rat IBS model. Each rat was monitored, and its defecation and behavior were recorded. Total colon RNA was isolated and subjected to Affymetrix GeneChip analysis. Reduced Representation Bisulfate Sequencing (RRBS) was applied to determine the genome-wide methylation pattern in both IBS and control rats. Rats with IBS egested a significantly increased amount of dry and loose stools compared with the control animals, without significant changes in body weight. Compared with the control group, 309 genes were upregulated and 224 genes were downregulated in the colon of the IBS rats. Notch signaling and focal adhesion were increased in the differentially expressed genes (DEGs). A total of 541 genes had significant lower methylation level and 626 genes had significantly higher methylation level in their promoter regions. Adherens junction and leukocyte transendothelial migration were enriched in the differentially methylated genes (DMGs). Few genes were identified in common in both DEGs and DMGs, suggesting that gene expression was not altered by promoter methylation. Reverse transcription-quantitative polymerase chain reaction validation revealed that the mRNA levels of SSX2IP, PARD3 and VCL were significantly downregulated in the IBS group, in accordance with hypermethylation of their promoters. In summary, the present study used a WAS-induced IBS rat model to provide transcriptome and methylome profiling. Most DEGs were associated with Notch signaling and focal adhesion, and only a few were altered by promoter methylation. The present results demonstrated that psychological stress could influence the integrity of the intestinal mucosa barrier and regulate inflammatory response.
Collapse
Affiliation(s)
- Shengtao Zhu
- Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, National Clinical Research Center for Digestive Disease, Beijing Digestive Disease Center, Beijing Key Laboratory for Precancerous Lesion of Digestive Disease, Beijing 100050, P.R. China
| | - Li Min
- Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, National Clinical Research Center for Digestive Disease, Beijing Digestive Disease Center, Beijing Key Laboratory for Precancerous Lesion of Digestive Disease, Beijing 100050, P.R. China
| | - Qingdong Guo
- Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, National Clinical Research Center for Digestive Disease, Beijing Digestive Disease Center, Beijing Key Laboratory for Precancerous Lesion of Digestive Disease, Beijing 100050, P.R. China
| | - Hengcun Li
- Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, National Clinical Research Center for Digestive Disease, Beijing Digestive Disease Center, Beijing Key Laboratory for Precancerous Lesion of Digestive Disease, Beijing 100050, P.R. China
| | - Yang Yu
- Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, National Clinical Research Center for Digestive Disease, Beijing Digestive Disease Center, Beijing Key Laboratory for Precancerous Lesion of Digestive Disease, Beijing 100050, P.R. China
| | - Ye Zong
- Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, National Clinical Research Center for Digestive Disease, Beijing Digestive Disease Center, Beijing Key Laboratory for Precancerous Lesion of Digestive Disease, Beijing 100050, P.R. China
| | - Liyong Wang
- Department of Biochemistry and Molecular Biology, Capital Medical University, Beijing 100050, P.R. China
| | - Peng Li
- Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, National Clinical Research Center for Digestive Disease, Beijing Digestive Disease Center, Beijing Key Laboratory for Precancerous Lesion of Digestive Disease, Beijing 100050, P.R. China
| | - Junchao Gu
- Beijing Tropical Medicine Research Institute, Beijing Friendship Hospital, Capital Medical University, Beijing 100050, P.R. China
| | - Shutian Zhang
- Department of Gastroenterology, Beijing Friendship Hospital, Capital Medical University, National Clinical Research Center for Digestive Disease, Beijing Digestive Disease Center, Beijing Key Laboratory for Precancerous Lesion of Digestive Disease, Beijing 100050, P.R. China
| |
Collapse
|
5
|
Nozu T, Miyagishi S, Nozu R, Takakusaki K, Okumura T. Repeated water avoidance stress induces visceral hypersensitivity: Role of interleukin-1, interleukin-6, and peripheral corticotropin-releasing factor. J Gastroenterol Hepatol 2017; 32:1958-1965. [PMID: 28299830 DOI: 10.1111/jgh.13787] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2016] [Revised: 03/03/2017] [Accepted: 03/13/2017] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND AIM Repeated water avoidance stress (WAS) induces visceral hypersensitivity. Additionally, it is also known to activate corticotropin-releasing factor (CRF), mast cells, and pro-inflammatory cytokines systems, but their precise roles on visceral sensation have not been determined definitely. The aim of the study was to explore this issue. METHODS Abdominal muscle contractions induced by colonic balloon distention, that is, visceromotor response (VMR) was detected electrophysiologically in conscious rats. WAS or sham stress as control for 1 h daily was loaded, and the threshold of VMR was determined before and at 24 h after the stress. RESULTS Repeated WAS for three consecutive days reduced the threshold of VMR, but sham stress did not induce any change. Astressin, a CRF receptor antagonist (50 μg/kg) intraperitoneally (ip) at 10 min before each WAS session, prevented the visceral allodynia, but the antagonist (200 μg/kg) ip at 30 min and 15 h before measurement of the threshold after completing 3-day stress session did not modify the response. Ketotifen, a mast cell stabilizer (3 mg/kg), anakinra, an interleukin (IL)-1 receptor antagonist (20 mg/kg) or IL-6 antibody (16.6 μg/kg) ip for two times before the measurement abolished the response. CONCLUSIONS Repeated WAS for three consecutive days induced visceral allodynia, which was mediated through mast cells, IL-1, and IL-6 pathways. Inhibition of peripheral CRF signaling prevented but did not reverse this response, suggesting that peripheral CRF may be an essential trigger but may not contribute to the maintenance of repeated WAS-induced visceral allodynia.
