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

In the presence of 5 mM theophylline, secretin and vasoactive intestinal peptide (VIP) each increased cyclic adenosine 3':5'-monophosphate (cyclic AMP) in acinar cells isolated from guinea pig pancreas. Without theophylline, neither peptide altered cellular cyclic AMP. Glucagon, which is similar to secretin and VIP both in chemical structure and spectrum of biologic activities, neither stimulated cellular cyclic AMP nor inhibited the stimulation produced by secretin or by VIP. Other agents which were tested and found not to increase cellular cyclic AMP were cholecystokinin, carboxyl-terminal octapeptide of cholecystokinin, gastrin I, gastrin II, bovine pancreatic polypeptide, carbamylcholine, and prostaglandin E1. Neither carboxyl-terminal octapeptide nor gastrin I altered the stimulation of cellular cyclic AMP produced by secretin or VIP. With natural secretin a significant increase in cellular cyclic AMP could be detected at concentrations as low as 3 x 10(-10) M and maximal stimulation occurred at 10(-8) M. VIP was approximately 1% as potent as natural secretin and maximal concentrations of secretin plus VIP increased cellular cyclic AMP to the same value as was obtained with a maximal concentration of secretin alone.
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PMID:Cyclic AMP in pancreatic acinar cells: effects of gastrointestinal hormones. 17 15

Secretin and vasoactive intestinal peptide (VIP), but not glucagon, stimulate accumulation of cyclic AMP in dispersed guinea pig pancreatic acinar cells. Secretin stimulated cellular accumulation of cyclic AMP by interacting with a single class of high affinity receptors. On the other hand, the dose-response curve for VIP-stimulated cellular cyclic AMP was biphasic and reflected interaction of this peptide with two classes of receptors. Results obtained with synthetic fragments of VIP and secretin indicate that the receptor having a high affinity for VIP has a low affinity for secretin, interacts with, but does not distinguish among, secretin, secretin 5-27 and [6-tyrosine] secretin or among secretin 14-27, VIP 14-28, VIP 15-28, and increases cellular cyclic AMP when occupied by VIP, but not when occupied by secretin, [6-tyrosine] secretin, or secretin 1-14. The receptor having a low affinity for VIP has a high affinity for secretin, interacts with and distinguishes among secretin, secretin 5-27, and [6-tyrosine] secretin, interacts with secretin 14-27 but not with VIP 14-28 or VIP 15-28, and increases cellular cyclic AMP when occupied by VIP, secretin, [6-tyrosine] secretin, or secretin 1-14.
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PMID:Interaction of porcine vasoactive intestinal peptide with dispersed pancreatic acinar cells from the guinea pig. Structural requirements for effects of vasoactive intestinal peptide and secretin on cellular adenosine 3':5'-monophosphate. 18 79

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

In vivo, vasoactive intestinal peptide (VIP) produces simultaneous increases in blood glucose and insulin levels. In order to determine whether VIP, like its homologues, also stimulates insulin secretion directly, studies were made in controlled glucose media employing the vascularly perfused cat pancreas. VIP stimulated insulin secretion significantly in the presence of constant physiological concentrations of glucose. The highest insulin response to VIP (100.3+/-8.1 muU/min) approached the highest insulin response to glucose (119.9 +/- 12.0 muU/min). In the absence of glucose, the insulin response to VIP was insignificant. Unexpectedly, VIP was found to be a more effective stimulant of glucagon than of insulin secretion. The highest glucagon response to VIP (327+/-51% of control levels) was attained in the presence of physiological concentrations of glucose and equalled the glucagon response obtained upon withdrawal of glucose from the perfusate. The glucagon response to VIP was blocked by increasing the glucose in the perfusate. These studies indicate the VIP present in pancreatic islets might play a role in the local control of pancreatic endocrine function.
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PMID:Stimulation of insulin and glucagon secretion by vasoactive intestinal peptide. 32 Aug 78

Using immunohistochemical techniques we studied duodenal biopsies from 18 patients with coeliac disease and 24 patients with normal duodenal morphology. We had access to antisera against the following gastrointestinal peptides: cholecystokinin (CCK), gastric inhibitory peptide (GIP), gastrin-17, glucagon-enteroglucagon, motilin, neurotensin, pancreatic peptide (PP), secretin, somatostatin, substance P and vasoactive intestinal peptide (VIP). The somatostatin, GIP, CCK, and glucagon cells were increased in number in coeliac disease. The number of motilin cells was slightly increased, while secretin cells were reduced. Cells storing gastrin-17, substance P, or neurotensin were rare in all patients regardless of diagnosis. No PP immunoreactive cells were found and VIP was localised to neurons only. In biopsies from patients having a mucosa with ridging of villi the number of the various endocrine cell types did not differ from that in the control group.
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PMID:Duodenal endocrine cells in adult coeliac disease. 38 55

A method is described for perifusion of the splenic part of the pancreas from 48-64 hour-old rat. In different basal conditions, the secretion of insulin and glucagon is stable and reproducible for 90 mn. The addition of the vasoactive intestinal peptide (VIP) to these perifusion media, at a concentration as low as 2 ng/ml, determines a remarkable increase of insulin and of glucagon secretion. These results suggest the possibility of a VIP action in the physiology of endocrine pancreas.
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PMID:[Secretion of insulin and of glucagon by the perfused pancreas of newborn rats: effect of vasoactive intestinal peptide Vip]. 40 70

