Morphoquantitative study of Rattus norvegicus submucosal plexus by different neuronal evidentiation histochemical techniques / Estudio morfocuantitativo del plexo submucoso de Rattus norvegicus por medio de diferentes técnicas histoquímicas para verificar características neuronales

Enteric nervous plexuses have been the object of several studies, specially the myenteric plexus whose studies describe its organization, functions and alterations. On the other hand, the submucosal plexus has been less studied and still needs descriptive studies. To analyze morphologically and quantitatively submucosal neurons of the jejunum of 90-day-old healthy rats using different techniques for neuronal staining as a way to provide normality data to compare with future experimental studies. Whole mount preparations of the jejunum were submitted to Giemsa, NADH-diaphorase and NADPH-diaphorase techniques to stain the total neuronal population, more metabolically active subpopulation and subpopulation of nitrergic neurons, respectively. Neurons of the submucosal plexus of adult rats are mainly organized in ganglia with varied sized and shapes. Giemsa technique stained 243.93 ± 7.68 neurons per mm2. Regarding the total population stained by Giemsa, NADH- diaphorase positive (139.09 ± 11.14/mm2) neurons represented 57 % and NADPH-diaphorase positive (18.17 ± 0.28/mm2) represented 7.5 %. The area of the cell body was bigger in nitrergic neurons (412.29 ± 150.22) than in the ones stained by Giemsa (254.71 ± 63.32) and NADH-diaphorase positive (243.98 ± 123.82).

El plexo nervioso entérico ha sido objeto de varios estudios, especialmente el plexo mientérico, cuyos estudios consisten en describir su organización, funciones y alteraciones. Por otro lado, el plexo submucoso ha sido menos investigado y todavía necesita estudios descriptivos. Para analizar morfológica y cuantitativamente las neuronas de la submucosa del yeyuno de ratas de 90 días de edad, se realizaron diferentes técnicas de tinción neuronales, en animales sanos, como una forma de proporcionar datos de normalidad y compararlo con futuros estudios experimentales. Se realizaron montajes con preparados enteros del yeyuno que fueron sometidos a las técnicas de Giemsa, de NADPH-diaforasa y NADH-diaforasa para teñir la población total neuronal, subpoblación más activa metabólicamente y subpoblación de neuronas nitrérgicas, respectivamente. Las neuronas del plexo submucoso de ratas adultas se organizan principalmente en los ganglios con variaciones de tamaño y formas. Con la técnica de Giemsa se tiñeron 243.93±7.68 neuronas por mm2. Con respecto a la población total teñida con Giemsa, fueron positivas para NADH- diaforasa en 139.09 ±11.14 / mm2 neuronas, representando el 57% y fueron positivas para NADPH-diaforasa en 18,17 ± 0,28 / mm2 neuronas, lo que representó el 7,5%. El área del cuerpo celular fue mayor en neuronas nitrérgicas (412,29 ± 150.22) que en las teñidas con Giemsa (254,71 ± 63,32) y NADH-diaforasa positivas (243,98 ± 123,82).

Changes in Enteric Neurons of Small Intestine in a Rat Model of Irritable Bowel Syndrome with Diarrhea

BACKGROUND/AIMS: Physical and/or emotional stresses are important factors in the exacerbation of symptoms in irritable bowel syndrome (IBS). Several lines of evidence support that a major impact of stress on the gastrointestinal tract occurs via the enteric nervous system. We aimed to evaluate histological changes in the submucosal plexus (SMP) and myenteric plexus (MP) of the distal ileum in concert with the intestinal motor function in a rat model of IBS with diarrhea. METHODS: The rat model was induced by heterotypic chronic and acute stress (CAS). The intestinal transit was measured by administering powdered carbon by gastric gavage. Double immunohistochemical fluorescence staining with whole-mount preparations of SMP and MP of enteric nervous system was used to assess changes in expression of choline acetyltransferase, vasoactive intestinal peptide, or nitric oxide synthase in relation to the pan neuronal marker, anti-Hu. RESULTS: The intestinal transit ratio increased significantly from control values of 50.8% to 60.6% in the CAS group. The numbers of enteric ganglia and neurons in the SMP were increased in the CAS group. The proportions of choline acetyltransferase- and vasoactive intestinal peptide-immunoreactive neurons in the SMP were increased (82.1 ± 4.3% vs. 76.0 ± 5.0%, P = 0.021; 40.5 ± 5.9% vs 28.9 ± 3.7%, P = 0.001), while nitric oxide synthase-immunoreactive neurons in the MP were decreased compared with controls (23.3 ± 4.5% vs 32.4 ± 4.5%, P = 0.002). CONCLUSIONS: These morphological changes in enteric neurons to CAS might contribute to the dysfunction in motility and secretion in IBS with diarrhea.

