Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01275 (glucagon)
 26,492 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The insulin response to oral glucose, tolbutamide, arginine, pancreozymin and cerulein was studied in a group of subjects with insuloma and a group of normal control subjects. The same parameters were studied in a small number of cases after administration of secretin and gastrin. The glucagon response (IRG) to arginine, pancreozymin and cerulein was also studied. In subjects with insulomas plasma IRI values after oral glucose, tolbutamide and pancreozymin, starting from elevated basal levels, reached high absolute levels though the increase above basal levels did not differ significantly from normal. After cerulein plasma IRI values increased in some insuloma patients but not in normal subjects. After arginine the plasma IRI increase above basal levels was significantly lower than normal in patients with insulomas. The glucagon response to arginine was normal in the patients with insulomas; these patients showed a clearcut glucagon response to cerulein and a very irregular response after pancreozymin.
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PMID:Response of islet cell tumors to enterohormones. 17 27

The presence and development of immunoreactive gastrin (IRGa) in the fetal and neonatal pancreas and pyloric antrum of the rat were studied. IRGa appeared in both organs at least as early as the 16th day of fetal life. Antral IRGa increased rapidly and continuously in the neonatal period, while pancreatic IRGa concentration increased and was maintained at a relatively constant level from days 5 to 35. Monolayer cell cultures of the neonatal rat pancreas were used to evaluate the role of cyclic AMP mediated release of gastrin. The addition of N6,O2'-dibutyryl cyclic AMP (4 mM) or theophylline (4 mM) to the culture medium induced significant release of gastrin. The stimulation of adenylate cyclase with cholera toxin (10 ng/ml) also resulted in significant gastrin release. Long-term cultures (18-24 days) were shown to release gastrin continuously at a relatively constant rate. The cellular localization of pancreatic gastrin in 7-day-old cultures was performed by immunological techniques, using fluorescein-labeled antibodies to gastrin. The gastrin-containing cells were located at the periphery of most of the endocrine cell clusters. Immunofluorescence techniques for insulin and glucagon also showed that the alpha cells had a similar peripheral distribution, although they were more frequent in number. In contrast, insulin-containing cells were numerous and were present in all areas of the endocrine cell clusters. The studies support the following conclusions: a) Gastrin is present in the rat pancreas, even as early as late fetal life; b) Gastrin-producing cells are present and functionally competent in monolayer cell cultures of the neonatal rat pancreas for prolonged periods of time (24 days); c) Gastrin is released from these cells when intracellular levels of cyclic AMP are increased; d) By immunofluorescence methods, the gastrin-producing cells in pancreatic cell cultures are found to be located at the periphery of the endocrine cell clusters.
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PMID:Gastrin in the perinatal rat pancreas and gastric antrum: immunofluorescence localization of pancreatic gastrin cells and gastrin secretion in monolayer cell cultures. 18 64

The islet cell tumors of the pancreas are now known to produce a variety of polypeptides in addition to insulin. These include glucagon, serotonin, corticotropin, melanocyte-stimulating hormone, gastrin and a secretinlike hormone that may be VIP or a combination of such polypeptides. The development and wide availability of the newer immunoassays for the various recognized hormones as well as candidate hormones of the gut will simplify the diagnosis of these challenging tumors, which up until this time have produced symptoms that were bizarre and often fatal to the patient.
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PMID:Tumors of the islets of Langerhans. 18 90

Angiographic findings in one giant cell carcinoma, one cystadenocarcinoma, one poorly vascularized mucinous cystadenocarcinoma, as well as in two avascular (gastrin- and glucagon-producing) islet-cell tumors of the pancreas are described. Two hypervascularized islet-cell tumors are presented for comparison and a case of tumorous chronic pancreatitis in a child is reported because ot its rarity. The aggressiveness of the giant cell carcinoma of the pancreas was demonstrated by its expansive growth. In the case of cystadenocarcinoma angiography revealed the tumor with hepatic metastases not diagnosed at explorative laparotomy. The relative hypovascularity in the case of mucinous cystadenocarcinoma was unusual. Both avascular islet-cell tumors simulated a pancreatic pseudocyst and the final diagnosis was made only by immunoassay. Chronic pancreatitis in a child presented with marked hypervascularization.
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PMID:Angiographic findings in some rare pancreatic tumors. 18 40

