Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01350 (gastrin)
 9,683 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The distributions of acid alpha1-glycoprotein, alpha1-fetoprotein, beta-galactosidase and gastrin in gastric carcinoma and gastric ulcer as well as in the neighbourhood of these lesions were studied by means of immunohistochemical methods on imprint preparation. We could not find significant differences between gastric carcinoma and the nonneoplastic lesions, except for the acid alpha1-glycoprotein. The results of this first study indicate that the immunochemical and immunohistological assay of acid alpha1-glycoprotein might be of practical value in diagnosing malignant changes of gastric mucosa.
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PMID:[Immunohistochemical studies on non neoplastic and neoplastic gastric mucosa. Determination of embryonic and specific antigens (author's transl)]. 5 51

In female rats aspirin-induced gastrin mucosal damage was increased and glycoprotein synthesis decreased by fasting and by insulin administration. Glucose added to the drinking water during the fasting period reduced mucosal damage and increased glycoprotein synthesis to control levels. Alloxan diabetes did not affect mucosal damage or glycoprotein synthesis. Alloxan diabetes plus insulin restored blood glucose levels to normal, and susceptibility to aspirin damage and glycoprotein synthesis were also normal. Alloxan diabetes plus fasting restored blood glucose levels to normal but increased aspirin-induced mucosal damage and reduced glycoprotein synthesis. In vitro incubation of gastric mucosal homogenates showed that diburyryl cyclic AMP and theophylline inhibited glycoprotein synthesis but dibutyryl cyclic GMP had no significant effects. The importance of an adequate supply of glucose to the gastric mucosa and the effects of cyclic nucleotides on glycoprotein synthesis are discussed.
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PMID:Effects of blood glucose levels on aspirin-induced gastric mucosal damage. 20 Jan 38

Key components of the mucous gel include the glycoprotein mucin and surface-active phospholipids. In the present study, mucin production and release of the surface-active phospholipid phosphatidylcholine (PC) into the medium were measured with an isolated canine mucous cell culture system. Stimulation of glycoprotein synthesis in response to 10(-4) mol/L histamine (160% +/- 9% of control, P < 0.01), 10(-6) mol/L gastrin (129% +/- 7%, P < 0.01), and 10(-6) mol/L carbamylcholine (129% +/- 7%, P < 0.01) was observed by metabolic labeling, whereas prostaglandin E2 (PGE2) had no effect. The effect of histamine was blocked by the H2 receptor antagonist cimetidine but not the H1 receptor antagonist diphenhydramine (P < 0.01). Activators of adenylate cyclase and cyclic adenosine monophosphate analogs significantly stimulated mucin synthesis (P < 0.05). A 7.8% +/- 1.7% increase in mucin above basal levels after 24 hours was observed with a solid-phase immunoassay in control wells, whereas histamine, gastrin, and carbamylcholine increased total mucin by 14% +/- 0.7%, 17% +/- 4.3%, and 20.4% +/- 4%, respectively (all P < 0.01), and PGE2 had no significant effect. PC release was stimulated by the administration of histamine, carbamylcholine, gastrin (108%-110% of control, P < or = 0.05), and PGE2 (120% of control, P < 0.01). The acid secretagogues histamine, gastrin, and carbamylcholine stimulated mucin synthesis and PC release. PGE2 has no direct role in the synthesis of canine gastric mucin but stimulates release of surface-active phospholipids. The mechanisms responsible for acid secretion provide for the coordinated production of the primary layer of defense against the injurious effects of low pH.
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PMID:Regulation of canine gastric mucin synthesis and phospholipid secretion by acid secretagogues. 850 Jul 55

Various endocrine cells can be stained by the argyrophil reaction of Grimelius. This silver stain has recently been attributed to chromogranin A, an acidic glycoprotein, that is present in many endocrine cells. Using serial sections of plastic-embedded tissues (adrenal medulla, pancreas, gastric mucosa) various endocrine cells were investigated for their content of chromogranin A immunoreactivity and for their argyrophilia. The findings in four species (man, cattle, pig, guinea pig) showed that chromogranin A immunoreactivity and argyrophil stain partly overlap in identical endocrine cells, but do not necessarily coincide in the majority of endocrine cells. We found that endocrine cells could be positive for chromogranin A and argyrophilia (e.g., aminergic endocrine cells); or positive for chromogranin A but negative for argyrophilia (e.g., insulin cells of all species; somatostatin cells of cattle and pig); or negative for chromogranin A but positive for argyrophilia (e.g., glucagon cells of pig and guinea pig); or negative for chromogranin A and argyrophilia (e.g., somatostatin cells of man and guinea pig). Such heterogeneities of the staining pattern for chromogranin A and argyrophil silver reaction were also observed in individual endocrine cells of a given population (e.g., gastrin cells). Hence, although recent dot-blot tests have shown that chromogranin A is an argyrophilic substance, in tissue sections chromogranin A immunostaining and Grimelius' silver staining did not coincide in various endocrine cells, for unknown reasons. Therefore, it is recommended to use both chromogranin A immunohistochemistry and the classical Grimelius' silver stain to "mark" that vast majority of endocrine cells in tissue sections.
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PMID:Chromogranin A immunoreactivity and Grimelius' argyrophilia. A correlative study in mammalian endocrine cells. 134 63