Dietary Glutamate: Interactions With the Enteric Nervous System

BACKGROUND/AIMS: Digestion of dietary protein elevates intraluminal concentrations of glutamate in the small intestine, some of which gain access to the enteric nervous system (ENS). Glutamate, in the central nervous system (CNS), is an excitatory neurotransmitter. A dogma that glutamatergic neurophysiology in the ENS recapitulates CNS glutamatergic function persists. We reassessed the premise that glutamatergic signaling in the ENS recapitulates its neurotransmitter role in the CNS. METHODS: Pharmacological analysis of actions of receptor agonists and antagonists in concert with immunohistochemical localization of glutamate transporters and receptors was used. Analysis focused on intracellularly-recorded electrical and synaptic behavior of ENS neurons, on stimulation of mucosal secretion by secretomotor neurons in the submucosal plexus and on muscle contractile behavior mediated by musculomotor neurons in the myenteric plexus. RESULTS: Immunoreactivity for glutamate was expressed in ENS neurons. ENS neurons expressed immunoreactivity for the EAAC-1 glutamate transporter. Neither L-glutamate nor glutamatergic receptor agonists had excitatory actions on ENS neurons. Metabotropic glutamatergic receptor agonists did not directly stimulate neurogenic mucosal chloride secretion. Neither L-glutamate nor the metabotropic glutamatergic receptor agonist, aminocyclopentane-1,3-dicarboxylic acid (ACPD), changed the mean amplitude of spontaneously occurring contractions in circular or longitudinal strips of intestinal wall from either guinea pig or human small intestinal preparations. CONCLUSIONS: Early discoveries, for excitatory glutamatergic neurotransmission in the CNS, inspired enthusiasm that investigation in the ENS would yield discoveries recapitulating the CNS glutamatergic story. We found this not to be the case.

Morphoquantitative study of the submucous plexus (of Meissner) of the jejunum-ileum of young and old guinea pigs / Estudo morfoquantitativo do plexo submucoso (de Meissner) do jejuno-íleo de cobaias jovens e velhas

OBJECTIVE: To study the aging of submucous plexus of the small intestine (jejunum-ileum) of the guinea pigs from the quantitative, structural and ultrastructural perspective. METHOD: Chemical preparations of membrane of the jejunum-ileum of old and young animals with the use of light and electronic microscope. RESULTS: The ganglia of young animals presented between 1 and 56 neurons and the old animals presented from 1 to 30 neurons. The mean density of the ganglia by cm² in the young jejunum-ileum was of 551±36.89 and in the old one 413±11.86. The density of the neurons was 5011±291.11 neurons/cm² average in young animals and 2918±120.70 neurons/cm² in the old ones. The size of the neurons varied in both age groups. The collagen fibers in the ganglia of old animals they were condensed. Degenerated mitochondrias in the interior of the cell were frequent in the old animals. CONCLUSION: In submucous plexus of the jejunum-ileum there is a loss of 38 percent of the neurons with aging.

OBJETIVO: Estudar o envelhecimento do plexo submucoso do intestino delgado (jejuno-íleo) das cobaias do ponto de vista quantitativo, estrutural e ultra-estrutural. MÉTODO: Preparados de membrana do jejuno-íleo de animais jovens e velhos com a utilização de microscopia de luz e eletrônica. RESULTADOS: Os gânglios de animais jovens apresentaram entre 1 e 56 neurônios e os animais velhos apresentaram de 1 a 30 neurônios. A densidade média dos gânglios por cm² no jejuno-íleo jovem foi de 551±36,89 e no velho foi de 413±11,86. A densidade dos neurônios foi de 5011±291,11 neurônios/cm² em média nos animais jovens e 2918±120,70 neurônios/cm² nos velhos. O tamanho dos neurônios variou em ambos os grupos etários. As fibras colágenas nos gânglios de animais velhos estavam mais condensadas. Mitocôndrias degeneradas no interior da célula foram freqüentes nos animais velhos. CONCLUSÃO: No plexo submucoso do jejuno-íleo há uma perda de 38 por cento dos neurônios com o envelhecimento.