The release of pancreatic polypeptide (PP) by gut hormones, acetyl choline and adrenaline was investigated in an isolated perfused pancreas preparation. PP was potently released by 1 nmol/1 caerulein (186 +/- 12%, p is less than 0.001) and gastric inhibitory peptide (GIP) (211 +/- 31%, p is less than 0.005) as well as by 1 mumol/1 acetyl choline (1097 +/- 59%, p is less than 0.001). A significant two-fold release of PP was also evoked by 1 nmol/1 vasoactive intestinal peptide (VIP) (129 +/- 38%, p is less than 0.02 and gastrin (108 +/- 25% p is less than 0.01). Insulin release, induced by high glucose concentration was enhanced by both GIP (210 +/- 38%, p is less than (0.01) and VIP (48 +/- 5%, p is less than 0.001). In addition GIP enhanced the release of glucagon by 179 +/- 18% (p is less 0.001) at 1.4 mmol/1 glucose and by 127 +/- 24% (p is less than 0.005) at 8.3 mmol/1 glucose. Thus no simple inter-relationship appears to exist between the control of the three circulating islet hormones.
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PMID:Pancreatic polypeptide, glucagon and insulin secretion from the isolated perfused canine pancreas. 66 4

Fasting levels of 5 gut hormones were studied in 30 patients with advanced uraemia (CRF), 40 undergoing regular dialysis (RD) and 555 renal transplant patients (RT). Mean values of gastrin and total glucagon were markedly elevated in CRF and RD patients compared with 20 normal subjects; there were lesser elevations in pancreatic glucagon, insulin and vasoactive intestinal peptide (VIP). Secretin levels were unchanged. In RT patients, fasting levels of VIP and pancreatic glucagon had returned to normal, while levels of gastrin, total glucagon and insulin remained slightly elevated compared with controls. Food stimulated hormone levels were measured in 18 RD patients and compared with 18 controls. After eating, RD patients failed to show the late increase in total glucagon, or the suppression of VIP and secretin seen in normal subjects; the pattern of gastrin and insulin response was similar to controls, but after the initial increase plasma levels in RD patients tended to show a slower decline. Thus involvement of the gastrointestinal tract in uraemia is associated with functional disturbance of the endocrine system of the gut.
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PMID:Elevations of gastrointestinal hormones in chronic renal failure. 74 Jun 78

In addition to established gastrointestinal hormones--secretin, cholecystokinin-pancreozymin (CCK-PZ), gastrin, and glucagon---some 30 polypeptides with gastrointestinal actions can be listed. New aspects of these substances include the following: Gastrin and vasoactive intestinal peptide (VIP) can be also encountered in the central nervous system and may act as transmitters. CCK-PZ-serum concentrations are found markedly elevated in patients with exocrine pancreatic insufficiency; this may provide the opportunity to establish a realtively simple screening test. Moreover, there is evidence that serum-CCK-PZ levels serve as satiety signal. Secretin secretion is said to be enhanced in hunger and then to act as a lipolytic hormone. In addition to enteroglucagon, a gastrintestinal peptide identical to pancreatic glucagon has been detected. Gastric inhibitory polypeptide (GIP) inhibits gastric secretion and motility (enterogastrone activity) and together with glucose it stimulates insulin release (incretin activity). Motilin increases lower esophageal sphincter pressure, enhances gastric pepsin secretion and slows down gastric evacuation. Serum levels of pancreatic polypeptide may be found elevated as a diagnostic index in patients with endocrine peptide tumors of the pancreas. Recently, the potential importance of local (paracrine) actions of gastrointestinal polypeptides has been amphasized. Predominantly paracrine activity is exhibited by some prototype hormones, e.g. somatostatin, substance P, bombesian, and the non-polypeptide compounds, prostaglandins.
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PMID:[New views on gastrointestinal hormones]. 85 99

We have used 125I-labeled vasoactive intestinal peptide (VIP) to study the kinetics, stoichiometry, and chemical specificity with which the labeled peptide binds to dispersed acinar cells prepared from guinea pig pancreas. Binding of 125I-VIP to pancreatic acinar cells was moderately rapid, reversible, specific, saturable, and depended on incubation temperature. Deterioration of 125I-VIP incubated with pancreatic acinar cells at 37 degrees was reflected in a decrease in acid-precipitable radioactivity and in the amount of tracer which could bind to fresh acinar cells. On the other hand, 125I-VIP bound to pancreatic acinar cells appeared to be protected from deterioration. VIP and secretin but not glucagon or COOH-terminal octapeptide of cholecystokinin inhibited binding of 125I-VIP to pancreatic acinar cells. The dose-response curve for inhibition of 125I-VIP binding by VIP or secretin was biphasic and suggested that pancreatic acinar cells have two classes of binding sites: (a) a relatively small number of sites with a high affinity for VIP and a low affinity for secretin, and (b) a relatively large number of sites with a low affinity for VIP and a high affinity for secretin. The difference between the relative affinities of VIP and secretin for the high affinity VIP binding sites appears to be primarily attributable to the NH2-terminal portions of these molecules since synthetic COOH-terminal fragments VIP 14-28, VIP 15-28, and secretin 14-27 were equipotent in inhibiting 125I-VIP binding. On the other hand, secretin 5-27, [6-tyrosine] secretin and native secretin were equipotent in inhibiting binding of 125I-VIP to its high affinity site, and these three peptides were 5 times more potent than secretin 14-27 but 10,000 times less potent than native VIP.
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PMID:Interaction of porcine vasoactive intestinal peptide with dispersed pancreatic acinar cells from the guinea pig. Binding of radioiodinated peptide. 94


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