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)

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 chromogranins are soluble, acidic, proteins which are frequently co-stored in neuroendocrine cells with biogenic amines. In the gastric mucosa chromogranin A is localized to enterochromaffin-like cells which are the main source of histamine, and which are known to be regulated by circulating gastrin. We have used radioimmunoassays selective for the extreme C-terminal regions of chromogranin A and B to examine changes in gastric extracts following modulation of the gastric luminal contents. There were decreased concentrations of the two chromogranins in tissue extracts of rats after food withdrawal (which lowered plasma gastrin concentrations); inhibition of acid secretion with the H+/K(+)-ATPase inhibitor, omeprazole (which increased plasma gastrin concentrations) raised chromogranin A and B concentrations both in fasted rats, and in rats fed ad libitum. There was no evidence for altered patterns of posttranslational cleavage of chromogranin A or B with these treatments. The data indicate that chromogranin A and B concentrations in gastric ECL cells are regulated in parallel with histamine production, and are consistent with the idea that the chromogranins play a role in the formation and stabilization of the secretory granule involved in amine storage.
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PMID:Functional control of chromogranin A and B concentrations in the body of the rat stomach. 143 76

Atypical carcinoid tumor of the lung with amyloid stroma seen in a 43-year-old woman is reported. The 47 x 45 x 33 mm tumor, located at the periphery of the S8 segment of the resected left lower lobe, revealed Dylon-positive amyloid deposition in the stroma. The argyrophilic tumor cells with occasional mitoses and focal venous involvement predominantly showed immunoreactivity of cytokeratin, neuron-specific enolase, cystatin C, chromogranin A, calcitonin and neuropeptide Y (NPY). Fewer cells were immunoreactive for calcitonin gene-related peptide (CGRP), the alpha-subunit of human chorionic gonadotropin, gastrin-releasing peptide, serotonin, methionine-enkephalin and gastrin. Immunoreactive CGRP or NPY were co-localized in calcitonin-positive cells. The amyloid substance was positively labeled only for CGRP. Immunostaining for amylin, a polypeptide isolated from insular amyloid in type II diabetes mellitus or insulinoma showing a 50% homology with CGRP, was negative. The specificity of immunostaining for calcitonin, CGRP and amylin was confirmed by immunoabsorption tests using synthetic human antigens. Immunoelectron microscopic studies disclosed peptide localization in neurosecretory-type granules and CGRP immunoreactivity in extracellular amyloid fibrils. This is the first report describing CGRP as a component of amyloid of endocrine origin.
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PMID:Atypical carcinoid tumor of the lung with amyloid stroma. 160 16

Endocrine cells in the gastrointestinal tract of the domestic duck were identified immunocytochemically using antisera specific to bombesin, chromogranin A, cholecystokinin (CCK), gastrin, glucagon, neuron specific enolase (NSE), neurotensin, secretin, 5-hydroxytryptamine (5-HT), somatostatin, substance P and vasoactive intestinal polypeptide (VIP). Chromogranin A, 5-HT and somatostatin immunoreactive cells were widespread throughout the gastrointestinal tract. Bombesin immunoreactive cells were observed only in the proventriculus and the gizzard. CCK, substance P and neurotensin immunoreactive cells were present in the intestinal tracts from the duodenum to the colorectum. The latter were numerous also in the antrum. Gastrin cells were peculiar to the antrum but present also in the gizzard and small intestine. Glucagon immunoreactive cells were present in the jejunum-ileum and above all in the large intestine. Only few secretin cells were present in the duodenum. The highest frequency of endocrine cells was found in the antrum, while the lowest was observed in the caeca. Antisera to somatostatin and substance P showed numerous nerve cells and fibers besides endocrine cells, whereas NSE and VIP immunopositivity was found in the nervous structures only of the gut wall.
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PMID:An immunohistochemical study on the endocrine cells in the gastrointestinal tract of domestic duck. 168 96

Immunohistochemical studies of the gastrointestinal tract were carried out to characterize the cells exhibiting immunoreactivity for chromogranin A (CGA), a glycosylated protein primarily found in secretory granules of the adrenal medulla. Double immunostaining for gastrointestinal hormones and CGA revealed that in the bovine gastrointestinal tract CGA immunoreactivity occurs in mucosal epithelial cells containing gastrin, glucagon, substance P or motilin, but not in those containing somatostatin. Combined staining with anti-CGA serum and Grimelius' silver demonstrated frequent association of the two stains in a variety of endocrine cells. However, intracellular distribution of the two stains was different: CGA-immunoreactivity was detected in both supra- and infranuclear cytoplasm, whereas Grimelius' silver was mostly localized in the infranuclear region. These results suggest that CGA is the target of Grimelius' silver, as postulated recently (Rindi et al., 1986), but that some subcellular structure-related modification of molecules such as sialation is necessary for the positive Grimelius reaction.
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PMID:Localization of chromogranin A-immunoreactivity in bovine gastrointestinal endocrine cells with special reference to Grimelius silver stain. 169 53

A case of neuroendocrine lung tumor located beneath the pleura in a 71-year-old woman is reported. At autopsy, the tumor was found to have metastasized to the bones and liver without involving the hilar lymph nodes. Histologically, the tumor cells at the primary site and in the liver metastasis exhibited a carcinoid-like organoid structure, whereas pleomorphic giant cells were noted in the bone metastasis. The argyrophilic tumor cells were immunoreactive for neuron-specific enolase, chromogranin A, serotonin, calcitonin, calcitonin gene-related peptide, gastrin-releasing peptide, neuropeptide Y, gastrin, pancreatic polypeptide, glicentin, the alpha-subunit of human chorionic gonadotropin, keratin, epithelial membrane antigen, Leu M1 and carcinoembryonic antigen. Electron microscopy revealed abundant neurosecretory granules in the cytoplasm. This was considered to be a rare case of neuroendocrine lung tumor showing carcinoid-like histology at the primary site and large-cell transformation in bone metastasis.
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PMID:Atypical carcinoid tumor of the lung, associated with giant-cell transformation in bone metastasis. 170 May 76

