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Query: UMLS:C0007570 (celiac disease)
 13,091 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The autonomic nervous system of mammals displays extensive neurotransmitter diversity. The guinea-pig sympathetic nervous system has served as a model for in vivo studies of neurotransmitter co-expression. We have developed methods for the dissociation and long-term culture of adult guinea-pig prevertebral sympathetic ganglia. The neurotransmitter properties of cultured adult guinea-pig sympathetic neurons from the celiac and superior mesenteric ganglia were examined. Cultured principal neurons were found to display many of their in vivo neurotransmitter characteristics, including catecholamine-specific histofluorescence and immunoreactivity for tyrosine hydroxylase and the neuropeptides, neuropeptide Y, somatostatin and vasoactive intestinal polypeptide. In addition, the cultures of both ganglia displayed the various neurotransmitter characteristics in approximately the same percentage of the cultured neurons as reported in in vivo studies. A small percentage of principal neurons and many small, intensely fluorescent-like cells labeled with antibodies against 5-hydroxytryptamine. Many of the principal neurons were found to bear 5-hydroxytryptamine3 receptors, suggesting a possible role for this neurotransmitter in neuron-neuron and small, intensely fluorescent cell-neuron transmission. We conclude that adult guinea-pig sympathetic neurons retain their neurotransmitter phenotypes when grown in dissociated cell culture. These properties include the co-expression of the classical transmitters, norepinephrine, 5-hydroxytryptamine and neuropeptides. This culture preparation will prove to be valuable in future studies on the functional properties of these neurons and their development.
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PMID:Neurotransmitter properties of guinea-pig sympathetic neurons grown in dissociated cell culture--I. Adult neurons. 790 16

We report here the neurotransmitter characteristics of neurons cultured from the same ganglia of fetal and embryonic guinea-pigs. Both the celiac ganglion and the superior mesenteric ganglion were examined. In a previous paper we described the neurotransmitter properties of adult guinea-pig prevertebral sympathetic neurons grown in dissociated cell culture, including the expression by these cells of immunoreactivity for tyrosine hydroxylase, neuropeptide Y and somatostatin. Tyrosine hydroxylase immunoreactivity was ubiquitously expressed in all fetal embryonic cultures, as was the case for adult neurons. Fetal-derived celiac and superior mesenteric gangli neurons displayed neuropeptide Y and somatostatin immunoreactivity in the same percentage of neurons as in adult cultures but at markedly lower levels. Embryonic neurons also expressed somatostatin immunoreactivity in roughly the same proportion of neurons as in adult and fetal cultures; however, the expression of neuropeptide Y immunoreactivity in both celiac and superior mesenteric gangli cultures was significantly different. Specifically, neuropeptide Y immunoreactivity in embryonic celiac cultures was greatly reduced in both the number of positive-labeled neurons and the amount of immunoreactive product, while neuropeptide Y immunoreactivity in embryonic superior mesenteric gangli cultures was markedly increased compared to their adult and fetal counterparts. The expression of neuropeptide Y immunoreactivity in celiac neurons was found to be specifically elevated by culturing the neurons in medium conditioned by disassociated vascular cells, this treatment having no effect on tyrosine hydroxylase or somatostatin immunoreactivity. Heart cell-conditioned medium did not effect neuropeptide Y or somatostatin immunoreactivity, although it did result in a significant reduction of tyrosine hydroxylase immunoreactivity and an increase in 5-hydroxytryptamine immunoreactivity. We conclude that the expression of neuropeptide Y immunoreactivity develops independently in cultures of adult and near-term fetuses but that embryonic neurons require interactions with target cells to express this phenotype. Neuropeptide Y immunoreactivity can be induced in embryonic sympathetic neurons by a target-derived factor(s).
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PMID:Neurotransmitter properties of guinea-pig sympathetic neurons grown in dissociated cell culture--II. Fetal and embryonic neurons: regulation of neuropeptide Y expression. 790 17

