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)

5-hydroxytryptophan (5HTP), the immediate precursor of serotonin, induces a release of insulin and glucagon in the intact rat. These effects of 5HTP, which have previously been shown to be blocked by L-aromatic amino acid decarboxylase inhibition, were also prevented by methysergide (a serotonin receptor antagonist). Quipazine (a serotonin receptor agonist) did not alter pancreatic hormone release. Fluoxetine, a serotonin neuronal reuptake blocker did not effect insulin secretion and had a slight glucagon stimulatory effect, however the effects of 5HTP on insulin and glucagon release were not potentiated by fluoxetine pretreatment. Alpha and beta-adrenergic receptor blockade did not alter the pancreatic effects of 5HTP.
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PMID:The acute effects of 5HTP, fluoxetine and quipazine on insulin and glucagon release in the intact rat. 31 41

The identity of monoamine-emitted, formaldehyde-induced fluorescence in some pancreatic islet cells was studied in pancreatic tissue of male chickens by fluorescence and immunohistochemistry either on the same tissue section or on serial tissue sections. Pancreatic islet cells emitting intense formaldehyde-induced fluorescence also react immunohistochemically with antisera directed against glucagon, serotonin and aromatic L-amino acid decarboxylase. These results show that chicken pancreatic islet A cells contain glucagon, serotonin, and aromatic L-amino acid decarboxylase, an enzyme involved in the synthesis of serotonin. The islet B cells identified with anti-insulin immunoreactivity, which displayed a very weak formaldehyde-induced fluorescence, did not react with anti-serotonin serum.
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PMID:Immunohistochemical colocalization of glucagon, serotonin, and aromatic L-amino acid decarboxylase in islet A cells of chicken pancreas. 240 8

In embryonic mice, the catecholamine biosynthetic enzyme tyrosine hydroxylase [L-tyrosine, tetrahydropteridine:oxygen oxidoreductase (3-hydroxylating), EC 1.14.16.2] can be visualized immunocytochemically in a population of cells in epithelial cords of the developing pancreas. These embryonic catecholamine cells, first seen by day 11, are large and vacuolated and have a folded nuclear membrane. One day later, at day 12, glucagon is first detected immunocytochemically in pancreatic cells similar in location and morphology to the embryonic catecholamine cells. By use of a method for detecting both antigens in the same cell, both the hydroxylase and glucagon can be visualized between day 12 and day 14 in 10-40% of stained cells. From day 14, the number of cells stained for hydroxylase decreases; they cannot be detected after day 18. In contrast, the cells containing glucagon increase during development and persist throughout life. Endocrine cells of the embryonic pancreas also contain dopa decarboxylase but not dopamine-beta-hydroxylase or phenylethanolamine-N-methyl transferase. In adult mice, small cells containing tyrosine hydroxylase but differing in location and morphology from the embryonic catecholaminergic cells are seen in pancreatic islets. The adult catecholaminergic cells never store glucagon. We suggest that adult glucagon (A)-containing cells arise from transformation in situ of cells that transiently express a catecholaminergic (probably dopaminergic) phenotype. These results suggest that one class of peptidergic cells may arise from transformation of an aminergic precursor.
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PMID:Transformation of catecholaminergic precursors into glucagon (A) cells in mouse embryonic pancreas. 611 53

A population of cells containing the enzymes tyrosine hydroxylase (TH) and dopa-decarboxylase (L-AADC) but not dopamine-B-hydroxylase (DBH) nor phenylethanolamine-N-methyltransferase (PNMT) can be detected with immunocytochemical techniques in the pancreas of mouse embryos at the 11th day of development (E 11). The presence of TH in embryonal pancreas is transient: TH is not observed after E 15. By use of a method for simultaneously detecting two antigens in the same section both TH and glucagon were visualized in the same cell on E 12. Double labelled cells comprised 10% of all stained cells. At E 14.5, some of the cells stained for TH also contained insulin. However, at the time somatostatin appeared no embryonal cells containing TH remained. We conclude that two cell types of the APUD series, i.e., the glucagon and insulin cells of pancreas, arise from transformation, in situ, of cells that transiently express a dopaminergic phenotype. These results suggest that peptide-containing cells in skin, brain and gut are linked by a common embryonic origin. They also raise the prospect that other peptidergic cells of the APUD series may have aminergic precursors.
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PMID:Linkage of the brain-skin-gut axis: islet cells originate from dopaminergic precursors. 612 86

