Mucosal Nerve Research Articles

Neuroepithelial circuit formed by innervation of sensory enteroendocrine cells.

Satiety and other core physiological functions are modulated by sensory signals arising from the surface of the gut. Luminal nutrients and bacteria stimulate epithelial biosensors called enteroendocrine cells. Despite being electrically excitable, enteroendocrine cells are generally thought to communicate indirectly with nerves through hormone secretion and not through direct cell-nerve contact. However, we recently uncovered in intestinal enteroendocrine cells a cytoplasmic process that we named neuropod. Here, we determined that neuropods provide a direct connection between enteroendocrine cells and neurons innervating the small intestine and colon. Using cell-specific transgenic mice to study neural circuits, we found that enteroendocrine cells have the necessary elements for neurotransmission, including expression of genes that encode pre-, post-, and transsynaptic proteins. This neuroepithelial circuit was reconstituted in vitro by coculturing single enteroendocrine cells with sensory neurons. We used a monosynaptic rabies virus to define the circuit's functional connectivity in vivo and determined that delivery of this neurotropic virus into the colon lumen resulted in the infection of mucosal nerves through enteroendocrine cells. This neuroepithelial circuit can serve as both a sensory conduit for food and gut microbes to interact with the nervous system and a portal for viruses to enter the enteric and central nervous systems.

TRPM8 on mucosal sensory nerves regulates colitogenic responses by innate immune cells via CGRP.

TRPM8 is the molecular sensor for cold; however, the physiological role of TRPM8+ neurons at mucosal surfaces is unclear. Here we evaluated the distribution and peptidergic properties of TRPM8+ fibers in naïve and inflamed colons, as well as their role in mucosal inflammation. We found that Trpm8−/− mice were hypersusceptible to DSS-induced colitis, and that Trpm8−/− CD11c+ DCs showed hyperinflammatory responses to TLR stimulation. This was phenocopied in CGRP receptor deficient, but not in substance P receptor deficient mice, suggesting a functional link between TRPM8 and CGRP. The DSS phenotype of CGRP receptor deficient mice could be adoptively transferred to WT mice, suggesting that CGRP suppresses the colitogenic activity of bone marrow-derived cells. TRPM8+ mucosal fibers expressed CGRP in human and mouse colon. Furthermore, neuronal CGRP contents were increased in colons from naïve and DSS treated Trpm8−/− mice, suggesting deficient CGRP release in the absence of TRPM8 triggering. Finally, treatment of Trpm8−/− mice with CGRP reversed their hyperinflammatory phenotype. These results suggest that TRPM8 signaling in mucosal sensory neurons is indispensable for the regulation of innate inflammatory responses via the neuropeptide CGRP.

Brain-derived neurotrophic factor accelerates gut motility in slow-transit constipation.

Brain-derived neurotrophic factor (BDNF) may play a critical role in gut motility. We aimed to investigate BDNF's physiologic effects on gut motility in slow-transit constipation (STC) and to explore the underlying molecular mechanisms. BDNF expression and alterations of colonic nerve fibre density in STC patients were first investigated. BDNF's effects on gastrointestinal motility of both BDNF(+/-) mice and loperamide-induced constipation mice were then examined in vivo and in vitro. Smooth muscle α-actin (α-SMA) expression, and nerve fibre, neuromuscular junction (NMJ) and smooth muscle cell (SMC) alterations were investigated. Finally, the effects of BDNF-induced TrkB-phospholipase C/inositol trisphosphate (TrkB-PLC/IP3) pathway activation on gut motility were investigated. In STC patients, BDNF expression and nerve fibre density were decreased, and mucosal nerve fibre ultrastructural degenerations were demonstrated. Gut motility was decreased in vivo and in vitro in BDNF(+/-) and constipation mice, with BDNF dose-dependently increasing gut motility. In BDNF(+/-) mice, α-SMA expression and nerve fibre density were decreased, and nerve fibre, NMJ and SMC ultrastructural degenerations were observed. Finally, TrkB-PLC/IP3 pathway antagonists dramatically attenuated BDNF's excitatory effect on gut motility, and exogenous BDNF induced an obvious increase in IP3 expression. BDNF plays an important regulatory role in gut motility in STC. It was mediated by altering the intestinal innervation structure, as well as smooth muscle secondary degeneration through a mechanism involving TrkB-PLC/IP3 pathway activation.