Collapse
Affiliation(s)
- Tsukasa Nozu
- Department of Regional Medicine and Education, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Saori Miyagishi
- Division of Gastroenterology and Hematology/Oncology, Department of Medicine, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Rintaro Nozu
- Department of Regional Medicine and Education, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Kaoru Takakusaki
- Research Center for Brain Function and Medical Engineering, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| | - Toshikatsu Okumura
- Division of Gastroenterology and Hematology/Oncology, Department of Medicine, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
| |
Collapse
|
6
|
Asano T, Tanaka KI, Tada A, Shimamura H, Tanaka R, Maruoka H, Mizushima T, Takenaga M. Ameliorative effect of chlorpromazine hydrochloride on visceral hypersensitivity in rats: possible involvement of 5-HT 2A receptor. Br J Pharmacol 2017; 174:3370-3381. [PMID: 28750135 DOI: 10.1111/bph.13960] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Revised: 07/13/2017] [Accepted: 07/17/2017] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND AND PURPOSE Visceral hypersensitivity is responsible for pathogenesis of irritable bowel syndrome (IBS). Therefore, its prevention can help avoid abdominal pain and discomfort in IBS. To find candidate drugs for visceral hypersensitivity, we screened existing medicines for their ability to prevent visceral sensitivity induced by colorectal distension (CRD) in rats and identified chlorpromazine, a typical antipsychotic drug, as a candidate compound. In this study, we investigated the effect of chlorpromazine on visceral hypersensitivity. EXPERIMENTAL APPROACH Visceral sensitivity (visceromotor response) was monitored by measuring the electrical activity of the abdominal external oblique muscle contraction in response to CRD using a barostat apparatus. Visceral hypersensitivity was induced by a colonic instillation of sodium butyrate or acetic acid in neonates. KEY RESULTS Oral administration of chlorpromazine suppressed butyrate-induced visceral hypersensitivity to CRD. Interestingly, atypical antipsychotic drugs, quetiapine and risperidone, ameliorated butyrate-induced visceral hypersensitivity, whereas the typical antipsychotic drugs, haloperidol and sulpiride, did not. Pharmacological analysis using specific inhibitors showed that a selective 5-HT2A receptor antagonist, ketanserin, suppressed butyrate-induced visceral hypersensitivity, whereas a selective dopamine D2 receptor antagonist, L-741626, did not. Furthermore, the 5-HT2A receptor agonist AL-34662 stimulated visceral sensitivity to CRD in healthy control rats but not in butyrate-treated rats. These findings suggest that increased 5-HT levels in the colon contribute to the induction of visceral hypersensitivity. CONCLUSIONS AND IMPLICATIONS Our results indicate that chlorpromazine ameliorates visceral hypersensitivity and that the 5-HT2A receptor is a potential therapeutic target for treating abdominal pain and discomfort in IBS.
