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Radhika Krishna OH, Aleem MA, Kayla G. Abnormalities of the intestinal pacemaker cells, enteric neurons, and smooth muscle in intestinal atresia. J Lab Physicians 2019; 11:180-185. [PMID: 31579250 PMCID: PMC6771318 DOI: 10.4103/jlp.jlp_94_18] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Accepted: 02/09/2019] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Small bowel atresia is a congenital disorder that carves a substantial morbidity. Numerous postoperative gastrointestinal motility problems occur. The underlying cause of this motility disorder is still unclear. Interstitial cells of Cajal (ICC) play a major role in gastrointestinal motility. AIMS AND OBJECTIVES To investigate the morphological changes of enteric nervous system and ICC in small bowel atresia. MATERIAL AND METHODS Resected small bowel specimen from affected patients (n=15) were divided into three parts (proximal, distal, atretic). Standard histology and immunohistochemistry with anti C-KIT receptor antibody (CD117), calretinin and α-SMA was carried out. The density of myenteric ICCs in the proximal, atretic and distal parts was demonstrated by CD 117 while Calretinin was used for ganglion cells and nerve bundles, α-SMA highlighted muscle hypertrophy. RESULT AND CONCLUSION The proximal and distal bowel revealed clear changes in the morphology and density of enteric nervous system and interstitial cells of Cajal..
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Affiliation(s)
- OH Radhika Krishna
- Department of Pathology, Niloufer Hospital for Women and Children, Hyderabad, Telangana, India
| | - Mohammed Abdul Aleem
- Department of Pathology, Niloufer Hospital for Women and Children, Hyderabad, Telangana, India
| | - Geetha Kayla
- Department of Pathology, Niloufer Hospital for Women and Children, Hyderabad, Telangana, India
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Abstract
The enteric nervous system is vulnerable to a range of congenital and acquired disorders that disrupt the function of its neurons or lead to their loss. The resulting enteric neuropathies are some of the most challenging clinical conditions to manage. Neural stem cells offer the prospect of a cure given their potential ability to replenish missing or dysfunctional neurons. This article discusses diseases that might be targets for stem cell therapies and the barriers that could limit treatment application. We explore various sources of stem cells and the proof of concept for their use. The critical steps that remain to be addressed before these therapies can be used in patients are also discussed. Key milestones include the harvesting of neural stem cells from the human gut and the latest in vivo transplantation studies in animals. The tremendous progress in the field has brought experimental studies exploring the potential of stem cell therapies for the management of enteric neuropathies to the cusp of clinical application.
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Affiliation(s)
- Alan J Burns
- Neural Development and Gastroenterology Units, Birth Defects Research Centre, UCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK
| | - Nikhil Thapar
- 1] Neural Development and Gastroenterology Units, Birth Defects Research Centre, UCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK. [2] Division of Neurogastroenterology and Motility, Department of Paediatric Gastroenterology, Great Ormond Street Hospital, Great Ormond Street, London WC1N 3JH, UK
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Hanani M, Grossman S, Nissan A, Eid A. Morphological and quantitative study of the myenteric plexus in the human tenia coli. Anat Rec (Hoboken) 2012; 295:1321-6. [PMID: 22678779 DOI: 10.1002/ar.22511] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Accepted: 02/29/2012] [Indexed: 12/15/2022]
Abstract
The longitudinal muscle in the large intestine in humans and some other mammalian species is concentrated in regions known as "tenia coli." The myenteric plexus under the tenia is believed to be highly developed to control the adjacent large muscle mass, however, data on the innervation of this region are very scarce. We used whole mount preparations of human colon to characterize the organization of the myenteric plexus under the tenia coli (UT) and compared it with the plexus between the tenia (BT). Using histochemical staining for NADPH diaphorase, we found that the meshwork UT was 50% denser than BT, and that the ganglia UT were 30% wider. The density and size of the NADPH-d positive neurons UT were similar to those of BT. We conclude that the myenteric plexus UT is considerably more developed than BT, and suggest to understand the control of colonic motility, the myenteric plexus UT needs to be further investigated.
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Affiliation(s)
- Menachem Hanani
- Laboratory of Experimental Surgery, Hadassah-Hebrew University Medical Center, Mount Scopus, Jerusalem 91240, Israel.