The effects of tetragastrin on mucus glycoprotein (mucin) metabolism and mucosal protection in rat gastric mucosa were investigated. Rats were administered with various doses of tetragastrin (12, 120, or 400 micrograms/kg body weight; s.c.), followed by 50% ethanol-induced gastric injury. Tetragastrin caused a significant increase in mucin content in the corpus mucosa and prevented 50% ethanol-induced gastric mucosal damage in a dose-dependent manner. For assessment of the effects of tetragastrin on the metabolism of gastric mucin in detail, changes in mucin distribution in the three different layers of rat gastric mucosa were examined one hour after single administration of tetragastrin. A significant increase in the mucin content was noted in the mucus gel and surface mucosal layer. Mucin content in the deep mucosa corresponding mainly to the mucus neck cell mucin underwent virtually no change by this treatment. An increase in mucin in the mucus gel and surface mucosa would thus appear due to the administration of tetragastrin and may possibly be related to the protective action of the gastric mucosa against injury. The data demonstrate a possibility that gastrin may have potential for enhancing gastric mucosal protection associated with mucus secretion and/or mucus synthesis on the surface mucosa of rat gastric mucosa.
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PMID:Effects of tetragastrin on mucus glycoprotein in rat gastric mucosal protection. 138 48

Expression of the alpha-subunit of glycoprotein hormones is an acquired feature of the endocrine cells of the oxyntic mucosa in patients with sustained serum levels of gastrin, and may be related to the hyperplasia-carcinoid sequence occurring in these patients. In the present study we have investigated the intragastric cellular localization and the circulating levels of alpha-subunit in a patient with Zollinger-Ellison syndrome. In this patient we have found that: 1) Endocrine cells accounted for 2.29% +/- 1.44% of the total oxyntic mucosal volume (normal value: 0.9% +/- 0.4%), with the ECL cells representing 63.22% +/- 10.9% of the total endocrine cell volume (normal value: 29.8 +/- 8.8%). 2) Cells immunoreactive for the alpha-subunit were found to correspond ultrastructurally to a subpopulation of enterochromaffin-like cells, indistinguishable from similar cells devoid of significant immuno-electron microscopic labeling. 3) Immunoreactive cells included a portion of oxyntic endocrine cells with punctate granules, a feature previously observed only in carcinoid tumors of the oxyntic mucosa. 4) In consecutive sections of freeze-dried vapor-fixed biopsies a fraction of alpha-subunit storing cells was found to co-express histamine. 5) The serum alpha-subunit levels were abnormally elevated and paralleled those of gastrin in a secretin-stimulation test. Analysis of similar curves in two other patients with Zollinger-Ellison syndrome, and five patients with hypergastrinemic atrophic gastritis, all presenting alpha-subunit containing oxyntic endocrine cells, showed significant alpha-subunit elevations only in the patients with ulcerogenic syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Glycoprotein hormone alpha subunit in endocrine cells of human oxyntic mucosa. Studies on its relation to neuroendocrine tumors. 169 Jan 69

HPLC-purified 125I-labeled vasoactive intestinal peptide (VIP) bound in a specific, saturable, and reversible manner to pancreatic plasma membranes isolated from newborn calves, from milk-fed calves at 28 and 119 days, and from weaned calves at 119 days. A series of VIP analogues, including pituitary adenylate cyclase-activating polypeptide (PACAP), displaced 125I-VIP binding and activated adenylate cyclase in the same order of relative potency: PACAP-38 greater than helodermin greater than VIP, PACAP-27 greater than PHM (human peptide with NH2-terminal histidine and COOH-terminal methionine amide). At maximally effective concentrations, these five peptides produced the same two- to threefold increase of adenylate cyclase activity in pancreatic membranes from newborn and 28-day-old calves, and fourfold in ruminant or preruminant animals at 119 days. The activation constant for PACAP-38 ranged from 0.1 to 0.34 nM throughout the postnatal development. Helospectin I and II were three times less potent than VIP in inhibiting 125I-VIP binding. At concentrations up to 0.1 microM, secretin, rat and human growth hormone-releasing factors, glucagon, oxyntomodulin, the truncated form of glucagon-like peptide-1 lacking the 6 NH2-terminal amino acid sequence (TGLP-1), GLP-2, gastric inhibitory peptide, gastrin, CCK, and insulin had no effect on binding. Scatchard plots from 28- and 119-day-old calves were compatible with the presence of two classes of 125I-VIP binding sites: one with a high affinity for VIP and a low binding capacity (Kd = 0.11-0.4 nM, Bmax = 66-174 fmol/mg protein) and the other with a low affinity and high binding capacity. At birth, only one class of binding sites was observed (Kd = 0.4 nM, Bmax = 858 fmol/mg protein). The covalently cross-linked PACAP-preferring 125I-VIP binding site is a glycoprotein of 55 kDa with higher sensitivity to PACAP vs. helodermin and VIP. Our results suggest that calf pancreatic functions might be regulated at an early stage of postnatal development by PACAP receptors linked to cAMP generation.
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PMID:Characterization of binding sites for VIP-related peptides and activation of adenylate cyclase in developing pancreas. 184 91

