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 vicinity of several hormone-producing glands as part of the anatomy of the intestinal tract and the resulting interaction has been confirmed by the discovery of hormonal factors of a specifically gastro-intestinal origin. Today we are mainly interested in the interaction between intermediary metabolism and incretory intestinal function; this is characterized by the joint action of conventional glandular hormones such as insulin and pancreatic glucagon as well as by the incretion of diffuse intestinal organs, hormones such as secretin, pancreozymin, motilin, VIP and GIP. The latter are at present subject of active research with the object of discovering their physiological significance be it as tissue hormones or as humoral agents with a "long distance" impact; their role within pathophysiology is also of interest. GIP ("gastric inhibitory peptide"), apart form acting upon the intestinal tract, also causes a marked rise in insulin production; this GIP possibly is the factor responsible for the difference in glucose tolerance following i. v. or oral administration of glucose, something that scientists have been trying to discover for a long time. We have also endeavored to investigate somatostatin. This substance was originally discovered as a hypothalamic factor with inhibitory action on growth hormone secretion; in the meantime, however, cells containing and possibly also producing somatostatin have also been detected in the intestine and particularly in the islets of Langerhans (D-cells). Since somatostatin inhibits insulin secretion and especially glucagon release as well as the exretory functions of the stomach and of the pancreas, the significance of this hormone possibly is that of a tissue hormone with inhibitory action on adjacent cells. As factor inhibiting both endocrine and exocrine secretory processes it would combine these two complexes. The possible therapeutic significance of somatostatin administration to diabetics would lie in the saving of insulin. A third sector of present-day research deals with the interaction between the calcium metabolism and the hormones involved as well as the intestine. We know that patients suffering from primary hyperparathyroidism are prone to contract stomach ulcers and pancreatitis; patients with a gastrinoma and a hyperfunction of the epithelial bodies suffer from a Zollinger-Ellison-sindrome and this again suggests association with endocrine polyadenomatosis (Wermer syndrome). The inhibitory action of the parathormone antagonist calcitonin on the exocrine functions of the intestinal tract, such as the acid secretion of the stomach and the enzyme secretion of the pancreas, have already given rise to some considerations and experiments relative to treatment. It is to be hoped that because of all the joint observations cited above there will be better intergration of research both from the aspect of gastro-enterology and endocrinology. This might hopefully elucidate some of the unresolved problems ranging from basic research to practical application.
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PMID:[Interaction between gastrointestinal hormones and endocrine regulation]. 0 83

Reliable and specific radioimmunoassays have been developed for the gut hormones secretin, gastrin, cholecystokinin, pancreatic glucagon, VIP, GIP, motilin, and enteroglucagon. Using these assays, the relative pattern of distribution of the gut hormones has been determined using the same bowel extracts for all measurements. VIP occurred in high concentration in all regions of the bowel, whereas secretin, GIP, motilin, and CCK were predominantly localised in the proximal small intestine. Pancreatic glucagon was almost exclusively confined to the pancreas. Like VIP, enteroglucagon also exhibited a wide pattern of distribution but was maximal in the ileum. The acid ethanol extraction method that was used was found to be unsuitable for gastrin. On gel chromatography of the extracts, motilin and VIP eluted as single molecular species in identical position to the pure porcine peptides. CCK, pancreatic glucagon, enteroglucagon and GIP were all multiform.
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PMID:Distribution of the gut hormones in the primate intestinal tract. 11 57

Increased gastric acid secretion occurs after extensive intestinal resection in man, dog, rat, and monkey. Hypergastrinemia has been observed in patients with short gut syndrome and appears to accompany the hyperacidity after intestinal resection in dog, rat, and monkey. Postresectional hypergastrinemia is caused by increased release of gastrin and/or decreased degradation of the hormone. Other hormonal changes after extensive resection include increased insulin, GIP, pancreatic glucagon, and decreased enteroglucagon.
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PMID:Hyperacidity and hypergastrinemia following extensive intestinal resection. 11 43

Gastro-entero-pancreatic (GEP) and bronchial endocrine tumours have been studied by immunohistochemistry using specific antisera against a variety of hormonal and neuronal peptides. In gastrinomas numerous tumour cells were found to contain GH-like immunoreactivity. These cells were identical with those storing gastrin. Gastrinomas as a rule were extremely heterogeneous containing a variety of minority cell populations, including CCK immunoreactive cells and neurotensin immunoreactive cells. Glucagonoma cells were found to store GIP-like material in addition to glucagon. In some insulinomas calcitonin-like material was encountered in the insulin producing tumour cells. In both glucagonomas and insulinomas other pancreatic endocrine cell types constituted minority cell populations. One intestinal somatostatinoma contained gastrin cells as a minority cell population. Bronchial endocrine tumours contained scattered cells displaying ACTH-like or enkephalin-like immunoreactivity. Two such tumours in addition contained cells displaying neurophysin immunoreactivity.
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PMID:Majority and minority cell populations in GEP and bronchial endocrine tumours. 22 92