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Gfroerer S, Metzger R, Fiegel H, Ramachandran P, Rolle U. Differential changes in intrinsic innervation and interstitial cells of Cajal in small bowel atresia in newborns. World J Gastroenterol 2010; 16:5716-21. [PMID: 21128321 PMCID: PMC2997987 DOI: 10.3748/wjg.v16.i45.5716] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2010] [Revised: 04/19/2010] [Accepted: 04/26/2010] [Indexed: 02/06/2023] Open
Abstract
AIM To investigate morphological changes of the enteric nervous system (ENS) and the interstitial cells of Cajal (ICCs) in small bowel atresia. METHODS Resected small bowel specimens from affected patients (n = 7) were divided into three parts (proximal, atretic, distal). Standard histology and enzyme immunohistochemistry anti-S100, anti-protein gene product (PGP) 9.5, anti-neurofilament (NF), anti-c-kit-receptor (CD117) was carried out on conventional paraffin sections of the proximal and distal part. RESULTS The neuronal and glial markers (PGP 9.5, NF, S-100) were expressed in hypertrophied ganglia and nerve fibres within the myenteric and submucosal plexuses. Furthermore, the submucous plexus contained typical giant ganglia. The innervation pattern of the proximal bowel resembled intestinal neuronal dysplasia. The density of myenteric ICCs was clearly reduced in the proximal bowel, whereas a moderate number of muscular ICCs were found. The anti-CD117 immunoreaction revealed additional numerous mast cells. The distal bowel demonstrated normal morphology and density of the ENS, the ICCs and the mast cells. CONCLUSION The proximal and distal bowel in small bowel atresia revealed clear changes in morphology and density of the ENS and ICCs.
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de Vries P, Soret R, Suply E, Heloury Y, Neunlist M. Postnatal development of myenteric neurochemical phenotype and impact on neuromuscular transmission in the rat colon. Am J Physiol Gastrointest Liver Physiol 2010; 299:G539-47. [PMID: 20522637 DOI: 10.1152/ajpgi.00092.2010] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Profound changes in intestinal motility occur during the postnatal period, but the involvement of the enteric nervous system (ENS), a key regulator of gastrointestinal (GI) motility, in these modifications remains largely unknown. We therefore investigated the postnatal development of the ENS phenotype and determined its functional repercussion on the neuromuscular transmission in the rat colon. Sprague-Dawley rats were euthanized at postnatal day (P) 1, P3, P5, P7, P14, P21, and P36. Whole mounts of colonic myenteric plexus were stained with antibodies against choline acetyltransferase (ChAT), neuronal nitric oxide synthase (nNOS), and HuC/D. Colonic contractile response induced by electrical field stimulation (EFS) was investigated in organ chambers in absence or presence of N-nitro-l-arginine methyl ester (l-NAME) and/or atropine. In vivo motility was assessed by measurement of the colonic bead latency time. Randomly occurring ex vivo contractions appeared starting at P5. Starting at P14, rhythmic phasic contractions occurred whose frequency and amplitude increased over time. In vivo, bead latency was significantly reduced between P14 and P21. Ex vivo, EFS-induced contractile responses increased significantly over time and were significantly reduced by atropine starting at P14 but were sensitive to l-NAME only after P21. The proportion of ChAT-immunoreactive (IR) neurons increased time dependently starting at P14. The proportion of nNOS-IR neurons increased as early as P5 compared with P1 but did not change afterward. Our data support a key role for cholinergic myenteric pathways in the development of postnatal motility and further identify them as putative therapeutic target for the treatment of GI motility disorders in the newborn.
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Schäfer KH, Van Ginneken C, Copray S. Plasticity and neural stem cells in the enteric nervous system. Anat Rec (Hoboken) 2010; 292:1940-52. [PMID: 19943347 DOI: 10.1002/ar.21033] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The enteric nervous system (ENS) is a highly organized part of the autonomic nervous system, which innervates the whole gastrointestinal tract by several interconnected neuronal networks. The ENS changes during development and keeps throughout its lifespan a significant capacity to adapt to microenvironmental influences, be it in inflammatory bowel diseases or changing dietary habits. The presence of neural stem cells in the pre-, postnatal, and adult gut might be one of the prerequisites to adapt to changing conditions. During the last decade, the ENS has increasingly come into the focus of clinical neural stem cell research, forming a considerable pool of neural crest derived stem cells, which could be used for cell therapy of dysganglionosis, that is, diseases based on the deficient or insufficient colonization of the gut by neural crest derived stem cells; in addition, the ENS could be an easily accessible neural stem cell source for cell replacement therapies for neurodegenerative disorders or traumatic lesions of the central nervous system.
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Affiliation(s)
- Karl-Herbert Schäfer
- Department of Biotechnology, University of Applied Sciences Kaiserslautern, Amerikastrasse 1, Zweibrücken, Germany.