Intraepithelial lymphocyte eotaxin-2 expression and perineural mast cell degranulation differentiate allergic/eosinophilic colitis from classic IBD.

Allergic colitis shows overlap with classic inflammatory bowel disease (IBD). Clinically, allergic colitis is associated with dysmotility and abdominal pain, and mucosal eosinophilia is characteristic. We thus aimed to characterise mucosal changes in children with allergic colitis compared with normal tissue and classic IBD, focusing on potential interaction between eosinophils and mast cells with enteric neurones. A total of 15 children with allergic colitis, 10 with Crohn disease (CD), 10 with ulcerative colitis (UC), and 10 histologically normal controls were studied. Mucosal biopsies were stained for CD3 T cells, Ki-67, eotaxin-1, and eotaxin-2. Eotaxin-2, IgE, and tryptase were localised compared with mucosal nerves, using neuronal markers neurofilament protein, neuron-specific enolase, and nerve growth factor receptor. Overall inflammation was greater in patients with CD and UC than in patients with allergic colitis. CD3 T-cell density was increased in patients with allergic colitis, similar to that in patients with CD but lower than in patients with UC, whereas eosinophil density was higher than in all other groups. Eotaxin-1 and -2 were localised to basolateral crypt epithelium in all specimens, with eotaxin-1+ lamina propria cells found in all of the colitis groups. Eotaxin-2+ intraepithelial lymphocyte (IEL) density was significantly higher in allergic colitis specimens than in all other groups. Mast cell degranulation was strikingly increased in patients with allergic colitis (12/15) compared with that in patients with UC (1/10) and CD (0/1). Tryptase and IgE colocalised on enteric neurons in patients with allergic colitis but rarely in patients with IBD. Eotaxin-2+ IELs may contribute to the periepithelial eosinophil accumulation characteristic of allergic colitis. The colocalisation of IgE and tryptase with mucosal enteric nerves is likely to promote the dysmotility and visceral hyperalgesia classically seen in allergic gastrointestinal inflammation.

OC-067 Enhanced Perception Of Proximal Gastro-oesophageal Reflux: Impaired Mucosal Integrity Or Distinct Sensory Innervation?

IntroductionIn patients with GORD, including refractory disease, reflux events reaching the proximal oesophagus are more likely to be perceived than those only reaching the distal oesophagus. There is also experimental...

Tu1745 The TRPM8 Ion Channel Is Expressed in Colonic Mucosal Peptidergic Nerve Fibres, Which Increase During Inflammation and Associate With Dendritic Cells

G A A b st ra ct s in inflamed colons compared to WT + 2% DSS mice suggesting greater degree of vasculogenesis under inflammatory conditions. Conclusion: These results show that lymphatic dysregulation through genetic ablation of FOXC2 significantly exacerbates the onset, progression and severity of experimental IBD. These data suggest that alterations in lymphatic patterning and valve formation (under FOXC2 control) may contribute to IBD progression. Although abnormal lymphatic patterning is not clearly linked with IBD development, therapies which preserve postnatal valve integrity may help to resist gut injury or recover gut integrity in IBD associated gut injury. With lymphatics playing such an important potential role in the pathophysiology of IBD, research focusing on factors interfering with lymphatic damage and therapy to restore lymphatic functioning may open new doors for treatment modalities targeting this area. This work supported by Department of Defense Grant ‘Lymphatic Vascular Based Therapy in IBD' (W81XWH-11-1-0577)