Histopathological Evaluation of Pediatric Intestinal Pseudo-Obstruction: Quantitative Morphometric Analysis of Pathological Changes in the Enteric Nervous System

BACKGROUND: This study was done to obtain comprehensive data on changes in the structural components of the enteric nervous system in pediatric patients with intestinal pseudo-obstruction (IPO). We evaluated routinely processed, in formalin-fixed tissues by quantitative morphometric analysis. In addition, we used formalin-fixed tissue to explore the possibility of using previously proposed diagnostic criteria to evaluate frozen serial sections for intestinal neuronal dysplasia (IND) type B and hypoganglionosis. METHODS: We analyzed data for 19 IPO cases. Morphometric analysis for quantification of ganglia and ganglion cells (GCs) was done for the myentric and the submucous plexus. In addition, we determined the presence of immature GCs and the distribution of nerve fibers and interstitial cells of Cajal (ICC). RESULTS: Nine patients showed combined hypoganglionosis, IND, and decreased ICC; others showed various combinations of these. Several morphometric factors were significantly different between patient groups as well as being different than the control group. CONCLUSIONS: Our pediatric IPO cases showed extensive overlapping of pathological findings. And the findings suggest the utility of using previously proposed morphometrically measured factors in multiple frozen sections as diagnostic criteria for IND type B and hypoganglionosis in formalin-fixed tissue.

Hirschsprung's Disease in Two Siblings

Hirschsprung's disease (HD) is one of the major pediatric gastrointestinal disease entities which is associated with an absence or lack of intrinsic ganglion cells in the myenteric and submucosal plexus in the gastrointestinal tract. It is commonly assumed to be a sex-modified multifactorial trait. The development of diagnostic and therapeutic modalities has been ongoing. Herein, we experienced two siblings who were confirmed as having HD histologically and were treated. We think further family evaluation regarding HD is needed. Also we could see a changing modality of diagnosis and treatment.

Idiopathic Intestinal Pseudo-obstruction in Infants Surgically Treated: Findings to Help Diagnose Intestinal Neuronal Dysplasia and the Significance of Surgical Treatment

PURPOSE: Intestinal neuronal dysplasia (IND) causes intestinal pseudo-obstruction and shares clinical features with Hirschsprung's disease. Diagnosis of IND involves histopathological features of an intestinal biopsy, but diagnostic criteria are controversial and optimal treatment is unclear. We determined the pathological findings for diagnosing IND in infants and the significance of surgical treatment. METHODS: We retrospectively studied 4 patients who received bowel surgery for an intestinal obstruction without a definite obstructive cause that were subsequently diagnosed as IND by postoperative pathology. The clinical history and results of immunohistochemistry for ganglion and nerve fibers (NCAM, NSE, cathepsin D, synaptophysin) were compared between patients and control cases. RESULTS: All 4 patients were premature babies with symptoms of poor oral intake and abdominal distention. Surgical treatment was segmental resection of the small bowel in one case, segmental resection of the small bowel and double-barreled ileostomy in one case with NEC, and a temporary ileostomy for decompression and appendectomy for biopsy in 2 cases. The first 2 patients died of sepsis and DIC, respectively. The postoperative course of the other 2 patients was excellent for long-term follow up (30+/-6months). Patients with IND showed significantly more submucosal giant plexuses and ganglia in the submucosal plexus, a higher percentage of giant plexus in the 20 submucosal plexus, as well as increased incidence of heterotopic ganglia in the lamina propria, bud-like ganglia, anisomorphic ganglia, and immature ganglia. CONCLUSION: Proper surgical treatment of persistent intestinal pseudo-obstruction, including IND, can affect the prognosis and recovery of bowel function, with positive pathological findings helpful for diagnosing IND in infancy.