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Di Nardo G, Stanghellini V, Cucchiara S, Barbara G, Pasquinelli G, Santini D, Felicani C, Grazi G, Pinna AD, Cogliandro R, Cremon C, Gori A, Corinaldesi R, Sanders KM, De Giorgio R. Enteric neuropathology of congenital intestinal obstruction: A case report. World J Gastroenterol 2006; 12:5229-33. [PMID: 16937539 PMCID: PMC4088026 DOI: 10.3748/wjg.v12.i32.5229] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/07/2006] [Revised: 05/15/2006] [Accepted: 05/22/2006] [Indexed: 02/06/2023] Open
Abstract
Experimental evidence indicates that chronic mechanical sub-occlusion of the intestine may damage the enteric nervous system (ENS), although data in humans are lacking. We here describe the first case of enteric degenerative neuropathy related to a congenital obstruction of the gut. A 3-year and 9-mo old girl began to complain of vomiting, abdominal distension, constipation with air-fluid levels at plane abdominal radiology. Her subsequent medical history was characterized by 3 operations: the first showed dilated duodeno-jejunal loops in the absence of occlusive lesions; the second (2 years later) was performed to obtain full-thickness biopsies of the dilated intestinal loops and revealed hyperganglionosis at histopathology; the third (9 years after the hyperganglionosis was identified) disclosed a Ladd's band which was removed and the associated gut malrotation was corrected. Repeated intraoperative full-thickness biopsies showed enteric degenerative neuropathy along with reduced interstitial cells of Cajal network in dilated loops above the obstruction and a normal neuromuscular layer below the Ladd's band. One year after the latest surgery the patient tolerated oral feeding and did well, suggesting that congenital (partial) mechanical obstruction of the small bowel in humans can evoke progressive adaptive changes of the ENS which are similar to those found in animal models of intestinal mechanical occlusion. Such ENS changes mimic neuronal abnormalities observed in intestinal pseudo-obstruction.
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Affiliation(s)
- Giovanni Di Nardo
- Department of Pediatrics, Pediatric Gastroenterology Unit, University of Rome La Sapienza, Rome, Italy
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Huang TY, Hanani M. Morphological and electrophysiological changes in mouse dorsal root ganglia after partial colonic obstruction. Am J Physiol Gastrointest Liver Physiol 2005; 289:G670-8. [PMID: 15920014 DOI: 10.1152/ajpgi.00028.2005] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
There is evidence that sensitization of neurons in dorsal root ganglia (DRG) may contribute to pain induced by intestinal injury. We hypothesized that obstruction-induced pain is related to changes in DRG neurons and satellite glial cells (SGCs). In this study, partial colonic obstruction was induced by ligation. The neurons projecting to the colon were traced by an injection of 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate into the colon wall. The electrophysiological properties of DRG neurons were determined using intracellular electrodes. Dye coupling was examined with an intracellular injection of Lucifer yellow (LY). Morphological changes in the colon and DRG were examined. Pain was assessed with von Frey hairs. Partial colonic obstruction caused the following changes. First, coupling between SGCs enveloping different neurons increased 18-fold when LY was injected into SGCs near neurons projecting to the colon. Second, neurons were not coupled to other neurons or SGCs. Third, the firing threshold of neurons projecting to the colon decreased by more than 40% (P < 0.01), and the resting potential was more positive by 4-6 mV (P < 0.05). Finally, the number of neurons displaying spontaneous spikes increased eightfold, and the number of neurons with subthreshold voltage oscillations increased over threefold. These changes are consistent with augmented neuronal excitability. The pain threshold to abdominal stimulation decreased by 70.2%. Inflammatory responses were found in the colon wall. We conclude that obstruction increased neuronal excitability, which is likely to be a major factor in the pain behavior observed. The augmented dye coupling between glial cells may contribute to the neuronal hyperexcitability.
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Affiliation(s)
- Tian-Ying Huang
- Laboratory of Experiment Surgery, Hebrew University-Hadassah Medical School, Mount Scopus, Jerusalem 91240, Israel
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Diana A, Pietra M, Guglielmini C, Boari A, Bettini G, Cipone M. Ultrasonographic and pathologic features of intestinal smooth muscle hypertrophy in four cats. Vet Radiol Ultrasound 2003; 44:566-9. [PMID: 14599170 PMCID: PMC7169284 DOI: 10.1111/j.1740-8261.2003.tb00508.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The ultrasonographic findings for four cats with intestinal smooth muscle hypertrophy are described. In two cats, intestinal smooth muscle hypertrophy was associated with chronic enteritis. In the remaining two cats, intestinal smooth muscle hypertrophy affected the intestinal tract proximal to stenosis due to alimentary lymphoma and an intestinal foreign body, respectively. Moderate increased thickness of the affected intestinal wall, measuring 7-8 mm, was evident on abdominal ultrasonographic examination of all subjects. In addition, the ultrasonographic five-layered feature of the intestinal wall was maintained, and only the muscular layer appeared thickened. Abdominal ultrasound allowed a presumptive diagnosis of intestinal smooth muscle hypertrophy that was confirmed histologically in all cats.
