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)

Plasma immunoreactive glucagon (IRG) was examined in volunteers with biopsy-proven cirrhosis of the liver after recovery from surgical portal--caval anastomosis. A wide range of increased total plasma IRG concentrations was found after overnight fast in groups of cirrhotic subjects with and without fasting hyperglycemia. Gel filtration chromatography of plasma showed a major component in the 3500-mol wt fraction in all cases so studied. Administration of glucose i.v. caused rapid suppression of total plasma IRG in normoglycemic and non-insulin-dependent hyperglycemic cirrhotic subjects. After administration of oral glucose, total plasma IRG was suppressed rapidly in normoglycemic cirrhotic subjects, while non-insulin-dependent hyperglycemic cirrhotic subjects exhibited delayed but prolonged suppression. Chromatography of selected plasma with glucose-suppressed total IRG showed a major decrease in the 3500-mol wt component in every case. Exaggerated increments of plasma gastric inhibitory polypeptide were demonstrable in both groups of cirrhotic individuals after administration of oral glucose, and it is speculated that this peptide may contribute to stimulation of glucagon secretion in liver disease associated with insulin deficiency.
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PMID:Hyperglucagonemia in liver cirrhosis with portal-systemic venous anastomoses: responses of plasma glucagon and gastric inhibitory polypeptide to oral or intravenous glucose in cirrhotics with normal or elevated fasting plasma glucose levels. 44 82

The response of gastric inhibitory polypeptide (GIP) levels to oral glucose in 11 insulin-dependent diabetics was compared to that in 8 age- and sex-matched healthy controls to determine whether they would show the pattern of GIP hypersecretion reported by other workers in maturity-onset, insulin-independent diabetes. One gram of glucose per kg bw resulted in a higher level of glycemia and a significantly diminished GIP response in diabetics when compared to controls (6,018 +/- 1,337 vs. 11,343 +/- 2,353 pg/ml.180 min min, respectively). There was virtually no beta cell response in the diabetics, as measured by changes in the levels of free insulin and connecting peptide. A significant lowering of glucagon levels occurred in the controls, while an inconsistent response was seen in the diabetics. An insulin infusion test was administered to test the hypothesis that insulin suppresses GIP secretion. Although hyperinsulinism, hypoglycemia, and suppression of endogenous insulin secretion were produced in the controls, no suppression of baseline GIP was detected. Similarly, hyperinsulinism and hypoglycemia failed to suppress baseline GIP levels in the diabetics. These results do not support a direct role for insulin in suppressing GIP in normal or diabetic subjects.
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PMID:Gastric inhibitory polypeptide response to hyper- and hypoglycemia in insulin-dependent diabetics. 45 45

Fasting serum gastrin, cholecystokinin, glucagon, and gastric inhibitory polypeptide concentrations were simultaneously measured in normal subjects and in patients with different degrees of renal failure. Values of gastrin, cholecystokinin, gastric inhibitory polypeptide, and glucagon were significantly higher in all patients with serum creatinine concentrations greater than 3 mg/dl than in controls (P less than 0.01). The degree of renal insufficiency was significantly correlated (P less than 0.05) with serum concentrations of each hormone, but no significant linear correlation existed among the serum concentrations of different gastrointestinal hormones in individuals. Hemodialysis did not significantly alter predialysis serum gastrin, cholecystokinin, or glucagon concentration, but the serum gastric inhibitory polypeptide concentration decreased by 30% (P less than 0.01) after hemodialysis. The disproportionate increases of hormones with antagonistic actions may alter gastrointestinal function in renal insufficiency.
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PMID:Gastrointestinal hormone profile in renal insufficiency. 51 44

A reliable, sensitive, reproducible and specific radioimmunoassay for cholecystokinin-pancreozymin (CCK) has been developed, using rabbit antisera to highly purified porcine hormone. The natural occurring variant of CCK (39-CCK), in which the ordinary CCK is lengthened from its N-terminus by a hexapeptide, labelled with 125J, and repurified by column chromatography on Sephadex G-10 and on SP-Sephadex C-25, was used as tracer. Separation from antibody-bound labelled 39-CCK was carried out using a double antibody procedure. Non-specific interference with the assay system was abolished by ethanol extractions. Highly purified porcine CCK was used as standard. No significant crossreaction was found with gastrin, motilin, vasoactive polypeptide (VIP), gastric inhibitory polypeptide (GIP), natural and synthetic secretin, pancreatic glucagon or insulin. The sensitivity of the assay is approximately 40 pg/ml of test solution. The mean immunoreactive CCK concentration in 45 fasting normal subjects was 222 pg/ml increasing after food ingestion to 480 pg/ml. Somatostatin was able to abolish the stimulated CCK release. Elevated CCK concentrations were found in chronic pancreatitis. Immunohistochemical identification of pancreozymin cells was carried out either in surgical samples or in biopsy material. Approximately 1650 CCK cells per cross-section in the duodenum of humans have been found. The CCK cells usually appeared elongated, oval or pyramidal in shape and were observed to reach the lumen with their apical cell pole.
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PMID:Estimation of cholecystokinin-pancreozymin (CCK) in human plasma and tissue by a specific radioimmunoassay and the immunohistochemical identification of pancreozymin-producing cells in the duodenum of humans. 56 41