Effects of ascorbic acid on the vasoactive intestinal peptide synthesis in the ileum submucous plexus of normal rats

RACIONAL: O envelhecimento é um processo deteriorativo que acomete o trato gastrointestinal, provocando alterações no número e tamanho dos neurônios do sistema nervoso entérico. A ação dos radicais livres nos neurônios entéricos é favorecida pela diminuição significativa de antioxidantes. OBJETIVO: Avaliar o efeito da suplementação com ácido ascórbico sobre os neurônios submucosos do íleo de ratos normais que produzem o peptídio intestinal vasoativo (VIP) por um período de 120 dias. MÉTODOS: Quinze ratos foram divididos em três grupos: controles com 90 dias, controles com 210 dias e tratados com ácido ascórbico com 210 dias. O ácido ascórbico foi administrado durante 16 semanas a partir de 90 dias de idade pela adição em água (1 g/L/dia). O íleo foi processado para obtenção de preparados totais empregados na realização de técnica imunoistoquímica para detectar a presença de corpos celulares e fibras VIP imunoreativas nos neurônios do plexo submucoso. O perfil celular e a imunoreatividade de 80 corpos celulares de neurônios VIP-érgicos de cada grupo estudado foi verificada. RESULTADOS: A suplementação com ácido ascórbico não alterou parâmetros fisiológicos tais como a água ingerida e alimento consumido nos três grupos estudados. Observou-se aumento significativo do perfil celular dos neurônios VIP-érgicos dos animais controles com 210 dias, quando comparados com os controles com 90 dias. O perfil celular dos neurônios VIP-érgicos no grupo de animais tratados com ácido ascórbico foi maior do que aqueles observados nos grupos controles. CONCLUSÃO: O ácido ascórbico teve efeito neurotrófico sobre os neurônios VIP-érgicos do íleo após 120 dias de suplementação.

Vaginal Delivery in Hirschsprung's disease complicating pregnancy / 대한산부인과학회지

Bowel obstruction is a rare complication of pregnancy. The usual causes include previous abdominal surgery, volvulus, intussusception, colonic neoplasm, or the enlarging uterus. Bowel obstruction secondary to uncorrected Hirschsprung's disease as a complication of pregnancy is difficult to diagnosis, its occurrence can have grave implications for both mother and fetus, and anticipation of dystocia. Hirschsprung's disease is diagnosed and treated in the neonatal period. Persistence of Hirschsprung's disease into adulthood is very rare and confirmed by rectal biopsy providing the absence of the ganglion cell in Auerbach and Meissner's plexus. We experienced vaginal Delivery in Hirschsprung's disease complicating pregnancy and report our own case study with a brief literature review.

Effect of acetyl-L-carnitine on Vip-ergic neurons in the jejunum submucous plexus of diabetic rats

The effect of the treatment with acetyl-L-carnitine (ALC) on neurons releasing the vasoactive intestinal polypeptide (VIP) of the submucous plexus in the jejunum of diabetic rats was the purpose of our investigation. Diabetes (DM) was induced by injecting streptozotocin endovenously (35mg/kg). After sacrificing the animals, the jejunum was collected and processed for VIP detection. Four groups were used: C (non-diabetic), CC (non-diabetic treated with ALC), D (diabetic), DC (diabetes treated with ALC). We analyzed the immunoreactivity and the cellular profile of 126 cell bodies. The treatment with ALC improved some aspects of DM. However, it promoted a small increase in the area of neurons from group CC, suggesting a possible neurotrophic effect. Neurons from groups D and DC showed a large increase in their cellular profile and immunoreactivity when compared to C and CC, suggesting a larger concentration of this neurotransmitter within the neurons that produce it. This observation constitutes a recurrent finding in diabetic animals, suggesting that ALC doesnot interfere in the pathophysiological mechanisms that unchain a higher production and/or neurotransmitter accumulation and increase the profile of the VIP-ergic neurons

Hirschsprung's Disease in Adults

Hirschsprung's disease is a disorder caused by the absence of ganglion cells in the colon and rectum. It has an incidence of 1 in 5000 births, the majority diagnosed and treated in the neonatal period due to symptoms of intestinal obstruction. Persistence of Hirschsprung's disease into adulthood is very rare. In such patients, prolonged periods of constipation are a common problem. For the diagnosis, a colon study and anorectal manometry are performed, and the presence of the disease is confirmed by an excisional biopsy proving the absence of the ganglion cell in Auerbach and Meissner's plexus. Although various surgical procedures have been performed, there is no obvious optimal choice for treatment of Hirschsprung's disease in adolescents and adults. We experienced two cases of Hirschsprung's disease, confirmed by a rectal biopsy, in 20-year patients. Prior to a definitive operation, a sigmoid loop colostomy was performed due to severe dilatation of the left colon and rectum. Six months later, one patient was treated using Duhamel's procedure, and the other by using a proctosigmoidectomy and coloanal anastomosis. No postoperative complications were observed, and the patients had bowel movements three to four times a day. Despite its infrequent incidence, adult Hirschsprung's disease should be suspected in patients who have had lifelong constipation. Several successful surgical treatments have been used for treatment of patients with adult Hirschsprung's disease. In our cases, the functional results of Duhamels' procedure and of a proctosigmoidectomy with coloanal anastomosis were satisfactory.

