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)

Angiography before and after the administration of Glucagon was performed in 33 adult patients with symptoms suggesting a pancreatic lesion. Preferently the pancreatographic effect was evaluated. The results were compared with those of the angiography following the administration of Secretin and Tolazoline. The pancreatographic effect was visualized in 70% of the patients examined with Glucagon and the rate of visualization of the effect with Secretin and Tolazoline was 60% and 74.5% respectively. The representation of the small vessels could be enhanced with Glugacon only in 15% for the arteries and in 12.5% for the veins, whereas using Secretin and Tolazoline the improvement raised up to 78% of the cases. -- The pancreatographic effect as an additional sign is useful in the differential diagnosis of the chronic pancreatitis (mottled) and the carcinoma of the pancreas (defect or absence of the effect).-- The superselective technique is recommendable. Using this method an improvement of the pancreatographic effect can be achieved already. In pharmacoangiography Tolazoline gives better results than Glucagon.
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PMID:[The pancreatographic effect during pharmacoangiography of the pancreas following the administration of glucagon (author's transl)]. 13 54

The effect of glucagon on secretin-stimulated bile flow was evaluated in dogs with chronic biliary and gastric fistulas. Evaluation of the effects of secretin and glucagon alone on hepatic bile flow indicated that the calculated maximal response (CMR) values of the two agents were similar. Secretin increased the bicarbonate concentration in hepatic bile whereas glucagon did not, suggesting basic differences in mechanism of action. Administration of glucagon to secretin-stimulated bile flow produced an increase in bile flow while decreasing the bicarbonate concentration in secretin-stimulated bile. Since the maximal response for bile flow to glucagon and secretin was significantly greater than the maximal response to either agent alone, glucagon produced potentiation of secretin-stimulated bile. Glucagon increased the CMR value of secretin-stimulated bile from 513 mul/min for secretin alone to 692 mul/min for secretin and glucagon. This was associated with no significant change in the values of the respective D50S. These data suggest that glucagon produced a noncompetitive augmentation of secretin-stimulated bile flow and suggest that the two agents do not utilize the same receptor to stimulate bile flow.
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PMID:Effect of glucagon on secretin-stimulated bile flow. 17 45

Cyclic AMP output in the bile in response to intravenous secretin was measured in 11 patients, 12 baboons, and 15 dogs. Secretin was given to patients with bile drainage tubes as an intravenous bolus (1 U per kg). In baboons and dogs both secretin infusion (4 U per kg per hr) and bolus injection (1 U per kg) were used. In baboons cyclic AMP was also determined in liver, extrahepatic duct tissue, and in perfusate from isolated segments of extrahepatic bile ducts. Secretin induced a marked choleresis in all three species. In humans, biliary cyclic AMP concentration increased an average (+/- 1 SE) of 68% +/- 12% and in baboons 4-fold, but no increase occurred in dogs. In baboons, cyclic AMP concentration increased in both bile duct tissue and perfusate from isolated bile ducts concomitant with secretin choleresis, but not in liver. In humans the choleretic effects of sodium dehydrocholate, aminophylline, and glucagon were compared to dibutyryl cyclic AMP (DBcyclic AMP). All agents increased bile flow 2- to 3-fold. Cyclic AMP concentration in bile markedly increased after glucagon and DBcyclic AMP but not after sodium dehydrocholate and aminophylline. We conclude that cyclic AMP is implicated in secretin choleresis in both humans and baboons, but not in dogs. The bile duct appears to be the site of cyclic AMP elaboration induced by secretin in baboons and probably is also in man.
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PMID:Cyclic AMP in secretin choleresis. Evidence for a regulatory role in man and baboons but not in dogs. 17 81

Adenyl cyclase activity of rat pancreatic islet membrane was increased by secretin, pancreozymin, and isoproterenol, while ACTH, glucagon, growth hormone, and insulin had no effect. Both secretin and isoproterenol activations were enhanced by prostaglandin E1 (PGE1) and GTP. Isoproterenol activation was additive with PGE1, as was that of secretin with PGE1, but only in the presence of GTP. Secretin activation in the presence of PGE1 and GTP was equivalent to NaF stimulation. Kinetic analysis indicated that secretin and GTP increased the maximum velocity of the adenyl cyclase and tended to decrease the apparent affinity of the enzyme for ATP. Glucagon activation of islet membrane adenyl cyclase was dependent upon prior treatment of the membrane preparation with EGTA and the use of inhibitors of proteolytic enzymes during the collagenase digestion phase of islet preparation. These results suggest that hormonal regulation of insulin secretion may be affected by PGE1 and guanine nucleotide modulation of the adenyl cyclase activation process.
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PMID:Hormonal regulation of pancreatic islet adenyl cyclase. 17 51

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

Pentagastrin, histalog, glucagon, secretin, and perchlorate were intravenously injected into mice in order to investigate the hormonal regulation of 99mTc pertechnetate uptake by gastric mucosa. Pentagastrin significantly increased uptake; the effect of histalog was weaker. Secretin did not alter the uptake. Glucagon produced some diminution, and perchlorate significantly inhibited gastric uptake. Hormones may play a role in improving the sensitivity and specificity of diagnostic tests for Meckel's diverticulum.
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PMID:Effect of pentagastrin, histalog, glucagon, secretin, and perchlorate on the gastric handling of 99mTc pertechnetate in mice. 18 84