With combined immunofluorescent, cytochemical and electron microscopic investigations the enterochromaffin cell system has been differentiated into 5 distinct endocrine cell types in the human stomach and into 8 cell types in the intestine. These endocrine cells are probably of neuroectodermal origin and belong to the APUD (amine precursor uptake and decarboxylation)-system. Maximal gastrointestinal hormone concentrations as determined by tissue extracts correlate fairly well to the location of each endocrine cell type in various segments of the gastrointestinal tract. In certain gastroenteropathies the pathophysiological disturbances can be explained by pathomorphological alterations of the disseminated endocrine cells. 1. The gastrin-producing G-cell is the predominating endocrine cell in the gastric antrum. Besides immunocytochemistry the G-cell can be demonstrated with argyrophilic reaction (Grimelius, 1968), masked metachromasia and leadhematoxylin. The ultrastructural features are variable, depending on functional activity. The secretory granules are usually only slightly osmiophilic, measuring 200 till 250 nm in diameter. By some working groups a positive immunofluorescence with gastrin-antisera has been demonstrated in A1- or D-cells of the pancreatic islets. However, numerous negative results have been reported, too. Considering physiological conditions, a gastrin-secretion of the human pancreatic islets has not been secured without doubt. 2. The EC-cell produces serotonin and in the intestine motilin, too. Besides the formaldehyde-induced fluorescence, these cells can be demonstrated with diazonium and argentaffin reactions, less specific with argyrophilic methods. Ultrastructurally the EC-granules are easily differeniated from the other endocrine cells by their pronounced osmiophilia and pleomorphism. In experimental conditions the EC-cells demonstrate species- and site-specific alterations. With reserpine no ultrastructural changes were demonstrable in EC-cells of the rat. However, marked ultrastructural alterations with an increase of the hormone-producing organelle system were noticed after administration of parachlorophenylalanine (PCPA) which interferes with serotonine synthesis; 5. The gastric D-cells are characterized by large secretory granules similar to pancreatic D-cells. They secrete the HCl-inhibitory peptide somatostatin. 4. The D1-cell is a cell type with unknown function. The cytoplasm contains small granules with variable electron density. According to most authors, they represent a distinct cell type and not just a variant of the G-cells. It may be very difficult, however, to separate certain forms of D1-cells from functionally altered G-cells. 5. The A-cell can be found in the gastric mucosa of certain animal species, where it has been demonstrated by immunocytochemistry with antisera to gut-glucagon. This cell type does not occur in the human gastric mucosa. 6...
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PMID:[Pathomorphologic studies of the endocrine cells in the gastrointestinal mucosa. Physiology, cytochemistry and ultrastructure (author's transl]. 19 Aug 18

Up to seven endocrine cell types have been identified ultrastructurally in the pancreas, including glucagon A cells, insulin B cells, somatostatin D cells, pancreatic peptide F cells and 5-hydroxytryptamine EC cells. In addition, D1 cells, which have been proposed as the cell type producing VIP and possible P cells of unknown function are seen. Various patterns of endocrine cell differentiation have been found in 20 endocrine pancreatic tumours. Well and poorly differentiated B cells have been identified in 6 insulinomas, diagnostic G cells in 3 out of 7 gastrinomas, D1 and/or F cells in 7 diarrheogenic tumours. Moreover, cells apparently unrelated to the prevalent clinical syndrome have been noted in 8 of the 20 tumours. Granular non diagnostic cells (poorly diagnostic gastrin cells? D1 cells?) were particularly frequent in gastrinomas; agranular or poorly granular cells, either by "active" or "Stem cell" type, were present in nearly all tumours, particularly in diarrheogenic tumours, gastrinomas and malignant insulinomas. A cytological classification of pancreatic endocrine tumours is proposed.
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PMID:The endocrine cells of the pancreas and related tumours. Ultrastructural study and classification. 19 45

