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)

Peptide antagonists might be useful tools in elucidating a potential role for neuropeptides in islet hormone secretion. We therefore investigated the effects of three different peptide receptor antagonists on insulin and glucagon secretion in vivo in mice. The gastrin-releasing peptide (GRP) antagonist N-acetyl GRP-(20-26) amide (P less than 0.01) and the vasoactive intestinal polypeptide (VIP) antagonist [4Cl-D-Phe 6,Leu17] VIP (P less than 0.001) specifically inhibited insulin secretion induced by GRP and VIP, respectively. Furthermore, N-acetyl GRP-(20-26) amide specifically inhibited GRP-stimulated glucagon secretion (P less than 0.01) and the cholecystokinin (CCK) antagonist L-364,718 inhibited CCK-8-mediated insulin and glucagon secretion (P less than 0.001). However, neither of these three antagonists affected insulin or glucagon secretion stimulated by autonomic nerve activation (induced by 2-deoxy-glucose (2-DG)). We conclude that these peptide antagonists can be used in studies on the physiological involvement of GRP, VIP and CCK in islet hormone secretion. Furthermore, neither GRP or CCK seems involved in the insulin and glucagon response to 2-DG in the mouse.
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PMID:Peptide receptor antagonists in the study of insulin and glucagon secretion in mice. 196 11

The BB/W strain of rats develop spontaneous insulin-dependent diabetes. Diabetic BB/W rats have a marked insulinopenia and greatly diminished levels of insulin in their pancreas. Using a radioimmunoassay for rat pancreatic polypeptide (PP), we have examined the content of PP in extracts of the total pancreas and also the regional PP concentration of the three pancreatic lobes. Radioimmunoassays for glucagon, somatostatin (SRIF) and insulin were also made on these extracts. Compared with nondiabetic BB/W rat pancreas, pancreatic extracts from severely diabetic BB/W rats contained 30% as much PP, 31% as much glucagon, 19% as much SRIF, and 0.5% as much insulin. The rat PP radioimmunoassay was used to determine the elution pattern of PP-like antigens in gel chromatography fractions and to measure in vitro secretion of PP from perifused pancreatic slices obtained from diabetic and nondiabetic animals. PP-like immunoreactivity was observed in two zones in the elution from the gel columns when extracts from normal or diabetic rats were chromatographed. The major zone of immunoreactivity eluting at the volume expected for intact monometric rat PP accounted for 67% of the PP-like immunoreactivity in the case of nondiabetic rats and greater than 80% of the PP-like immunoreactivity found in extracts from severely diabetic rats. The minor zone of PP-like immunoreactivity eluted at a volume similar to the position of tetradecapeptide SRIF contained the remainder of detected PP-like immunoreactivity. Tissue slices from diabetic rats secreted more PP and glucagon than slices from nondiabetic rats when slices were perifused with a medium containing leucine, carbachol, and cholecystokinin, even though diabetic pancreas has smaller amounts of PP, glucagon, SRIF, and insulin. Stimulated insulin secretion was virtually absent when tissue slices from diabetic rats were perifused. These results indicate that in the BB/W diabetic rat: (a) pancreatic glucagon, PP, and SRIF are moderately decreased and insulin levels are drastically reduced, (b) lower levels of degraded or low molecular weight form of immunoreactive PP occurs in the diabetic rat pancreas compared to the normal rat, (c) the diabetic pancreas secretes more PP and glucagon and much less insulin than pancreas from nondiabetic rats when perifused under stimulating conditions. The diabetes occurring in the BB/W appears to be a severe type I diabetes characterized by reduced content of insulin, glucagon, SRIF, and PP in the pancreas of these animals. However, secretion of glucagon and PP were not reduced in this in vitro system.
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PMID:Pancreatic polypeptide and other pancreatic hormones in spontaneously diabetic BB/W rats. 198 Jul 35