1. Sympathetic neurons in superior mesenteric ganglion and inferior mesenteric ganglion (IMG) isolated from guinea pigs were classified as tonic, phasic, or long after hyperpolarizing (LAH) on the basis of their discharge characteristics and the different types of potassium currents recorded from them with the soma under single-microelectrode voltage clamp. 2. Passive electrical properties showed a progressive increase in input resistance across the prevertebral ganglia in the rostrocaudal direction when compared with those previously reported for the same classes of neurons in celiac ganglia (CG). 3. The proportions of tonic, phasic, and LAH neurons changed markedly in a rostrocaudal progression from 37, 14, and 49%, respectively, in the CG to 80, 18, and 2%, respectively, overall in the IMG. 4. Three populations of neurons distinguished immunohistochemically by their content of somatostatin (SOM), neuropeptide Y (NPY), or neither neuropeptide were present in different proportions in each prevertebral ganglion. The proportions of SOM, NPY, and no peptide neurons changed from 27, 34, and 39%, respectively, in the CG to 45, 20, and 35%, respectively, in the IMG. There was no significant difference in these distributions between the sexes. 5. Individual electrophysiologically characterized neurons were filled with biocytin and later examined for SOM immunoreactivity. All SOM-positive neurons (9/9) in the CG but only 7/10 in the IMG were tonic, whereas SOM-negative neurons were classified in all electrophysiological classes. 6. Other than this one group of sympathetic neurons (constituting nearly 30% of neurons in both CG and IMG), the three electrophysiological classes do not correlate directly with the three neurochemical types so far identified. This is consistent with the existence of more than three functional groups of sympathetic neurons in the prevertebral ganglia. The findings also suggest that a major inhibitory effect on mucosal secretion, as well as on motility, is mediated by peripheral reflex pathways along much of the length of the gastrointestinal tract.
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PMID:Relation between electrophysiological class and neuropeptide content of guinea pig sympathetic prevertebral neurons. 809 41

The mechanisms and site of action of somatostatin-induced inhibition of pancreatic enzyme secretion were investigated using different stimulants of pancreatic secretion acting on different sites in anesthetized rats. Administration of graded doses of somatostatin-14 resulted in a dose-related inhibition of pancreatic protein secretion evoked by 2-deoxy-D-glucose, a central vagal stimulant that acts by stimulating the dorsal vagal nuclei. The lowest effective dose of somatostatin-14 was 1.0 microgram.kg-1 x h-1; maximal effective dose was 25 micrograms.kg-1 x h-1, which resulted in complete inhibition of protein output. Similarly, somatostatin-14 at a dose of 25 micrograms.kg-1 x h-1 also completely inhibited pancreatic protein secretion in response to a physiological concentration of cholecystokinin octapeptide (CCK-8), which acts via a vagal afferent pathway. In contrast, pancreatic protein outputs evoked by bethanechol, which directly stimulates pancreatic muscarinic receptors, or electrical stimulation of the vagal trunk, which activates the vagal efferent pathway, were unaffected by somatostatin-14. In separate studies, we demonstrated that perivagal treatment with the sensory neurotoxin capsaicin impaired pancreatic responses to CCK-8 but had no effect on the inhibitory action of somatostatin-14 on pancreatic secretion evoked by 2-deoxy-D-glucose, ruling out an effect of somatostatin on the vagal afferent pathway. Similarly we also demonstrated that perineural capsaicin treatment of the celiac-superior mesenteric ganglia did not affect the inhibitory action of somatostatin. These findings indicate that somatostatin inhibits 2-deoxy-D-glucose- and CCK-8-evoked pancreatic enzyme secretion via a vagal pathway.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Somatostatin inhibits pancreatic enzyme secretion at a central vagal site. 810 34