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Affiliation(s)
- Alessia Diana
- Department of Veterinary Clinical Sciences, University of Bologna, Via Tolara di Sopra 50, 1-40064 Ozzano Emilia, BO, Italy
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Kapur RP. Neuronal dysplasia: A controversial pathological correlate of intestinal pseudo-obstruction. ACTA ACUST UNITED AC 2003; 122A:287-93. [PMID: 14518065 DOI: 10.1002/ajmg.a.20470] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
The infant or child with intestinal pseudo-obstruction poses many challenges for geneticists and other specialists. Although a well-defined anatomic diagnosis (e.g., Hirschsprung disease) can be established for a subset of patients, the pathological correlates for many patients are non-existent or controversial. Intestinal neuronal dysplasia (IND) is frequently considered in the differential diagnosis, despite the fact that existence and significance of the abnormal histopathological features that characterize IND are hotly debated. This review highlights some of the concerns regarding this diagnosis including problems with the diagnostic criteria, the manner in which these criteria are applied in contemporary pathology practices, and the likelihood that many of the pathological findings are secondary consequences of impaired motility with no other clear clinical significance. Possible genetic and developmental bases for IND are also discussed.
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Affiliation(s)
- Raj P Kapur
- Department of Laboratories, Children's Hospital and Regional Medical Center, University of Washington, Seattle, Washington 98105, USA.
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Phillips RJ, Kieffer EJ, Powley TL. Aging of the myenteric plexus: neuronal loss is specific to cholinergic neurons. Auton Neurosci 2003; 106:69-83. [PMID: 12878075 DOI: 10.1016/s1566-0702(03)00072-9] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Neuron loss occurs in the myenteric plexus of the aged rat. The myenteric plexus is composed of two mutually exclusive neuronal subpopulations expressing, respectively, nitrergic and cholinergic phenotypes. The goal of the present study, therefore, was to determine if neuron loss is specific to one phenotype, or occurs in both. Ad libitum fed virgin male Fischer 344 rats of 3 and 24 months of age were used in each of two neuronal staining protocols (n=10/age/neuron stain). The stomach, duodenum, jejunum, ileum, colon, and rectum were prepared as whole mounts and processed with either NADPHd or Cuprolinic Blue to stain, respectively, the nitrergic subpopulation or the entire population of myenteric neurons. Neuron numbers and sizes were determined for each preparation. Neuron counts from 24-month-old rats were corrected for changes in tissue area resulting from growth. There was no age-related loss of NADPHd-positive neurons for any of the regions sampled, whereas significant losses of Cuprolinic Blue-labeled neurons occurred in the small and large intestines of 24-month-old rats. At the two ages, the average neuron sizes were similar in the stomach and small intestine for both stains, but neurons in the large intestine were significantly larger at 24 months. In addition, numerous swollen NADPHd-positive axons were found in the large intestine at 24 months. These findings support the hypothesis that age-related cell loss in the small and large intestines occurs exclusively in the cholinergic subpopulation. It appears, however, from the somatic hypertrophy and the presence of swollen axons that the nitrergic neurons are not completely spared from the effects of age.
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Affiliation(s)
- Robert J Phillips
- Department of Psychological Sciences, Purdue University, 703 Third Street, West Lafayette, IN 47907-2004, USA.