414 Reversal of Opioid-Induced Constipation by Lubiprostone (Amitiza®) in Guinea Pig Ileum

Background & Aims: Brain-derived neurotrophic factor (BDNF) may play a critical role in gut motility. We aimed to investigate BDNF's physiologic effects on gut motility in slowtransit constipation (STC) and to explore the underlying molecular mechanisms. Methods: BDNF expression and alterations of colonic nerve fiber density in STC patients were first investigated. BDNF's effects on gastrointestinal motility of both BDNF+/− mice and loperamide-induced constipation mice were then examined in vivo and in vitro. Smooth muscle α-actin (α-SMA) expression, and nerve fiber, neuromuscular junction (NMJ), and smooth muscle cell (SMC) alterations were investigated. Finally, the effects of BDNF-induced TrkBphospholipase C/inositol trisphosphate (TrkB-PLC/IP3) pathway activation on gut motility were investigated. Results: In STC patients, BDNF expression and nerve fiber density were decreased, and mucosal nerve fiber ultrastructural degenerations were demonstrated. Gut motility was decreased in vivo and in vitro in BDNF+/− and constipation mice, with BDNF dose-dependently increasing gut motility. In BDNF+/− mice, α-SMA expression and nerve fiber density were decreased, and nerve fiber, NMJ, and SMC ultrastructural degenerations were observed. Finally, TrkB-PLC/IP3 pathway agonists dramatically attenuated BDNF's excitatory effect on gut motility, and exogenous BDNF induced an obvious increase in IP3 expression. Conclusions: BDNF plays an important regulatory role in gut motility in STC. It was mediated by altering the intestinal innervation structure, as well as smooth muscle secondary degeneration through a mechanism involving TrkB-PLC/IP3 pathway activation.

413 Brain-Derived Neurotrophic Factor Accelerates Gut Motility in Slow-Transit Constipation

Background & Aims: Brain-derived neurotrophic factor (BDNF) may play a critical role in gut motility. We aimed to investigate BDNF's physiologic effects on gut motility in slowtransit constipation (STC) and to explore the underlying molecular mechanisms. Methods: BDNF expression and alterations of colonic nerve fiber density in STC patients were first investigated. BDNF's effects on gastrointestinal motility of both BDNF+/− mice and loperamide-induced constipation mice were then examined in vivo and in vitro. Smooth muscle α-actin (α-SMA) expression, and nerve fiber, neuromuscular junction (NMJ), and smooth muscle cell (SMC) alterations were investigated. Finally, the effects of BDNF-induced TrkBphospholipase C/inositol trisphosphate (TrkB-PLC/IP3) pathway activation on gut motility were investigated. Results: In STC patients, BDNF expression and nerve fiber density were decreased, and mucosal nerve fiber ultrastructural degenerations were demonstrated. Gut motility was decreased in vivo and in vitro in BDNF+/− and constipation mice, with BDNF dose-dependently increasing gut motility. In BDNF+/− mice, α-SMA expression and nerve fiber density were decreased, and nerve fiber, NMJ, and SMC ultrastructural degenerations were observed. Finally, TrkB-PLC/IP3 pathway agonists dramatically attenuated BDNF's excitatory effect on gut motility, and exogenous BDNF induced an obvious increase in IP3 expression. Conclusions: BDNF plays an important regulatory role in gut motility in STC. It was mediated by altering the intestinal innervation structure, as well as smooth muscle secondary degeneration through a mechanism involving TrkB-PLC/IP3 pathway activation.

Capsaicin as an anti-obesity drug.