To investigate the role of sympathoadrenergic activity on glucose production (Ra) during exercise, eight healthy males bicycled 20 min at 41 +/- 2 and 74 +/- 4% maximal O2 uptake (VO2max; mean +/- SE) either without (control; Co) or with blockade of sympathetic nerve activity to liver and adrenal medulla by local anesthesia of the celiac ganglion (Bl). Epinephrine (Epi) was in some experiments infused during blockade to match (normal Epi) or exceed (high Epi) Epi levels during Co. A constant infusion of somatostatin and glucagon was given before and during exercise. At rest, insulin was infused at a rate maintaining euglycemia. During intense exercise, insulin infusion was halved to mimic physiological conditions. During exercise, Ra increased in Co from 14.4 +/- 1.0 to 27.8 +/- 3.0 mumol.min-1.kg-1 (41% VO2max) and to 42.3 +/- 5.2 (74% VO2max; P < 0.05). At 41% VO2max, plasma glucose decreased, whereas it increased during 74% VO2max. Ra was not influenced by Bl. In high Epi, Ra rose more markedly compared with control (P < 0.05), and plasma glucose did not fall during mild exercise and increased more during intense exercise (P < 0.05). Free fatty acid and glycerol concentrations were always lower during exercise with than without celiac blockade. We conclude that high physiological concentrations of Epi can enhance Ra in exercising humans, but normally Epi is not a major stimulus. The study suggests that neither sympathetic liver nerve activity is a major stimulus for Ra during exercise. The Ra response is enhanced by a decrease in insulin and probably by unknown stimuli.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Regulation of hepatic glucose production during exercise in humans: role of sympathoadrenergic activity. 836 97

The occurrence of vasoactive intestinal polypeptide (VIP), peptide histidine-isoleucine (PHI), calcitonin gene-related peptide (CGRP), substance P (SP), somatostatin (SOM), galanin (GAL) and enkephalins (ENK) is studied in the human celiac/superior mesenteric ganglionic complex of pre- and full-term newborns, and adult subjects by means of immunohistochemistry. The antisera used labelled nerve fibres and terminal-like networks for each examined peptide, as well as VIP- and SOM-positive postganglionic neurons. Differences in the relative amount and density of the structures immunoreactive to the various peptides were observed. Moreover, variations in the amount and type of labelled elements were appreciable for each peptide when specimens from subjects at perinatal and adult ages were compared. Double-labelling immunofluorescence for SP and each other peptide showed that co-localization with SP is very frequent for CGRP, moderate to scarce for GAL and SOM, and rare to absent for PHI, VIP and ENK. VIP-, ENK- and CGRP-immunolabeled perikarya bearing the morphological features of the small intensely fluorescent (SIF) cells occurred in the organ. The presence of a paraganglion in one of the specimens examined allowed the detection of VIP- and ENK-positive cell bodies and VIP-, ENK-, SP- and GAL-like immunoreactive varicose nerve fibres in it. The results obtained provide substantial morphological data in support of the involvement of the examined peptides in the chemical interneuronal signalling in the human celiac/superior mesenteric ganglia.
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PMID:Neuropeptides in the human celiac/superior mesenteric ganglionic complex: an immunohistochemical study. 847 42

To evaluate the effect of bradykinin (BK) on rat islet alpha, beta, and delta cells, the rat pancreas was perfused in situ with BK (1 mumol/L) for 30 minutes via a cannula placed in the celiac artery. Insulin, glucagon, and somatostatin concentrations in the effluent were measured to determine the effect of BK on the secretion of these hormones. The BK concentration of the rat pancreas was also measured. Basal secretion of insulin, glucagon, and somatostatin in medium containing 6 mmol/L glucose was maintained at 6.5 +/- 0.5 ng/mL 124 +/- 8 pg/mL, and 511 +/- 22 pg/mL (n = 12), respectively. BK (1 mumol/L) induced a transient peak that was 3.7-fold of the baseline concentration within 3 minutes, followed by a sustained level that was approximately 50% higher than baseline. BK also transiently increased glucagon secretion with a peak that was 1.7-fold of the baseline concentration within 3 minutes, without a sustained secretion phase. BK caused a reduction in somatostatin secretion within 3 minutes to a level of 60% to 70% of the baseline concentration. The BK concentration of the rat pancreas was 3.42 +/- 1.45 micrograms/g protein (n = 5), which was approximately 3 mumol/L. We concluded that BK stimulated insulin secretion, transiently increased glucagon secretion, and decreased somatostatin secretion during the 30-minute perfusion of the rat pancreas.
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PMID:The effect of bradykinin on secretion of insulin, glucagon, and somatostatin from the perfused rat pancreas. 932 91