A histologic and immunohistochemical study was carried out in 23 unselected nonantral gastric carcinoids and their precursor lesions classified according to Solcia et al. None of the patients showed Zollinger-Ellison syndrome. Two variants of carcinoids showing distinctive pathologic and pathogenetic characteristics were identified on the basis of presence or absence of associated chronic atrophic gastritis type A (A-CAG). Chronic atrophic gastritis type A was found in 19 cases showing either single or multiple neoplasms, tumor extension limited to the mucosa or submucosa, consistent endocrine cell precursor changes in extratumoral mucosa, and consistent hypergastrinemia and/or G cell hyperplasia. Associated precursor lesions were only hyperplastic in all but two cases with single carcinoids whereas they were also dysplastic in all but one case with multiple carcinoids. The four tumors arising in nonatrophic mucosa were all single, more aggressive, and not associated with extratumoral endocrine cell proliferations or with signs of gastrin hypersecretion. Tumor cells were diffusely immunoreactive for chromogranin A and synaptophysin but usually negative for chromogranin B or HISL-19. Scattered serotonin cells were found in ten carcinoids. They were more frequent in infiltrating than in intramucosal tumors as were the less represented pancreatic polypeptide cells whereas the reverse was found for alpha-subunit-containing cells. These results are of relevance for tumor pathogenesis and may provide the rationale for a less aggressive therapeutic approach in the patients.
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PMID:Gastric carcinoids and their precursor lesions. A histologic and immunohistochemical study of 23 cases. 170 55

The authors have established a long-term tissue culture cell line (BON) derived from a metastatic human carcinoid tumor of the pancreas. The cells have been in continuous passage for 46 months. Tissue culture cells produce tumors in a dose-dependent fashion after SC inoculation of cell suspensions in athymic nude mice. BON tumors, grown in nude mice, are histologically identical to the original tumor; they possess gastrin and somatostatin receptors, synthesize serotonin and chromogranin A, and have a doubling time of approximately 13 days. The antiproliferative effects of the long-acting somatostatin analogue, SMS 201-995 (300 micrograms/kg, t.i.d.), and 2% alpha-difluoromethylornithine on BON xenografts in nude mice were examined. Tumor size was significantly decreased by day 14 of treatment with either agent and at all points of analysis thereafter until the animals were killed (day 33). In addition, tumor weight, DNA, RNA, and protein contents were significantly decreased in treated mice compared with controls. Establishment of this human carcinoid xenograft line, BON, provides an excellent model to study further the biological behavior of carcinoid tumors and the in vivo effect of chemotherapeutic agents on tumor growth.
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PMID:Establishment and characterization of a human carcinoid in nude mice and effect of various agents on tumor growth. 171 29

Chromogranins A and B are glycoproteins originally detected in the adrenal medulla. These proteins are also present in a variety of neuroendocrine cells. The subcellular distribution of the chromogranins, and particularly their intra-granular topology are of special interest with respect to their putative functions. Endocrine cells of the guinea pig adrenal medulla, pancreas and gastric mucosa were investigated immunoelectron microscopically for the subcellular distribution of both chromogranins. Out of 13 established endocrine cell types in all locations, only two endocrine cell types showed immunoreactivity for both chromogranin A and B, and eight endocrine cell types showed immunoreactivities only for chromogranin A. These immunoreactivities varied inter-cellularly. Three endocrine cell types were unreactive for the chromogranins. Moreover, some hormonally non-identified endocrine cells in the pancreas and the gastric mucosa also contained chromogranin A immunoreactivities. Subcellularly, chromogranin A or B were confined to secretory granules. In most endocrine cells, the secretory granules showed chromogranin immunoreactivities of varying densities. Furthermore, the intra-granular topology of chromogranin A or B in the secretory granules varied considerably: in some endocrine cell types, i.e. chromaffin-, gastrin- and enterochromaffin-like-cells, chromogranin A immunoreactivity was localized in the perigranular and/or dense core region of the secretory granules; in others, i.e. insulin-, pancreatic polypeptide- and bovine adrenal medulla dodecapeptide-cells, it was present preferentially in the electron-opaque centre of the secretory granules; chromogranin B immunoreactivity was localized preferentially in the perigranular region of the secretory granules of chromaffin cells and gastrin-cells. The inter-cellular and inter-granular variations of chromogranin A and B immunoreactivities point to differences in biosynthesis or processing of the chromogranins among endocrine cells and their secretory granules.
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PMID:Topology of chromogranins in secretory granules of endocrine cells. 172 76

A large cystic tumor in the pancreatic body was found incidentally in an 85-yr-old male. A distal pancreatectomy was performed after a diagnosis of cystadenocarcinoma. Microscopic examination of the resected specimen revealed a pancreatic cystic endocrine tumor; however, this tumor produced no symptoms. Immunohistochemical studies of the tumor cells showed positivity for gastrin, neuron-specific enolase, chromogranin A, and synaptophysin, and two cell types of neurosecretory granules were recognized in electron-microscopic studies. Although endocrine tumors of the pancreas are usually solid and cystic change occurs only rarely, such tumors should be considered in the differential diagnosis of patients who have a cystic lesion in the pancreas.
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PMID:Cystic endocrine tumor of the pancreas. 175 31


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