By means of a statistical analysis of the occurrence of amino-acid residues in the polypeptide chains of several gastro-entero-pancreatic (GEP) hormones an investigation was undertaken to determine whether any of these hormones might be related to each other--possibly from an evolutionary point of view. Particular interest was paid to the occurrence of small charged segments, i.e. those with acidic or basic amino acid residues, since such segments can be presumed to play a role in hormonal receptor binding mechanisms. By this method hormonal relationships were suggested by the observation that these small charged amino-acid sequences, contained in the hormonal structures, match as a result of non-randomness. It was found that hagfish and human insulin were related on a molecular level not only to the newly discovered (avian, bovine, human) pancreatic polypeptide (PP) but also to some other GEP hormones (VIP, GIP, glucagon) as well as to calcitonin and to the alpha-subunit of the glycoprotein hormones. Interpretation of the statistical data suggests that all these peptide hormones are related by a common hexapeptide sequence which contributed, at an evolutionary point, to their molecular architecture. A hexapeptide segment of APP is statistically related to a sequence of equal size in the carboxy terminal region of the A-chain of both hagfish and human insulin, providing the first instance of their structural similarity. Correlations between PP, insulin, glucagon, VIP, and calcitonin provide a tentative basis for predicting the production of one or more of these peptide hormones by immature or de-differentiated cells of neoplasms and non-neoplastic pathologic lesions of the GEP endocrine system.
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PMID:Structural analysis of the molecular evolution of some gastro-entero-pancreatic hormones. 27 67

In rat pancreatic islets, the glucagon-producing A-cells also contain a GIP-like material as revealed by the peroxidase-antiperoxidase immunocytochemical technique. Control studies showed that this dual staining was not due to the cross-reactivity of anti-GIP with glucagon. It is concluded either that the A-cells synthesize a GIP-like peptide or that it is taken up from the circulation.
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PMID:Immunocytochemical localization of a gastric imhibitory polypeptide-like material within A-cells of the endocrine pancreas. 33 96

Responses of plasma immunoreactive gastric inhibitory polypeptide (IRGIP) to oral triglyceride or galactose were compared in normal and mildly diabetic (non-insulin-dependent) subjects. After triglyceride the responses of IRGIP were similar, but after galactose those of the diabetics were slightly exaggerated. Both stimuli evoked increments of plasma immunoreactive glucagon (IRG) in diabetics but not in normal subjects. Plasma immunoreactive insulin (IRI) did not change. In normal subjects given oral triglyceride or galactose followed by intravenous (I.V.) glucose the early-phase response of plasma IRI was enhanced and glucose tolerance improved. In the diabetics, oral triglyceride did not affect insulin release or glucose tolerance after I.V. glucose; oral galactose elicited a slight increase of insulin release without improving glucose tolerance. In the diabetics the rise of plasma IRG after ingestion of triglyceride or galactose was maintained after I.V. glucose. It is concluded that endogenous GIP is insulinotropic and that there is partial resistance to this action in diabetes. The results were compatible with feedback inhibition of GIP secretion by insulin and with the suggestion that the rise of plasma IRG associated with secretion of GIP in diabetics may be due to the glucagonotropic action of this peptide.
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PMID:Effects of ingestion of triglyceride or galactose on secretion of gastric inhibitory polypeptide and on responses to intravenous glucose in normal and diabetic subjects. 64 Feb 38

The effect of intravenous glucagon infusion on serum levels of immunoreactive GIP (IR-GIP), insulin (IRI), gastrin (IRG), and on blood glucose has been investigated in six healthy volunteers in the fasting state and during ingestion of a mixed standard meal. Glucagon (500 ng/kg/min) lowered significantly serum levels of IR-GIP and IRG below the fasting values and increased the levels of IRI and blood glucose. Glucagon (50 ng/kg/min) infused 30 minutes before and continued 90 minutes after ingestion of a test meal abolished the IR-GIP response, suppressed significantly the IRG response, and left the IRI response unchanged. The same glucagon dose infused 60 minutes after ingestion of the test meal decreased significantly the raised levels of IR-GIP and IRG to fasting levels without changing IRI values. It is concluded that exogenous glucagon inhibits Gip release at the level of the GIP-producing cells.
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PMID:Lowering of fasting and food stimulated serum immunoreactive gastric inhibitory polypeptide (GIP) by glucagon. 85 72

Five dogs prepared with Heidenhain pouches received infusions of saline, GIP and VIP before and after a standard meat meal. Blood samples were obtained under basal conditions and at subsequent intervals for measurement of gastrin, insulin, GIP and VIP by radioimmunoassay. GIP and VIP infusions had no effect on basal levels of gastrin. GIP and VIP (in common with secretin and glucagon) were found to suppress food-stimulated release of gastrin and gastrin-stimulated acid secretion from the Heidenhain pouch. Insulin levels were significantly elevated during GIP and VIP infusions. Food released GIP (and perhaps VIP.
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PMID:Suppression of gastrin release and gastric secretion by gastric inhibitory polypeptide (GIP) and vasoactive intestinal polypeptide (VIP). 93 20

Gastrointestinal hormones are considered to be those that are formed in the gastrointestinal tract and there, in physiological concentrations, develop their effects on motility, secretion, trophism, bloodflow and absorption. Structural analysis, synthesis or a high degree of purity after extraction, and its exact demonstration by means of a useful radioimmunoassay, form the basis for the establishment of a polypeptide as a gastrointestinal hormone. To this category belong, at the present time, gastrin, cholecystokinin-pancreozymin (CCK-PZ) and secretin. GIP, VIP, motilin, glucagon and somatostatin are considered likely candidates. The substances gastrin and CCK-PZ, which are structurally related and have a predominantly stimulating effect, and the structurally dissimilar motilin, contrast with the partially or totally inhibiting hormones of the glucagon family, namely, secretin, VIP, glucagon-enteroglucagon, GIP and somatostatin. By the combined action of these hormones with one another and with the autonomic nervous system, the digestive processes are regulated. Disturbances in the formation of these hormones, in particular an overproduction, give rise to disease syndromes that can now be diagnosed and, in part, treated by surgery. The therapeutic application of gastrointestinal hormones has now also become a possibility.
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PMID:[Gastrointestinal hormones]. 96 Sep 54


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