Coeliac disease is associated with intestinal lesion. This lesion causes architectural derangement of the mucosa in the form of villus atrophy, increased crypt length and increased volume of the lamina propria. Several changes in the intestinal endocrine cells have been reported over the years, e.g. the number of secretin cells and increased numbers of GIP, CCK/gastrin, motilin, and serotonin cells. There is no consensus about the nature of the changes in somatostatin-cells. It has been postulated that the changes in the endocrine cells are a selective process to meet the new demands exerted by the dramatic decrease in intestinal absorptive area. It has been speculated further that the changes in the endocrine cells would cause an incomplete digestion of the ingested food and its rapid elimination from the intestine. These changes may be responsible for the diarrhoea and steatorrhoea that occur in patients with coeliac disease.
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PMID:The nature and implication of intestinal endocrine cell changes in coeliac disease. 981 May 3

Peptidergic mechanisms influencing the resistance of the gastrointestinal vascular bed of the estuarine crocodile, Crocodylus porosus, were investigated. The gut was perfused in situ via the mesenteric and the celiac arteries, and the effects of different neuropeptides were tested using bolus injections. Effects on vascular resistance were recorded as changes in inflow pressures. Peptides found in sensory neurons [substance P, neurokinin A, and calcitonin gene-related peptide (CGRP)] all caused significant relaxation of the celiac vascular bed, as did vasoactive intestinal polypeptide (VIP), another well-known vasodilator. Except for VIP, the peptides also induced transitory gut contractions. Somatostatin and neuropeptide Y (NPY), which coexist in adrenergic neurons of the C. porosus, induced vasoconstriction in the celiac vascular bed without affecting the gut motility. Galanin caused vasoconstriction and occasionally activated the gut wall. To elucidate direct effects on individual vessels, the different peptides were tested on isolated ring preparations of the mesenteric and celiac arteries. Only CGRP and VIP relaxed the epinephrine-precontracted celiac artery, whereas the effects on the mesenteric artery were variable. Somatostatin and NPY did not affect the resting tonus of these vessels, but somatostatin potentiated the epinephrine-induced contraction of the celiac artery. Immunohistochemistry revealed the existence and localization of the above-mentioned peptides in nerve fibers innervating vessels of different sizes in the gut region. These data support the hypothesis of an important role for neuropeptides in the control of the vascular bed of the gastrointestinal tract in C. porosus.
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PMID:Peptidergic control of gastrointestinal blood flow in the estuarine crocodile, Crocodylus porosus. 984 48

A 59-year-old woman was hospitalized due to a 1-year history of diarrhea and weight loss. Echography and computed tomography of the abdomen revealed a 10 x 7 cm solid mass in the tail of the pancreas and gallstones, while selective celiac angiography revealed the presence of a hypervascular mass. High levels of somatostatin and calcitonin were detected in the plasma, 70 pg/ml (normal range <28 pg/ml) and 5550 pg/ml (normal range 37 +/- 8 pg/ml), respectively. This tumor was thus removed by means of a distal pancreatectomy and a splenectomy. After the pancreatic tumor was removed, the elevated levels of plasma somatostatin and calcitonin returned to the normal ranges, and the persistent diarrhea also dramatically disappeared. A postoperative immunohistochemical study showed the tumor cells to be diffusely positive for somatostatin and calcitonin. These results clearly indicate this patient to be a case of calcitonin-producing pancreatic somatostatinoma.
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PMID:Calcitonin-producing pancreatic somatostatinoma: report of a case. 987 49


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