Vasoactive intestinal peptide (VIP) is a potent and efficient stimulator of adenosine 3':5'-cyclic monophosphate (cAMP) accumulation in a human colon carcinoma cell line, HT 29. cAMP accumulation is sensitive to a concentration of VIP as low as 3x10(-12) M. Maximum VIP-induced cAMP levels were observed with 10(-9) M VIP and are about 200 times above the basal levels. Half-maximum cAMP production was obtained at 3x10(-10) M VIP. (125)I-Labeled VIP was found to bind to HT 29 cells; this binding was competitively inhibited by concentrations of unlabeled VIP between 10(-10) and 10(-7) M. Half-maximum inhibition of binding was observed with 2x10(-9) M VIP. Secretin also stimulated cAMP accumulation in HT 29 cells, but its effectiveness was 1/1000 that of VIP. The other peptides tested at 10(-7) M, such as insulin, glucagon, bovine pancreatic polypeptide, somatostatin, octapeptide of cholecystokinin, neurotensin, and substance P, did not stimulate cAMP accumulation. Prostaglandin E(1) and catecholamines stimulated cAMP production but were 1/2.3 and 1/5.5 as efficient as VIP, respectively. Another malignant cell line from the gut, the human rectal tumor cell line HRT 18, is also sensitive to VIP. In HRT 18 cells, VIP stimulated cAMP accumulation with a maximal effect at 10(-8) M; half-maximum stimulation was observed at about 10(-9) M. These results demonstrate the presence of VIP receptors in two malignant human intestinal cell lines (HT 29 and HRT 18) in culture and provide a model for studying the action of VIP on cell proliferation.
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PMID:Vasoactive intestinal peptide: a potent stimulator of adenosine 3':5'-cyclic monophosphate accumulation in gut carcinoma cell lines in culture. 20 77

The effects of gastrointestinal hormones on cAMP accumulation and parathyroid hormone (PTH) release were investigated in dispersed bovine parathyroid cells. Secretin (10 (-7) M) caused a 4- to 6-fold increase in cAMP accumulation, while glucagon, vasoactive intestinal peptide, and gastrin caused little if any stimulation. Cholecystokinin caused a 2- to 3-fold increase in cAMP accumulation at 10(-6) M, but this effect may be related to contamination with endogenous secretin since synthetic cholecystokinin octapeptide had no effect. Maximal intracellular cAMP accumulation due to 10(-7) M secretin was reached within 5 min and returned to control over the next 30-60 min, concomitant with a progressive rise in extracellular cyclic nucleotide. cAMP accumulation was half-maximally stimulated by 5 x 10(-9) to 1 x 10(-8) M secretin and was unaffected by alpha- or beta-adrenergic or dopaminergic blockers. Parallel effects were noted on PTH release : 10(-8) M secretin caused a 20-50% increment in PTH release at 15 min which persisted for up to 2 h; PTH release was stimulated half-maximally by approximately 6--8 x 10(-9) m secretin. The specificity of the observed results for secretin and the lack of effect of adrenergic antagonists suggest the presence of a receptor for secretin on dispersed bovine parathyroid cells. These results also suggest the possibility that secretin may modulate parathyroid function in vivo in the cow.
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PMID:Effect of gastrointestinal hormones on isolated bovine parathyroid cells. 21 98

With the advent of radioimmunoassay and immunocytochemical methods, the peptides of the gastrointestinal tract have been identified and measured. Gastrinoma and insulinoma syndromes have been wall characterized. The pancreatic cholera syndrome and some of the evidence that the major manifestations of this disease may be mediated by vasoactive intestinal peptide have been re-examined. Pancreatic polypeptide seems to be an ideal peptide for study of vagal-cholinergic mechanisms that regulate hormone release; it also appears to be a tumor marker for several types of pancreatic endocrine tumors, particularly those of pancreatic cholera. Secretin and cholecystokinin are important regulators of pancreatic exocrine secretion and have been used to test pancreatic function, but there is little evidence that they account for clinical disease. Glucagon-secreting tumors produce a clinical syndrome of diabetes mellitus and distinctive skin lesions, which can be cured by tumor resection. Hormone-secreting tumors may provide insight into normal gut physiology.
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PMID:Gastrointestinal hormones in clinical disease: recent developments. 21 42

Gastric acid secretion by the parietal cell is a single digestive process involving a continuous interplay between nervous and hormonal stimuli. Gastric acid hypersecretion and hypergastrinemia may represent pathologic disturbance of the normal "gastric phase" of acid secretion (excluded antrum syndrome) or abnormal gastrin secretion from a nongastric source as in the Zollinger-Ellison syndrome. Diagnosis of these two syndromes preoperatively is dependent on immunoassay for serum gastrin. A fall in serum gastrin level after the injection of secretin will distinguish the excluded antrum syndrome from the Zollinger-Ellison syndrome. Which hormone or hormones cause the acid hyposecretion of the watery diarrhea hypokalemia achlorhydria syndrome is still uncertain. Potential candidates include secretin, glucagon (alone or combined with gastrin), vasoactive intestinal peptide and gastric inhibitory polypeptide. Secretin has undergone trials as therapy in peptic ulcer whereas glucagon is under investigation for the treatment of acute pancreatitis because of its dual actions as (1) an enterogastrone and (2) an inhibitor of pancreatic secretion.
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PMID:Current concepts on physiological control of gastric acid secretion. Clinical applications. 23 80


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