1. A suspension of cells, containing about 30% mucous cells, was isolated from the rat fundic mucosa, and was pre-incubated with D-[6-3H]glucosamine. 3H-labelled material subsequently released into the medium was separated by Fast Protein Liquid Chromatography on a Superose 6 column. 2. A sharp peak of labelled high molecular weight material eluted from the column close to the void volume. This material was identified as mucous glycoprotein by its similar chromatographic behaviour to partially purified rat gastric mucous glycoprotein, by its resistance to complete degradation by papain and by its behaviour on treatment with dithiothreitol. On a caesium chloride density gradient the labelled material was virtually all located between densities of 1.35 and 1.53 g/ml. with the main peak at 1.40 g/ml. 3. A broad peak of lower molecular weight material was also eluted from the column. The release of this unidentified material did not seem to be closely associated with the release of mucous glycoprotein from the cells. 4. Release of mucous glycoprotein was stimulated by secretin (half-maximally effective concentration 2.3 nM, 84% stimulation above basal release at 100 nM), and by isoprenaline (half-maximally effective concentration 34 nM, 33% stimulation at 1 microM). Carbachol (0.5 nM) produced a significant (18-29%) stimulation of mucus secretion, but gastrin (100 nM), histamine (0.5 mM) and epidermal growth factor (200 nM) were without effect. 5. The preparation should prove useful in the identification of the agents which regulate gastric mucus secretion.
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PMID:Regulation of mucus secretion by cells isolated from the rat gastric mucosa. 238 55

Previous studies have shown that hyperplastic endocrine cells of the oxyntic mucosa in patients with atrophic gastritis may express immunoreactivity for the alpha-subunit of human chorionic gonadotropin (alpha-HCG, common to all glycoprotein hormones). Since this endocrine proliferation is regarded as dependent on the trophic effect of the concomitant hypergastrinemia, the relation between immunohistochemical expression of alpha-HCG by oxyntic endocrine cells and serum levels of gastrin were investigated. The study was performed on endoscopic gastric biopsies of the oxyntic mucosa from 49 patients subdivided into the following groups: A) with histologically normal mucosa and normogastrinemia (22 cases), B) with atrophic gastritis and normogastrinemia (12 cases), C) with normal mucosa and hypergastrinemia (Zollinger-Ellison syndrome, retained antrum) (7 cases) and D) with atrophic gastritis and hypergastrinemia (with or without pernicious anemia) (8 cases). The alpha-HCG immunoreactive cells were found in all hypergastrinemic patients (groups C and D), regardless of the concomitant pathological condition of the mucosa. These cells accounted for 7.8% to 44.7% of the number of Grimelius argyrophil cells in consecutive serial sections. In contrast, alpha-HCG-containing cells were exceptional or absent in most normogastrinemic patients. Their number was sizable in only two cases of group A and three cases of group B, where it ranged from 2.5% to 14.8% of the number of argyrophil cells. It was concluded that expression of alpha-HCG is another feature of oxyntic endocrine cells associated with hypergastrinemia in addition to those previously recognized such as development of hyperplasia and/or carcinoid tumors.
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PMID:Expression of glycoprotein hormone alpha-subunit by endocrine cells of the oxyntic mucosa is associated with hypergastrinemia. 245 43

The morphological and functional characteristics of the endocrine cells of the oxyntic (acid-secreting) mucosa of the human stomach, a target of the trophic effect of gastrin, are reviewed. In healthy subjects these cells account for 0.90 +/- 0.35% of the volume of the entire mucosa and for 1.21 +/- 0.44% of the volume of the epithelial mucosal component alone. The cells show no extension to the glandular lumen and show an intimate anatomic relationship with contiguous non-endocrine epithelial cells. This configuration indicates undefined local functions of the paracrine type not influenced by the gastric lumen content. Seven cell types were identified ultrastructurally, three of which (enterochromaffin-like (ECL), P and D) cumulatively account for more than 75% of the total endocrine cell mass. The secretory product(s) of the endocrine cells has not been demonstrated definitively with the exception of minor cell populations producing glucagon (only in the fetal life), somatostatin and 5-HT. Recently, production of histamine and glycoprotein hormone alpha-subunit by oxyntic endocrine cells of man have been reported. However, histamine seems to occur in these cells normally, whereas the production of glycoprotein hormone alpha-subunit appears to be virtually restricted to cells of patients with hypergastrinaemic conditions.
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PMID:Structure and function of endocrine cells in the oxyntic (acid-secreting) mucosa of human stomach. 269 Mar 28


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