Terminal ileum submucous plexus: Study of the VIP-ergic neurons of diabetic rats treated with ascorbic acid

The aim of this study was to evaluate the effect of the ascorbic acid (AA) supplementation on the neurons that produce the vasoactive intestinal peptide (VIP) in the submucous plexus of the ileum of rat, four months after the induction of experimental diabetes mellitus with streptozotocin. Three groups of rats were used: C - control, D - diabetic, DA - diabetic receiving AA. We have measured the immunoreactivity and area of 80 cellular bodies of VIP-ergic neurons from each studied group. In the diabetic animals, we have observed hyperphagia, polydipsia, and an increase of glycemia and glycated hemoglobin. The VIP-ergic neurons have presented an increase of their immunoreactivity and the highest profiles when compared to the other groups. In the diabetic animals supplemented with AA it has been observed a small reduction in the glycemia and the water and food intake. We have also noticed smaller immunoreactivity in their VIP-ergic neurons, similar to what we have observed in the control group animals (group C)

Submucosal hypoganglionosis causing chronic idiopathic intestinal pseudo-obstruction.

A 39-year-old woman presented with recurrent symptoms suggestive of intestinal obstruction. She was put on total parenteral nutrition (TPN) and consequently developed sepsis and endocarditis. TPN was stopped and a venting enterostomy was performed. Biopsies of mucosa and submucosa were taken at surgery; immunohistochemistry for neuronal proteins, protein gene product 9.5 (PGP 9.5) and the glial S-100-protein was done. Many enlarged nerve fiber strands were found in the submucosa. Few small ganglia containing a small number of nerve cells could be observed, suggesting hypoganglionosis. This patient with chronic idiopathic intestinal pseudoobstruction of neurogenic type had a defect in the submucous plexus, whereas visceral neuropathies are usually characterized by defects of the myenteric plexus with normal submucous plexus.

Morphometry of submucous and myenteric esophagic plexus of dogs experimentally reinfected with Trypanosoma cruzi

We carried out a morphometric study of the esophagus of cross-bred dogs experimentally infected or consecutively reinfected with Trypanosoma cruzi 147 and SC-1 strains, in order to verify denervation and/or neuronal hypertrophy in the intramural plexus. The animals were sacrificed in the chronic stage, 38 months after the initial infection. Neither nests of amastigotes, nor myositis or ganglionitis, were observed in all third inferior portions of esophageal rings analyzed. No nerve cell was identified in the submucous of this organ. There was no significant difference (p>0.05) between the number, maximum diameter, perimeter, or area and volume of the nerve cells of the myenteric plexus of infected and/or reinfected dogs and of the non-infected ones. In view of these results we may conclude that the 147 and SC-1 strains have little neurotropism and do not determine denervation and/or hypertrophy in the intramural esophageal plexuses in the animals studied, independent of the reinfections

Morphology of the c-Kit-Immunoreactive Interstitial Cells of Cajal (ICC) in the Mouse Intestine / 대한해부학회지

Interstitial cells of Cajal (ICC) are the pacemalkers in gastrointestinal muscles, and these cells also mediate or transduce inputs from the enteric nervoius system. Immunolabelling of interstitial cells of ICC in intestinal wall is recently developed by using specific marker, anti-c-kit antibody. Immunohistochemistry was done for c-Kit-positive ICC network in attempt to provide a morphological basis for the mechanism regulating gastro-intestinal movement. Cryosection and whole-mount preparations of mouse ileum and colon were immunolabelled using the anti-c-Kit. Immunolabelled specimens were observed under a confocal laser scanning microscopy. According to three dimensional reconstruction study, it was found that the c-Kit-positive cells were widely distributed in the intestinal wall: (1) circular muscle layer, (2) myenteric plexus, (3) deep muscular plexus in ileum, (4) submucosal plexus and longitudinal muscle layer in colon. The characteristic profiles of ICC containing c-Kit-positive cells provide a morphological basis upon the mechanism regulating gastro-intestinal motility.