Laboratory studies support a role of capsaicin as an anti-obesity agent. Intestinal mucosal afferent nerves appear to play a role in controlling adipose tissue distribution between visceral and subcutaneous sites. Activation of the transient receptor potential vanilloid-1 channels by capsaicin prevents adipogenesis. A neurogenic mechanism modulates the regulation of fat metabolism by transient receptor potential vanilloid-1-sensitive sensory nerves. A neural pathway enables the selective activation of the central network that regulates brown adipose tissue sympathetic nerve activity in response to a specific stimulation of gastrointestinal transient receptor potential channels. Dietary capsaicin reduces metabolic dysregulation in obese/diabetic mice by enhancing expression of adiponectin and its receptor. The effects of capsaicin in adipose tissue and liver are related to its dual action on peroxisome proliferator-activated receptor alpha and transient receptor potential vanilloid-1 expression/activation. Local desensitization of the abdominal capsaicin-sensitive fibers attenuates the hypometabolic adaptation to food deprivation. Truncal vagotomy leads to significant reductions in both diet-induced weight gain and visceral abdominal fat deposition. Vagal de-afferentation leads to a more modest, but clinically and statistically significant, reduction in visceral abdominal fat. Thermogenesis and lipid metabolism-related proteins are altered upon capsaicin treatment in white adipose tissue. Capsaicin induces apoptosis and inhibits adipogenesis in preadipocytes and adipocytes. Epidemiologic data show that consumption of foods containing capsaicin is associated with a lower prevalence of obesity. Clinical evidence supports a role of capsaicin as an anti-obesity agent. Both oral and gastrointestinal exposure to capsaicin increase satiety and reduce energy and fat intake; the stronger reduction with oral exposure suggests a sensory effect of capsaicin. Bioactive components containing capsaicin may support weight maintenance after a hypocaloric diet. Capsaicin consumption 1 h before low intensity exercise is a valuable supplement for the treatment of individuals with hyperlipidemia and/or obesity because it improves lipolysis. Capsinoid ingestion increases energy expenditure through the activation of brown adipose tissue in humans. Capsinoid ingestion is associated with an increase in fat oxidation that is nearly significant; and two common genetic variants may be predictors of response. Further clinical research to develop convenient approaches for obese individuals to take advantage of this common dietary ingredient to prevent the onset or curtail the progression of obesity will be instructive and clinically relevant.

CGRP, a neurotransmitter of enteric sensory neurons, contributes to the development of food allergy due to the augmentation of microtubule reorganization in mucosal mast cells.

Neuro-immune interaction in the gut is substantially involved in the maintenance of intestinal immune homeostasis and the pathology of intestinal immune diseases. We have previously demonstrated that mucosal mast cells and nerve fibers containing CGRP, a neurotransmitter of intrinsic enteric sensory neurons, are markedly increased and exist in close proximity to each other in the colon of food allergy (FA) mice. In the present study, a CGRP-receptor antagonist BIBN4096BS significantly alleviated allergic symptoms in the murine FA model. In addition, the elevated numbers of mucosal mast cells in the proximal colon of FA mice were significantly decreased in that of BIBN4096BS-treated FA mice. Thus, we investigated the effects of CGRP on calcium-independent process in degranulation of mucosal mast cells since CGRP increases intracellular cAMP levels, but not Ca(2+) concentration. CGRP did not alter a calcium ionophore A23187-increased cytosolic Ca(2+) concentration in mucosal-type bone marrow-derived mast cells (mBMMCs), but did augment microtubule reorganization in resting and A23187-activated mBMMCs. Furthermore, CGRP alone failed to cause the degranulation of mBMMCs, but CGRP significantly enhanced the degranulation of mBMMCs induced by A23187. Together, these data indicate that CGRP- enhanced microtubule reorganization augments IgE-independent/non-antigenic stimuli-induced mucosal mast cell degranulation, thereby contributing to the development of FA.

Calretinin-Immunoreactive Mucosal Innervation in Very Short-Segment Hirschsprung Disease: A Potentially Misleading Observation

Absent calretinin-immunoreactive (CRir) mucosal innervation in aganglionic rectal biopsies is considered a useful diagnostic finding for Hirschsprung disease. Analysis of a series of rectosigmoid resections from patients with short-segment (>2-cm aganglionic, n = 9) and very short-segment (≤2-cm aganglionic, n = 9) Hirschsprung disease demonstrates that CRir mucosal nerves extend into the proximal 1-2 cm of aganglionic bowel, where their presence in distal rectal biopsies could complicate diagnosis of very short-segment disease. Indeed, retrospective analysis of preoperative, aganglionic, distal rectal biopsies from 4 of 9 patients with very short-segment Hirschsprung disease revealed CRir mucosal innervation. Accurate diagnosis was possible based on generous histopathological submucosal sampling to exclude ganglion cells and the presence of abundant large-caliber submucosal nerves (more than 4 nerves >30 µm thick/×200 field or more than 2 nerves >40 µm thick/×200 field). Absent CRir mucosal innervation supports the diagnosis of Hirschsprung disease, but the presence of CRir mucosal nerves does not exclude aganglionosis, especially in distal rectal biopsies from patients with very short-segment Hirschsprung disease.