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Phillips RJ, Baronowsky EA, Powley TL. Long-term regeneration of abdominal vagus: efferents fail while afferents succeed. J Comp Neurol 2003; 455:222-37. [PMID: 12454987 DOI: 10.1002/cne.10470] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Vagal afferents regenerate, by 18 weeks after subdiaphragmatic transection, to reinnervate the gut and to differentiate into the two types of terminals normally found in the smooth muscle wall of the gastrointestinal (GI) tract (Phillips et al. [2000] J Comp Neurol. 421:325-346). Regeneration, however, is neither complete nor entirely accurate by 18 weeks. Moreover, the capacity of the vagal efferents to reinnervate the GI tract under comparable conditions has not been evaluated. Therefore, to determine whether a more extended postaxotomy survival interval would (1). result in more extensive reinnervation of smooth muscle, (2). facilitate correction of the inaccuracies of the regenerated axons and terminals, and (3). yield motor as well as sensory reinnervation of GI targets, Sprague-Dawley rats received either complete subdiaphragmatic vagotomies (n = 18) or sham surgeries (n = 12). Physiological endpoints that might normalize as vagal elements regenerated, including body weight, daily food intake, size of first daily meal, and metabolic efficiency, were monitored. At 45 weeks after the vagotomies, the animals were randomly assigned to afferent (wheat germ agglutinin-horseradish peroxidase) or efferent (cholera toxin subunit B-horseradish peroxidase) mapping conditions, and labeled axons and terminals in the stomach and first 8 cm of the small intestine were inventoried in whole-mounts. Afferent regeneration was more extensive at 45 weeks than previously observed at 18 weeks after surgery; however, the amount of GI innervation was still not comparable to the intact pattern of the sham rats. Furthermore, abnormal patterns of sensory organization occurred throughout the reinnervated field, with small bundles of axons forming complex tangles and some individual axons terminating in ectopic locations. The presence of growth cone profiles suggested that vagal reorganization was ongoing even 45 weeks after surgery. In contrast to this relatively extensive, albeit incomplete, sensory reinnervation of the gut, motor fibers had failed to reinnervate the GI tract. Thus, dramatic differences exist in the regenerative capacities of the sensory and motor arms of the vagus under the same surgical and maintenance conditions. Furthermore, the functional measures of disordered energy regulation did not normalize over the 45 weeks during which afferent but not efferent innervation was restored.
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Affiliation(s)
- Robert J Phillips
- Purdue University, Department of Psychological Sciences, West Lafayette, Indiana 47907, USA.
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Kapur RP. Neuropathology of paediatric chronic intestinal pseudo-obstruction and related animal models. J Pathol 2001; 194:277-88. [PMID: 11439358 DOI: 10.1002/path.885] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chronic intestinal pseudo-obstruction (CIP) in paediatric patients is due to heterogeneous aetiologies that include primary disorders of the enteric nervous system. These conditions are poorly delineated by contemporary diagnostic approaches, in part because the complex nature of the enteric nervous system may shelter significant physiological defects behind subtle or quantitative anatomical changes. Until recently, relatively few experimental animal models existed for paediatric CIP. However, the availability of rodent models, particularly novel mutants created in the last few years by genetic manipulations, has brought unprecedented opportunities to investigate molecular, cellular, physiological, and histological details of enteric neuropathology. Information gleaned from studies of these animals is likely to change diagnostic and therapeutic approaches to paediatric CIP and related conditions.
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Affiliation(s)
- R P Kapur
- Department of Pathology, University of Washington, Seattle, Washington 98195, USA.
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Brehmer A, Frieser M, Graf M, Radespiel-Tröger M, Göbel D, Neuhuber W. Dendritic hypertrophy of Stach type VI neurons within experimentally altered ileum of pigs. Auton Neurosci 2001; 89:31-7. [PMID: 11474644 DOI: 10.1016/s1566-0702(01)00250-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Myenteric neurons were investigated morphometrically to answer the question if type-specific somal hypertrophy of type VI neurons in mechanically stressed ileum of pigs, which was known from an earlier study, is correlated with an increased dendritic arborization, that is, with dendritic hypertrophy. Muscular hypertrophy was induced in the ileum of two juvenile pigs by narrowing the gut circumference (mechanical stenosis) and by reversing a loop of ileum which results in an antiperistaltic segment (functional stenosis), respectively. After a survival time of 6 weeks, wholemounts from the pre- and poststenotic ileal regions, from the antiperistaltic segment as well as from an age matched control animal, were silver impregnated. Dendritic parameters of Stach types IV and VI neurons were recorded using a computer-aided morphometric program and analysed statistically. Type IV neurons showed no change of dendritic parameters, neither within control nor within stenosed ileal segments. In contrast, the type VI neurons displayed increased dendritic parameters within zones of muscular hypertrophy such as total dendritic length, numbers of dendrites, of dendritic branching points and of dendritic endings. We suggest that type VI neurons may participate as descending nitrergic interneurons or motorneurons in the control of muscular function, thus, undergoing plastic changes in case of experimental muscular hypertrophy. Type IV neurons which are involved in the regulation of mucosal processes were not affected by muscular hypertrophy.
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Affiliation(s)
- A Brehmer
- Institut für Anatomie I, Universität Erlangen-Nürnberg, Erlangen, Germany.
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