Electrical stimulation (10 V, 10 Hz, 3 min) of both dorsal and ventral vagal trunks of the isolated canine stomach perfused with whole blood induced strong gastric contractions, transient release of cyclic GMP and marked release of gastrin. No gastric-glucagon release was elicited either at 'normal' (4.8 +/- 0.1 mmol/l) or at low (1.5 +/- 0.1 mmol/l) concentrations of blood glucose. It is concluded that, in conditions effective for the stimulation of gastrin release, electrical stimulation of the vagus nerves does not stimulate glucagon release from the isolated perfused dog stomach. Thus one of the well-accepted mechanisms controlling pancreatic-glucagon secretion, vagal stimulation, is ineffective on gastric-glucagon release.
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PMID:Vagal stimulation and its role in eliciting gastrin but not glucagon release from the isolated perfused dog stomach. 20 43

In dispersed mucosal cells from guinea pig stomach cyclic AMP was increased 4-fold by theophylline, 5-fold by prostaglandin E2, and 10- to 15-fold by histamine. Theophylline augmented the increase in cellular cyclic AMP caused by histamine or prostaglandin E1 and the actions of histamine and prostaglandin E1 were additive. Cellular cyclic AMP was not altered by carbachol, gastrin, secretin, vasoactive intestinal peptide, glucagon, insulin or the octapeptide of cholecystokinin. Metiamide or diphenhydramine but not atropine inhibited the increase in cellular cyclic AMP caused by histamine, but did not alter the concentration of cyclic AMP in control cells or in cells incubated with theophylline or prostaglandin E1.
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PMID:Cellular cyclic AMP in dispersed mucosal cells from guinea pig stomach. 20 34

A case of chronic secretory diarrhea with elevated plasma vasoactive intestinal peptide (VIP) and serum gastrin levels is described. Plasma secretin, glucagon, insulin, and cyclic adenosine and guanine monophosphate (cAMP and (CGMP) concentrations were normal. Administration of a prostaglandin synthetase inhibitor failed to decrease the volume of diarrhea. There was no evidence of laxative abuse, antral cell hyperplasia, gastric hypersecretion, or pancreatic hypersecretion. The pancreatic histology was interpreted as islet cell hyperplasia. Jejunal tissue cAMP and cGMP concentrations were in the same range as those obtained from three control subjects. This report suggests that cyclic nucleotides may not mediate intestinal secretion in hormone-induced diarrhea.
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PMID:Normal jejunal cyclic nucleotide content in a patient with secretory diarrhea. 21 Jul 31

Thirty pancreatic islet cell tumours were histologically classified and analysed for their possible peptide hormone content using the immunohistoperoxidase method. Seven tumours contained insulin, six tumours contained gastrin and eight tumours contained glucagon. One tumour contained all three hormones. In the insulin and gastrin-containing tumours, the cells were usually arranged in solid nests of cells, with tubular and acinar formations in about half the cases. In the glucagon-containing tumours the cells were mainly arranged in anastomosing ribbons consisting of one of two layers of small cells. Most of the hormone-containing tumours were argyrophilic using Grimelius' silver reaction. All but one of the glucagon-containing tumours were incidental findings at autopsy. About half of the other tumours had metastasized. It is concluded that a relation exists between the histological pattern of growth and immunohistochemically defined endocrine function of pancreatic islet cell tumours.
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PMID:Morphology and immunohistochemically-defined endocrine function of pancreatic islet cell tumours. 21 2


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