Accumulation of α-synuclein in the bowel of patients in the pre-clinical phase of Parkinson’s disease

Parkinson's disease primarily affects the central nervous system, but autopsy and small patient studies have revealed autonomic nervous system pathology in most cases. We looked for α-synuclein pathology in routinely acquired biopsies from patients and matched controls. Immunocytochemistry was performed and assessed blind to the clinical diagnoses. One hundred and seventeen gastrointestinal tissue samples from 62 patients, and 161 samples from 161 controls, were examined. Twelve biopsies from seven patients showed accumulation of α-synuclein within mucosal and submucosal nerve fibres, and ganglia, which was more extensive with an antibody to phosphorylated, than with an antibody to non-phosphorylated, α-synuclein. These included gastric, duodenal and colonic biopsies, and were taken up to 8years prior to the onset of motor symptoms. All patients with positive biopsies had early autonomic symptoms and all controls were negative. This large scale study demonstrates that accumulation of α-synuclein in the gastrointestinal tract is a highly specific finding that could be used to confirm a clinical diagnosis of Parkinson's disease. We have shown that α-synuclein accumulation occurs prior to the onset of motor symptoms in the upper, as well as the lower gastrointestinal tract, remains present in serial biopsies until the onset of motor symptoms and is predominantly composed of phosphorylated α-synuclein. Accumulation of α-synuclein in the bowel therefore offers an accessible biomarker which allows further study of the early stages of the disease and could be of value in the assessment of disease modifying treatments.

New Roles of Serotonin and Tachykinins in Intestinal Mucositis?

The paper by Matsumoto et al. [1] published in this issue of Digestive Diseases and Sciences reports an investigation of expression of 5-hydroxytrypamine (5HT) and tachykinins and their cognate receptors in an experimental model of mucositis of the mouse jejunum induced by the chemotherapeutic agent 5-fluorouracil (5-FU). Mucositis is a serious adverse effect of common chemotherapeutic treatments. Damage to mucosa, prominent in the oral cavity (oral mucositis), also occurs in the esophagus, stomach, and small and large intestines (gastrointestinal mucositis). Gastrointestinal symptoms include pain, nausea and vomiting, ulceration, diarrhea, and rectal bleeding. Patients with mucositis often have to temporarily withdraw from chemotherapy, which can contribute to reduced cancer survival [2]. Current guidelines for treatment of gastrointestinal mucositis include use of the oral histamine H2-receptor antagonist ranitidine or a proton pump inhibitor to reduce gastric injury. Loperamide is recommended for control of diarrhea; if loperamide fails, subcutaneous octreotide is also recommended [3]. Mucosal damage was originally believed to result primarily from inhibition of epithelial cell proliferation, which reduces protection and repair of the mucosa. More recent evidence shows that chemotherapeutic agents stimulate nuclear factor-jB production; subsequent production of proinflammatory cytokines significantly induces mucositis [4]. Therapy limiting intestinal mucosal damage is not in common use, primarily because suitable molecular targets have not been identified. The publication by Matsumoto et al. builds on their previous findings that 5HT3 receptor antagonists reduce damage to mucosa, mucosal cytokine production, and enterocyte apoptosis caused by 5-FU in mice [5]. Their latest paper reports that 5HT3 and neurokinin (NK) NK1 receptor expression were upregulated, mostly in lamina propria macrophage-like cells (CD11?) of the jejunum, of mice injected intraperitoneally with 5-FU for 5 days, investigated on the 5th day. The study also reports increased 5HT and tachykinin (substance P) content of small intestine homogenate, although the number of cells expressing these compounds was unchanged. The number of mucosal 5HT3 receptor immunoreactive nerve fibers also increased. An important unanswered question is whether the results are clinically relevant, given that numerous studies have reported that 5HT3 receptors help modulate the immune– inflammatory axis. Rodents have only two genes encoding 5HT3 subunits whereas the human genome contains five 5-HT3 receptor-encoding genes, although the 5HT3C, 5HT3D, and 5HT3E subunits only express functional channels when co-expressed with 5HT3A [6]. It is currently unclear whether any of the 5HT3 receptor subtypes are expressed on human macrophages. 5HT2B and 5HT7 were the only serotonin receptor-encoding genes expressed above background levels in human macrophages produced by treatment of peripheral monocytes with GM-CSF or M-CSF (granulocyte macrophage and macrophage colonystimulating factors) [7]. Kapellar et al. [6] detected immunoreactivity to 5HT3A, 5HT3C, 5HT3D, and 5HT3E in lamina propria immune cells in the human colon, although their identity was not verified. There is, however, good evidence that 5HT3 receptors are expressed on human B. Callaghan J. B. Furness (&) Department of Anatomy and Neuroscience, University of Melbourne, Parkville, VIC, Australia e-mail: j.furness@unimelb.edu.au