Cholecystokinin is a choleretic in dogs. Some of the effects of cholecystokinin in stimulating bile flow in dogs are produced by cholecystokinin stimulating the release of other choleretic hormones such as insulin and glucagon. The purpose of this study was to determine the effects of cholecystokinin receptor antagonists on canine hepatic bile flow and insulin and glucagon release from the pancreas. Cholecystokinin octapeptide (CCK-8) and intraduodenal fat were administered to dogs that had undergone cholecystectomy with chronic biliary fistulas with and without the administration of cholecystokinin receptor antagonists. Bile secretion and systemic venous insulin, glucagon, and cholecystokinin levels were measured. The cholecystokinin receptor antagonists benzotript and CR 1409 had no effect on bile flow or hormone levels when administered without cholecystokinin, whereas proglumide produced a large increase in bile flow without altering hormone levels. The response produced by proglumide may be the result of an osmotic effect produced by the substance being secreted in bile and its stimulating bile salt secretion in bile. CCK-8 and intraduodenal fat increased bile flow, bile chloride secretion, and cholecystokinin, insulin, and glucagon concentrations in venous blood. The cholecystokinin receptor antagonists benzotript and CR 1409 significantly decreased the bile flow and insulin and glucagon changes produced by exogenous CCK-8. The effect of intraduodenal fat on bile flow was not inhibited by the cholecystokinin receptor antagonists, whereas the increased insulin and glucagon levels were decreased significantly. Intraduodenal fat may release other choleretic hormones not affected by cholecystokinin receptor antagonists. The choleresis produced by exogenous CCK-8 is inhibited by cholecystokinin receptor antagonists, perhaps by inhibiting the release of the choleretic hormones insulin and glucagon.
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PMID:The effect of cholecystokinin-receptor antagonists on cholecystokinin-stimulated bile flow in dogs. 200 May 61

Feeding responses to continuous intravenous administration of graded doses of the COOH-terminal octapeptide of cholecystokinin (CCK-8) and pancreatic glucagon, alone and in combination, were determined in dogs fasted 4 h. Low doses of glucagon (50, 500, 5,000, 6,000 pmol.kg-1.h-1) had no effect on food intake, whereas higher doses (12 and 24 nmol.kg-1.h-1) depressed intake by 50-60%. Of the CCK-8 doses administered (50 and 400 pmol.kg-1.h-1), food intake was depressed only at the higher dose (53%). This effect was blocked by glucagon (50-5,000 pmol.kg-1.h-1). Simultaneous administration of 50 or 500 pmol.kg-1.h-1 of glucagon and 50 pmol.kg-1.h-1 of CCK-8, doses currently thought to produce plasma peptide levels similar to those occurring postprandially in dogs, had no effect on food intake. These results suggest that plasma levels of CCK and glucagon after a meal are not sufficient alone or in combination to produce satiety.
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PMID:Interaction of cholecystokinin-8 and pancreatic glucagon in control of food intake in dogs. 201 41

Duplex ultrasound was used to investigate superior mesenteric artery haemodynamics in humans in order to determine the physiological importance of postprandial blood concentrations of cholecystokinin octapeptide (CCK8), gastrin 17, secretin, and glucagon and to study whether a nervous cholinergic reflex mechanism has a role in the postprandial mesenteric blood flow response. Duplex parameters of vessel diameter, mean velocity, and flow volume were determined serially in the basal state and after stimulation. Changes were compared with baseline values. Superior mesenteric artery parameters were significantly increased over baseline values after a liquid test meal, but ingestion of saline did not cause any changes. Hormones infused simultaneously at postprandial concentrations did not change mesenteric blood flow. When they were infused at pharmacological doses, however, a significant increase in flow parameters was observed. Pretreatment with atropine significantly (p less than 0.05) reduced the mesenteric blood flow response to meal stimulation (57%). These data suggest that the four hormones tested are not of quantitative importance in regulating postprandial superior mesenteric artery blood flow. A cholinergic nervous reflex, however, participates in the control of food induced mesenteric artery flow changes.
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PMID:Regulation of postprandial mesenteric blood flow in humans: evidence for a cholinergic nervous reflex. 175 82

In the present study we have examined if the different composition of intravenously administered amino acid solutions is of importance for the effect of cholecystokinin (CCK) on pancreatic insulin and glucagon release in dogs. In 6 conscious dogs CCK-9 was infused intravenously at stepwise increasing doses of 5, 10 and 20 pmol/kg.h during an intravenous background infusion of Aminosteril or Aminoplasmal. Aminosteril contains more insulinogenic amino acids while Aminoplasmal contains more glucagonogenic amino acids. CCK elicited a significant stimulation of insulin levels by 10 microU/ml (p less than 0.01) in the presence of i.v. Aminosteril compared to that elicited by i.v. amino acids alone. Glucagon and glucose levels remained unchanged. During i.v. Aminoplasmal CCK-9 had no effect. Since in dogs the physiological plasma amino acid pattern following the ingestion of protein-rich meals is unknown the possibility cannot be excluded that in dogs CCK acts as a mediator of the intestinal signal which augments insulin release during ingestion of protein-rich meals.
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PMID:Composition of amino acid infusions and effect of cholecystokinin on insulin release in dogs. 210 98