The Morphometric and Ultrastructural Study of Enteric Nervous System in Adult and Aged Rat Small Intestine / 대한해부학회지

This study was performed to investigate the morphometric and ultrastructural change in the adult and aged rat small intestine. The myenteric and submucous plexuses were stained by NADH-TR in the ileum of adult Sprague-Dawley rats (3 mo., 300~350 gm) and aged rats (24 mo., 500~550 gm). The neurons of myenteric and sumucous plexuses were divided into 3 groups depending on their cell body morphology. Type 1 cells were polygonal or round with abundant cytoplasm. Type 2 cells were spindle shaped and type 3 cells were small and round with scanty cytoplasm. The nerve cell numbers and sizes were measured using an image analyzer (VIDAS, Carl Zeiss, Co., Ltd.). Ultrastructural changes were observed by JEM-1200 EXII (JEOL Co., Ltd.) electron microscope. The result obtained are as followed: 1. In adult rats, majority of neuron population were type 3 and neuron density (total numbers/1 mm2) was more higher in submucous plexus than in the myenteric plexus. 2. Statistically significant loss of type 1 and type 2 neurons were in myenteric and submucous plexus of aged rat small intestine. 3. All types of neuron sizes were increased in aged myenteric and submucous plexuses. 4. Lipofusin granules were prominent in the cytoplasm of aged rat. Cell organelles were not shown degenerative change. These results suggest that type 1 and type 2 nerve cells which is originated from autonomic nerves were lost in aged rat small intestine. Ultrastructurally lipofusin granules were prominent in the cytoplasm of aged rat and the cell organelles were not degenerated.

Studies on the intrinsic nervous system of the wild rodent Calomys callosus digestive tract. II. The submucous plexus

The submucous plexus of the normal small and large intestine of Calomys callosus was studied by NADH and AChE histochemical techniques and by transmission and scanning electron microscopy. The plexus contains (X + SD) 7,488 + 293 neurons/cm2 in the duodenum, 5,611 + 836 in the jejunum, 2,741 + 360 in the ileum, 3,067 + 179 in the cecum, and 3,817 + 256 in the proximal colon. No ganglia or nerve cell bodies were seen in the esophagus, stomach, distal colon or rectum. The neurons are pear-shaped with a round or oval nucleus and the neuronal cell profile areas were larger in the large intestine than in the small intestine. Most of the neurons display intense AChE activity in the cytoplasm. AChE-positive nerve fibers are present in a primary meshwork of large nerve bundles and in a secondary meshwork of finer nerve bundles. At the ultrastructural level, the ganglia are irregular in shape and covered with fibroblast-like cells. The nucleoplasm of the neurons is finely granular with a few condensations of chromatin attached to the nuclear envelope. In the neuropil numerous varicosities filled with vesicles of different size and electron densities are seen. The pre- and post-synaptic membrane thickenings are asymmetric. Characteristic glial cells with oval nuclei and few organelles are numerous. These data provide a detailed description of this submucosal meshwork.

The Study of the Effect of Nerve Growth Factor on Intestinal Peristalsis in Streptozotocin-Induced Diabetic Rats / 대한해부학회지