Pituitary adenylate cyclase activating peptide-27 – like immunoreactive nerve fibers in the mucosal layer of canine gastrointestinal tract in physiology and during inflammatory bowel disease

Abstract Changes in the density of mucosal pituitary adenylate cyclase activating peptide-27 -like immunoreactive (PACAP-27 - LI) nerve fibers within various parts of the canine gastrointestinal (GI) tract during inflammatory bowel disease (IBD) were investigated. The distribution of nerves were studied, using a single-labelling immunofluorescence technique, in the mucosal layer of canine stomach, duodenum, jejunum, and descending colon. Canine IBD caused an increase in the density of PACAP- 27-LI mucosal nerves in all studied parts of GI tract. The results suggest that PACAP in the nervous system may be involved in pathological processes during IBD.

Role of duodenal mucosal nerve endings in the acid‐induced duodenogastric sensorimotor reflex: Effect of benzocaine in healthy humans

Duodenal acid exposure induces a duodenogastric reflex resulting in gastric relaxation, inhibition of antral motility, and sensitization of the proximal stomach to distension. Duodenal hypersensitivity to acid has been identified as a potential pathogenic mechanism in functional dyspepsia. The nature and localization of the duodenal acid-sensitive receptors are still elusive. We hypothesize that acid directly activates superficial afferent nerve endings in the duodenal mucosa, triggering the duodenogastric reflex. In a double-blind, randomized, crossover study in 13 healthy volunteers, benzocaine, a local anesthetic, vs saline was perfused in the duodenum 15 min before duodenal acid perfusion. Gastric responses were monitored by a barostat. Stepwise isobaric gastric distensions were performed before and during acid perfusion. Symptoms were evaluated by visual analogue scales for six dyspeptic symptoms and an overall perception score. Benzocaine perfusion caused a relaxation of the stomach prior to duodenal acidification, indicating the existence of an excitatory duodenogastric tone. Pretreatment of the duodenum with benzocaine reduced the acid-induced gastric relaxation by 50% and abolished the inhibition of phasic motility of the proximal stomach. Finally, sensitization to distension was more pronounced in the benzocaine condition because of higher proximal gastric volumes. These findings support a model in which different neuronal subpopulations are responsible for the motor and sensory limb of the acid-sensitive duodenogastric reflex, making benzocaine an unsuitable drug to treat duodenal hypersensitivity to acid. These data provide more insight in the contribution of duodenal neuronal input to gastric physiology in the fasting state.