To assess the influence of enteric factors on insulin action, seven lean healthy subjects were studied under conditions of hyperinsulinemic euglycemic glucose clamp, double isotope administration, and enteral vs. parenteral glucose infusion. In random order, glucose and mannitol radiolabeled with [2-3H]glucose were infused intraduodenally for 4 h while the systemic rate of glucose turnover was assessed by [6-14C]glucose. During the final hour of the study, plasma glucose, insulin, C-peptide, glucagon, cholecystokinin, and neurotensin were similar under both experimental conditions. Despite an increase in gastric inhibitory polypeptide concentration during combined enteral and iv glucose infusion to levels that mimicked meal ingestion, total glucose infusion rate, insulin-induced stimulation of glucose uptake, and insulin-induced suppression of hepatic glucose release were comparable to those observed during iv glucose administration. These data indicate that under conditions of modest hyperinsulinemia and euglycemia, gastric inhibitory polypeptide did not influence hepatic or extrahepatic insulin action.
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PMID:Lack of effect of gastric inhibitory polypeptide on hepatic and extrahepatic insulin action. 211 May 75

The endocrine cells in the gastrointestinal tract of the musk shrew were studied immunohistochemically. Eleven kinds of endocrine cells, immunoreactive for serotonin, somatostatin, gastrin, cholecistokinin, gastric inhibitory polypeptide, motilin, secretin, neurotensin, pancreatic glucagon, enteroglucagon and bovine pancreatic polypeptide, were revealed. In the stomach, serotonin-, somatostatin-, gastrin-, pancreatic glucagon- and enteroglucagon-immunoreactive cells were detected. The first three types of cells predominated and were more abundant in the pyloric glands than in the other stomach regions. In the small intestine, all types of endocrine cells were found, each having different distributions and relative frequencies. In the large intestine, 10 types of endocrine cells except cholecystokinin-immunoreactive cells were detected. Serotonin- and bovine pancreatic polypeptide-immunoreactive cells were more numerous in the large intestine than in the small intestine.
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PMID:An immunohistochemical study on the distribution of endocrine cells in the gastrointestinal tract of the musk shrew, Suncus murinus. 213 60

To determine its efficacy and safety in treating obesity, a silicone-rubber balloon was passed into the stomach of 10 nondieting, obese subjects. In a counterbalanced sequence, the balloon was inflated with 400 mL for 1 mo and deflated for 1 mo. Lower intakes of solid and liquid test meals (NS), significantly slower gastric emptying, and concomitant changes in glucose, insulin, glucagon, and cholecystokinin concentrations consistent with slower emptying resulted during balloon inflation. After balloon inflation, one small gastric ulcer developed, which subsequently healed. Significant weight loss occurred during the second and third week of the inflation period (F[1,9] = 5.0, p less than 0.05). However, the weight loss was small and the significant effect did not continue through the fourth week.
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PMID:Gastric balloon to treat obesity: a double-blind study in nondieting subjects. 218 57

1. The 4K-prothoracicotropic hormone (PTTH) or bombyxin and the melanization-reddish coloration hormone of the silkworm Bombyx mori resemble insulin and insulin-like growth factors. 2. The family of adipokinetic/red pigment concentrating hormones has some similarity with glucagon. 3. Members of the FMRFamide family are found in vertebrates as well as in invertebrates. 4. In Locusta, a molecule immunologically and biologically related to amphibian melanophore stimulating hormone has been partially characterized. 5. Enkephalins and enkephalin-related peptides occur in insects and other invertebrates. 6. Peptides belonging to the tachykinin family have been isolated from molluscan (Octopus) salivary glands and from insect nervous tissue (Locusta migratoria). 7. Invertebrate arginine-vasotocin homologs have been isolated from an insect (Locusta migratoria) and from a mollusc (Conus). 8. In Leucophaea, Locusta and Drosophila, peptides resembling those of the vertebrate gastrin/cholecystokinin family have been identified. 9. As the number of different neuro-/gut peptides with possible function(s) as hormone, neurotransmitter or neuromodulator is now estimated to be of the order of a few hundred, more similarities will probably show up in the near future.
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PMID:Homologies between the amino acid sequences of some vertebrate peptide hormones and peptides isolated from invertebrate sources. 218 89


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