Recently, it has been postulated that diabetic autonomic neuropathy is caused by reduction in availability of nerve growth factor (NGF) in enteric nervous system. This experiments were performed to determine the changes of the distribution of enteric neuropeptide by diabetes and these changes could be prevented by administration of NGF. Sprague Dawley rats (200~250gm) were made diabetic by a single intraperitoneal injection of streptozotocin 65 mg/kg in saline. Recombinant human NGF (Sigma, Co., Ltd.) were administered at a dose of 500ng/kg subcutaneously every day for consecutive 4 weeks after streptozotocin administration. After 4 weeks, rats were anesthetized with ether and perfused with 4% paraformaldehyde. ileum was dissected and prepared by whole mount preparation method. Prepared segments were immunostained for substance p, calcitonin gene-related peptide, vasoactive intestinal peptide, and galanin by PAP technique. For the observation of the interstitial cells of Cajal, segments were immersed in Champy-Maillet solution for 2 days Results obtained were as follows: 1. In myenteric plexus of diabetic rats, substance P-like and VIP-like immunoreactivity were not changed compared with that of the control group. CGRP-like and galanin-like immunoreactivity were decreased in diabetic group and immunoreactive cells for CGRP and galanin were also decreased 18.1% (P<0.01) and 43.7% (P<0.01) respectively. 2. In NGF administerd diabetic group, immunoreactivity of substance p, VIP, galanin in myenteric plexus were slightly increased and immunoreactive cells for substancre p, VIP, galanin were almost the same as that of the control group. However, immunoreactive cells for CGRP of myenteric plexus were not changed by NGF. 3. In submucous plexus of diabetic rats, immunoreactivity of all four neuropeptides(substance p, CGRP, VIP, galanin) were decreased compared with that of the control group. Immunoreactive cells for substance p, CGRP, VIP, and galanin were also decreased in 38.8%, 77.6%, 33.0%, and 35.7%, respectively (P<0.01). 4. In NGF administered diabetic group, immunoreactivities of substance p, VIP and galanin in submucous plexus were increased and the immunoreactive cells were increased significantly compared to diabetic group. However, immunoreactive cells for CGRP of submucous plexus were not changed by NGF. 5. Interstitial cells of Cajal of diabetic group were decreased 7.4% ovoidal cells (A type) and 28.3% round cells (B type) In NGF administered group, the morphology and the number of ICC were not different to the control group. With the above results, it could be assumed that NGF prevent the damage of neurotransmitter and ICC in enteric nervous system.

Rat colon epithelium response to hypoxia is modified by intrinsic innervation blockade

Background/Aim: Short-circuit current (Isc) and transepithelial potential difference (PD) of rat distal colon decrease during acute hypoxia and overshoot on reoxygenation. It is not known whether tonic intrinsic nervous activity may influence these responses. Methods: Preparations lacking the submucosal plexus (isolet mucosa) and preparations retaining it (mucosa-submucosa) were mounted in Ussing chambers at 37 degrees Celsius and gassed with 95 percent O2 -5 percent CO2; Isc and PD were monitored. A 5-min hypoxia with 95 percent N2-5 percent CO2 was followed by reoxygenation. The procedure was repeated in the presence of the nervous blocking agent, tetrodotoxin (10(-6)M) in the serosal side of the chamber. Results: In the isolated mucosa (n=10) hypoxia reduced Isc by -55 + 5 percent and PD by -54 + 6 percent below baseline; reoxygenatory overschoots were, respectively, + 60 + 17 percent and + 16 percent. Tetrodotoxin slightly and transiently reduced baseline Isc (-16 + 2 percent) and PD (-14 + 3 percent), with a small resistivity increase. It did not significatively modify the responses to responses to either hypoxia or reoxygenation. In mucosa-submucosa preparations (n=9) hypoxia reduced Isc (-54 + 8 percent) and PD (-61 + 4 percent). On reoxygenation Isc and PD were increased, respectively, +30 + 5 percent and +19 + 6 percent over baseline. Tetrodotoxin reduced baseline Isc (-59,6 + 5 percent) and PD (61,3 + 6 percent). It enhanced hypoxic Isc and PD decreases (-80 + 5 percent), but not the reoxygenatory overschoots. Conclusions: 1) Tetrodotoxin affects baseline Isc and PD more intensely in submucosal plexus innervated preparations than in the isolated mucosa. 2) The epithelial electrical response to acute hypoxia appears to be modulated by tonic neural activity.

Estudo quantitativo e qualitativo dos plexos de Auerbach e Meissner do esôfago de cäes inoculados com o Trypanosoma cruzi / A quantitative and qualitative study of the Auerbach and Meissner plexus in dogs inoculated with Trypanosoma cruzi

A quantitative and qualitative study was conducted on the Auerbach and Meissner plexuses of the esophagus of four chagasic dogs sacrificed during the acute phase of infection. Ganglionitis and periganglionitis of the Auerbach plexus ranged from mild to moderate and induced significant neuronal lesions, especially in two animals. The ganglions of the Meissner plexus were observed in small number which did not permit any analysis. Mild or moderate myositis was observed mainly in the lower third of the esophagus and was rarely associated with amastigote nests. Ganglion and neuron counts did not demonstrate denervation. Although the formation of megaesophagus was not induced in any dog, lesions of the Auerbach plexus and myocells of the esophagus were observed during the acute phase of chagasic infection. To our knowledge, this is the first systematic quantitative and qualitative study of the Auerbach and Meissner plexuses of the esophagus in experimental trypanosomiasis cruzi.