Seven rabbits were immunized with a synthetic C-terminal glucagon fragment [15--29] conjugated with bovine serum albumin by means of glutaraldehyde. Antisera for glucagon were produced in all the animals after six injections of the conjugate. One of them revealed a higher titer antiserum (G42), which did not cross react with gut glucagon-like immunoreactive material, secretin, insulin, gastric inhibitory polypeptide or vasoactive intestinal peptide. From the results of inhibition of 125 I-glucagon in binding with the antiserum by various glucagon-related fragments the immunogenic determinant of the antiserum was proved to be in the C-terminal residue of the glucagon molecule, although peptide [17--29] or [21--29] reacted weakly with the antiserum. The plasma glucagon levels measured by antiserum G 42 during an arginine test in five normal subjects were superposed on those obtained by other antiserum (G21), specific for pancreatic glucagon. Furthermore, a comparable standard curve for glucagon was obtained using antiserum G42, when a labelled p-hydroxyphenylacetylated glucagon fragment [15--29] was employed as a tracer. The present study clearly demonstrated that the C-terminal glucagon fragment could yield a specific antiserum for pancreatic glucagon, supporting the proposal that the C-terminal fragment of glucagon is responsible for such specific antisera. Furthermore, it is concluded that immunoassay for glucagon could be performed using the labelled glucagon fragment as a tracer.
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PMID:Production of a specific antiserum by synthetic C-terminal fragment of glucagon. 57 20

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

A radioimmunoassay for the measurement of gastric inhibitory polypeptide (GIP) in unextracted plasma in man has been developed using a rabbit antiserum raised against porcine GIP. Porcine GIP was employed also as standard and to produce a 125I-labelled tracer. The assay was able to distinguish 110 pg/ml GIP from zero in plasma samples. Negligible cross-reactivity was demonstrated with cholecystokinin, insulin, pancreatic polypeptide, glucagon, secretin, and vasoactive intestinal polypeptide. The mean overnight fasting plasma GIP level in 28 normal subjects was 203 pg/ml (range: undetectable--420 pg/ml). Plasma GIP levels rose, within 45 minutes of eating a mixed meal, to a mean level of 1573 pg/ml.
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PMID:Radioimmunoassay of gastric inhibitory polypeptide. 67 95

The effects of gastrin, gastric inhibitory polypeptide, secretin, and the octapeptide of pancreozymin-cholecystokinin on immunoreactive somatostatin release were studied in the isolated perfused dog pancreas. Gastrin at a concentration of 65 ng/ml and the octapeptide of pancreozymin-cholecystokinin at a concentration of 25 ng/ml produced a prompt, but transient statistically significant, twofold rise in mean somatostatin concentration. Secretion at a concentration of 0.3 U/ml and gastric inhibitory polypeptide concentration of 58 ng/ml produced a prompt two- to threefold rise in mean somatostatin release, which persisted throughout the perfusion period. With all four polypeptides the pattern of the somatostatin response resembled that of insulin. It appears that pancreatic somatostatin release is stimulated by gastrointestinal hormones that influence the secretion of insulin and glucagon.
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PMID:The effects of gastrin, gastric inhibitory polypeptide, secretin, and the octapeptide of cholecystokinin upon immunoreactive somatostatin release by the perfused canine pancreas. 90 61

A specific radioimmunoassay for motilin has been developed with the use of antisera to porcine motilin raised in guinea pigs. Highly purified 125-I-motilin was used as the tracer and the sensitivity range was 10 to 320 pg. No cross-reactivity was demonstrated with gastric inhibitory polypeptide, secretin, glucagon, gastrin, cholecystokinin-pancreozymin, or vasoactive intestinal peptide. In dogs with denervated pouches of the fundus of the stomach and Mann-Bollman fistulae, duodenal alkalinization resulted in an increase in gastric motor activity in the fundic pouch with a corresponding increase in serum motilin.
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PMID:Radioimmunoassay for motilin. 112 96

The effects of repeated injections of 75 U crude cholecystolinin-pancreozymin (CCK-PZ) at increasing plateau glucose concentrations achieved by glucose infusion were studied in 15 controls, 8 chronic pancreatitics and 8 mild maturity onset diabetics. In control subjects CCK-PZ alone caused minor insulin release but proportinally greater secretion with increasing blood glucose concentrations. Chronic pancreatitis patients who had normal responses to intravenous glucose responded normally to the CCK-PZ but at significantly higher plateau glucose levels. Diabetics had no response to IV glucose boluses of 5 g or 10 g, but with glucose infusions of 250-500 mg/min had almost normal insulin responses to CCK-PZ. The responses to CCK-PZ plus glucose were greater than either stimulus alone, indicating an interaction between these and the beta cell. These studies suggest that the gut homone-receptor in the beta cell is intact in maturity onset diabetes and chronic pancreatitis, whether the glucose receptor is normal or defective. The peptide-responsible in the crude CCK-PZ is not secretin, glucagon or gut glucagon, but may be gastric inhibitory polypeptide (GIP) since pure CCK-PZ has no insuli releasing properties.
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PMID:Insulin responses to crude cholecystokinin-pancreozymin in normal subjects, in patients with chronic pancreatitis and patients with mild maturity onset diabetes. 115 Aug 59


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