Effect of Granulocyte Colony-Stimulating Factor on the Peripheral Nerves in Streptozotocin-Induced Diabetic Rat

There are controversial reports about the effect of granulocyte colony-stimulating factor (G-CSF) in peripheral nerve protection. Therefore, the present study aimed to investigate the effect of G-CSF on peripheral nerves in streptozotocin (STZ) induced diabetic rats. After STZ or vehicle injection, rats were divided into five groups (n=6) as follows: normal+vehicle, normal+G-CSF (50 µg/kg for 5 days), diabetes mellitus (DM)+vehicle, DM+G-CSF (50 µg/kg for 5 days), and DM+G-CSF extension (50 µg/kg for 5 days and followed by two injections per week up to 24 weeks). Our results showed that the current perception threshold was not significantly different among experimental groups. G-CSF treatment inhibited the loss of cutaneous nerves and gastric mucosal small nerve fibers in morphometric comparison, but statistical significance was not observed. The present results demonstrated that G-CSF has no harmful but minimal beneficial effects with respect to peripheral nerve preservation in diabetic rats.

A Unique Case of Systemic Sarcoidosis Presenting as Pseudoachalasia with Involvement of the Gastric Cardia

Background: A 59-year-old African American male presented to the Gastroenterology Clinic with a nine month history of solid food dysphagia. Endoscopy revealed nodular erythematous tissue at the gastric cardia, biopsies showed noncaseating granulomas. Chest imaging demonstrated bilateral hilar lymphadenopathy, confirming the diagnosis of systemic sarcoidosis, and oral corticosteroid therapy was initiated. High-resolution manometry showed incomplete relaxation of the lower esophageal sphincter consistent with possible achalasia. Further evaluation with EUS showed paraesophageal lymphadenopathy causing extrinsic esophageal compression. The patient's dysphagia responded to serial esophageal dilations, however, he was referred to surgery for consideration for cardiomyotomy or lymphadenectomy as a definitive treatment. Discussion: Gastric involvement in patients with systemic sarcoidosis has been reported in 2.5% of cases. Although our patient developed granulomatous involvement of the gastric cardia, it is the gastric antrum that is most frequently affected. To our knowledge only one case of pseudoachalasia due to gastric cardia sarcoidosis has been previously reported, and was successfully treated with cardiomyotomy. Sarcoidosis has been implicated as a cause of pseudoachalasia in roughly 2-4% of symptomatic patients with a manometric pattern of primary achalasia. Previous reports have described dysphagia symptoms from mechanical compression by lymphadenopathy or granulomatous infiltration of the mucosal musculature and nerve fibers. Multiple cases of esophageal sarcoidosis have been reported in the literature; some of which responded to medical management with corticosteroid therapy, endoscopic dilations, or botulinum toxin injections. Definitive surgical interventions in the form of cardiomyotomy or lymphadenectomy will be pursued should the patient's symptoms become refractory to medical management. Conclusion: To our knowledge, our patient is the second reported case of pseudoachalasia secondary to gastric cardia sarcoidosis. Surgery has been suggested for patients with esophageal and gastric sarcoidosis in the form of cardiomyotomy or lymphadenectomy to patients refractory to medical management. Our patient, however, has responded to a combined medical and endoscopic approach.Figure: No Caption available.

Growth-Associated Protein 43 Expression in Ganglionic and Aganglionic Colon

Abstract Objectives: Because of its specificity for nerve fibers of the enteric nervous system, calretinin is an effective adjunctive marker in the assessment for Hirchsprung disease. Growth associated protein (GAP-43) has been shown to be expressed in nerve fibers within the intestinal lamina propria. No prior report compares GAP-43 expression in ganglionic versus aganglionic intestine. Methods: Six consecutive Hirschsprung endorectal pull through specimens were retrieved from our archives. In addition 3 controls were selected from colonic resections for reasons other than Hirschsprung Disease. Immunoperoxidase for GAP-43 was carried out on the ganglionic and aganglionic segments of all cases and controls. Submucosal ganglion soma positivity and nerve fiber positivity within the lamina propria were graded on a subjective scale of 1-3 that incorporated both strength and density. Data: GAP-43 strongly stained submucosal ganglion cells and nerve fibers within the lamina propria in 6/6 of the ganglionic segments and 3/3 of the normally innervated controls . GAP-43 did not show any ganglion cell body positivity within the aganglionic segments; however, all 6 aganglionic segment lamina propria were positive for nerve fiber staining. There was a small subjective increase in the amount of nerve fiber positivity for GAP-43 in ganglionic segments and controls versus aganglionic segments. Conclusion: GAP-43 marks mucosal nerve fibers in ganglionic intestine but also aganglionic intestine and thus is less useful than calretinin as a marker for Hirschsprung Disease. The abundant mucosal nerves highlighted by GAP-43 requires further characterization.