Collapse
Affiliation(s)
- Teita Asano
- Institute of Medical Science, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Ken-Ichiro Tanaka
- Department of Pharmaceutical Sciences, Musashino University, Tokyo, Japan
| | - Arisa Tada
- Faculty of Pharmacy, Keio University, Tokyo, Japan
| | | | | | | | | | - Mitsuko Takenaga
- Institute of Medical Science, St. Marianna University School of Medicine, Kawasaki, Japan
| |
Collapse
|
7
|
Abstract
This paper is the thirty-eighth consecutive installment of the annual review of research concerning the endogenous opioid system. It summarizes papers published during 2015 that studied the behavioral effects of molecular, pharmacological and genetic manipulation of opioid peptides, opioid receptors, opioid agonists and opioid antagonists. The particular topics that continue to be covered include the molecular-biochemical effects and neurochemical localization studies of endogenous opioids and their receptors related to behavior, and the roles of these opioid peptides and receptors in pain and analgesia, stress and social status, tolerance and dependence, learning and memory, eating and drinking, drug abuse and alcohol, sexual activity and hormones, pregnancy, development and endocrinology, mental illness and mood, seizures and neurologic disorders, electrical-related activity and neurophysiology, general activity and locomotion, gastrointestinal, renal and hepatic functions, cardiovascular responses, respiration and thermoregulation, and immunological responses.
Collapse
Affiliation(s)
- Richard J Bodnar
- Department of Psychology and Neuropsychology Doctoral Sub-Program, Queens College, City University of New York, Flushing, NY 11367, United States.
| |
Collapse
|
8
|
Nozu T, Miyagishi S, Nozu R, Takakusaki K, Okumura T. Lipopolysaccharide induces visceral hypersensitivity: role of interleukin-1, interleukin-6, and peripheral corticotropin-releasing factor in rats. J Gastroenterol 2017; 52:72-80. [PMID: 27075754 DOI: 10.1007/s00535-016-1208-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2016] [Accepted: 03/24/2016] [Indexed: 02/04/2023]
Abstract
BACKGROUND Lipopolysaccharide (LPS) induces visceral hypersensitivity, and corticotropin-releasing factor (CRF) also modulates visceral sensation. Besides, LPS increases CRF immunoreactivity in rat colon, which raises the possibility of the existence of a link between LPS and the CRF system in modulating visceral sensation. The present study tried to clarify this possibility. METHODS Visceral sensation was assessed by abdominal muscle contractions induced by colonic balloon distention, i.e., visceromotor response, electrophysiologically in conscious rats. The threshold of visceromotor response was measured before and after administration of drugs. RESULTS LPS at a dose of 1 mg/kg subcutaneously (sc) decreased the threshold at 3 h after the administration. Intraperitoneal (ip) administration of anakinra (20 mg/kg), an interleukin-1 (IL-1) receptor antagonist, or interleukin-6 (IL-6) antibody (16.6 µg/kg) blocked this effect. Additionally, IL-1β (10 µg/kg, sc) or IL-6 (10 µg/kg, sc) induced visceral allodynia. Astressin (200 µg/kg, ip), a non-selective CRF receptor antagonist, abolished the effect of LPS, but astressin2-B (200 µg/kg, ip), a CRF receptor type 2 (CRF2) antagonist, did not alter it. Peripheral CRF receptor type 1 (CRF1) stimulation by cortagine (60 µg/kg, ip) exaggerated the effect of LPS, but activation of CRF2 by urocortin 2 (60 µg/kg, ip) abolished it. CONCLUSIONS LPS induced visceral allodynia possibly through stimulating IL-1 and IL-6 release. In addition, this effect was mediated through peripheral CRF signaling. Since the LPS-cytokine system is thought to contribute to altered visceral sensation in the patients with irritable bowel syndrome, these results may further suggest that CRF plays a crucial role in the pathophysiology of this disease.
Collapse
Affiliation(s)
- Tsukasa Nozu
- Department of Regional Medicine and Education, Asahikawa Medical University, Midorigaoka Higashi 2-1-1-1, Asahikawa, 078-8510, Japan.
| | - Saori Miyagishi
- Department of General Medicine, Asahikawa Medical University, Midorigaoka Higashi 2-1-1-1, Asahikawa, 078-8510, Japan
| | - Rintaro Nozu
- Department of Regional Medicine and Education, Asahikawa Medical University, Midorigaoka Higashi 2-1-1-1, Asahikawa, 078-8510, Japan
| | - Kaoru Takakusaki
- Research Center for Brain Function and Medical Engineering, Asahikawa Medical University, Midorigaoka Higashi 2-1-1-1, Asahikawa, 078-8510, Japan
| | - Toshikatsu Okumura
- Department of General Medicine, Asahikawa Medical University, Midorigaoka Higashi 2-1-1-1, Asahikawa, 078-8510, Japan
| |
Collapse
|