The colocalization of serotonin and aromatic L-amino acid decarboxylase (AADC) in the avian pancreatic polypeptide-containing PP-cells and glucagon-storing A-cells of the chicken endocrine pancreas was investigated using combined pre-embedding immuno-peroxidase and post-embedding immunogold electron microscopic immunocytochemistry. The avian pancreatic polypeptide-immunoreactive cells manifested by the labeling of immunogold particles on secretory granules were also immunoreactive with antisera directed against serotonin and AADC, an enzyme involved in the synthesis of serotonin. In PP-cells immunoreactivity against the anti-serotonin serum was stronger in secretory granules than in the cytoplasmic matrix, whereas immunoreaction with the anti-AADC serum was observed to be more intense in the cytoplasmic matrix. Immunoreactions with the serotonin and AADC antisera were also found in secretory granules of glucagon-storing A-cells. These results indicate that serotonin is co-stored within secretory granules of both A- and PP-cells, and that AADC is localized within secretory granules of A-cells, and may be present in the cytoplasmic matrix of PP-cells. It is probable that serotonin is synthesized and released simultaneously with secretory granules from both A- and PP-cells of the chicken endocrine pancreas.
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PMID:Immunocytochemical colocalizations of serotonin, aromatic L-amino acid decarboxylase and polypeptide hormones in A- and PP-cells of the chicken endocrine pancreas. 757 May 78

To establish which monoamines are elaborated in the pancreatic islet cells of cats, the pancreatic tissue was studied by immunohistochemistry on serial or mirror tissue sections. Glucagon-containing A-cells reacted immunohistochemically with antisera directed against serotonin and aromatic L-amino acid decarboxylase, though the half of A-cells immunostained with glucagon antiserum did not show the colocalization with serotonin. Pancreatic polypeptide-containing PP-cells also showed immunoreactivity for antisera directed against serotonin and aromatic L-amino acid decarboxylase. However, PP-cells exhibiting immunoreactivity for serotonin were very few in number. The overlapping areas of the two types of cell represented only a small proportion of the PP-cells. Immunoreactivity for aromatic L-amino acid decarboxylase was observed within almost all A- and PP-cells. Since aromatic L-amino acid decarboxylase is an enzyme involved in the synthesis of serotonin, it is concluded that pancreatic islet A- and PP-cells in cats have the ability to elaborate serotonin. Contrarily, islet B- and D-cells showing immunoreactivity for insulin and somatostatin antisera, respectively, did not react with antisera directed against serotonin and aromatic L-amino acid decarboxylase.
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PMID:Immunohistochemical colocalization of serotonin, aromatic L-amino acid decarboxylase and polypeptide hormones in islet A- and PP-cells of the cat pancreas. 786 93

The aim of this work was to investigate the possible presence of DOPA decarboxylase (DDC) in endocrine cells of adult rat pancreas. Islet peptide hormones (insulin, glucagon, and somatostatin), as well as DDC, were detected immunohistochemically using the double-immunofluorescence technique and specific antibodies. DDC-like immunoreactivity was present in cytoplasmic granules within endocrine cells located at islet peripheries in a distribution consistent with islet localisation of A cells. Moreover, these same cells stained positively with glucagon antibody. As DDC is an enzyme specifically involved in catecholamine synthesis, insular cells must possess the capacity to elaborate this class of hormone at least up to the dopamine-decarboxylation step. Thus, after further metabolic processing either in A cells or elsewhere, endogenously-synthesised islet catecholamines may be released and participate in paracrine regulation of insulin secretion.
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PMID:Presence of DOPA decarboxylase and its localisation in adult rat pancreatic islet cells. 913 6