Growth-associated Protein-43 (GAP-43) Expression In Ganglionic and Aganglionic Colon.

Abstract Objectives: Because of its specificity for nerve fibers of the enteric nervous system, calretinin is an effective adjunctive marker in the assessment for Hirchsprung disease. Growth associated protein (GAP-43) has been shown to be expressed in nerve fibers within the intestinal lamina propria. No prior report compares GAP-43 expression in ganglionic versus aganglionic intestine. Methods: Six consecutive Hirschsprung endorectal pull through specimens were retrieved from our archives. In addition 3 controls were selected from colonic resections for reasons other than Hirschsprung Disease. Immunoperoxidase for GAP-43 was carried out on the ganglionic and aganglionic segments of all cases and controls. Submucosal ganglion soma positivity and nerve fiber positivity within the lamina propria were graded on a subjective scale of 1-3 that incorporated both strength and density. Data: GAP-43 strongly stained submucosal ganglion cells and nerve fibers within the lamina propria in 6/6 of the ganglionic segments and 3/3 of the normally innervated controls . GAP-43 did not show any ganglion cell body positivity within the aganglionic segments; however, all 6 aganglionic segment lamina propria were positive for nerve fiber staining. There was a small subjective increase in the amount of nerve fiber positivity for GAP-43 in ganglionic segments and controls versus aganglionic segments. Conclusion: GAP-43 marks mucosal nerve fibers in ganglionic intestine but also aganglionic intestine and thus is less useful than calretinin as a marker for Hirschsprung Disease. The abundant mucosal nerves highlighted by GAP-43 requires further characterization.

Selective survival of calretinin- and vasoactive-intestinal-peptide-containing nerve elements in human chagasic submucosa and mucosa

Chronic Chagas' disease is frequently characterized by massive myenteric neuron loss resulting in megacolon with severely and irreversibly disturbed motility. Here, we focused on two submucosal neuron populations, immunoreactive for calretinin (CALR) or somatostatin (SOM), and their respective mucosal nerve fibres in chagasic megacolon. Surgically removed megacolonic segments of seven chagasic patients were compared with seven age- and region-matched non-chagasic control segments. Evaluation included immunohistochemical triple-staining of cryosections for CALR, SOM and peripherin or for CALR and vasoactive intestinal peptide (VIP) and of submucosal whole-mounts for CALR, SOM and the pan-neuronal marker anti-HuC/D. Submucosal neuron counts in chagasic tissue revealed neuron numbers reduced to 51.2% of control values. In cryosections, nerve fibre area measurements revealed 8.6% nerve fibre per mucosal area in control segments, but this value decreased to 1.5% in megacolonic segments. In both evaluations, a disproportionate decrease of SOM-reactive nerve elements was observed. The proportions of SOM-positive neurons related to the total neuron number declined to 2% (control 10%) and the proportion of SOM-reactive mucosal nerve fibres related to the whole mucosal area to 0.014% (control 1.8%)in chagasic tissue. The second set of cryosections revealed extensive colocalization of CALR with VIP in both surviving submucosal perikarya and mucosal nerve fibres. We suggest that VIP, a neuroprotective and neuroeffectory peptide typically contained in submucosal neurons, allows both the VIP-containing neurons to endure and the patients to survive by maintaining their mucosal barrier, despite the almost complete loss of colonic motility for decades.