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)

Personal experience with glucagon in 15 cases of acute pancreatitis is reported. Complete remission of pain within 2-3 hr after infusion of the drug was noted in 85% of the series, together with normalisation of blood amylase within 48-72 hr. Glucagon inhibits pancreatic secretio&n. Vairous theories concerning its mechanism of action are examined.
 ...
PMID:[Use of glucagon in the treatment of acute pancreatitis]. 114 73

Ultrastructural and quantitative immunocytochemical studies of rat pancreata were carried out 1 month after adult thymectomy. The proportions of insulin-, glucagon-, and somatostatin-immunoreactive cells in the pancreas were estimated on paraffin sections using the unlabelled peroxidase-antiperoxidase method. Relative islet volume, islet size and number were determined on hematoxylin and eosin stained sections. A moderate increase of the islet volume on account of size was found in the pancreas of the thymectomized rats. The proportion of insulin-immunoreactive cells was also elevated. Ultrastructural studies showed a rich supply of secretory granules in most beta-cells. Mixed beta-endocrine-acinar cells were often observed. Mitotic figures were found in single beta-cells. The blood glucose level was in the normal range. The findings suggest a moderate stimulation of beta-cell secretory activity after thymectomy which is not associated with elevated blood glucose levels.
 ...
PMID:Immunohistochemical and electron microscope studies of rat islets of Langerhans one month after adult thymectomy. 128 30

The recent identification in Heloderma horridum venom of exendin-3, a new member of the glucagon superfamily that acts as a pancreatic secretagogue, prompted a search for a similar peptide in Heloderma suspectum venom. An amino acid sequencing assay for peptides containing an amino-terminal histidine residue (His1) was used to isolate a 39-amino acid peptide, exendin-4, from H. suspectum venom. Exendin-4 differs from exendin-3 by two amino acid substitutions, Gly2-Glu3 in place of Ser2-Asp3, but is otherwise identical. The structural differences make exendin-4 distinct from exendin-3 in its bioactivity. In dispersed acini from guinea pig pancreas, natural and synthetic exendin-4 stimulate a monophasic increase in cAMP beginning at 100 pM that plateaus at 10 nM. The exendin-4-induced increase in cAMP is inhibited progressively by increasing concentrations of the exendin receptor antagonist, exendin-(9-39) amide. Unlike exendin-3, exendin-4 does not stimulate a second rise in acinar cAMP at concentrations greater than 100 nM, does not stimulate amylase release, and does not inhibit the binding of radiolabeled vasoactive intestinal peptide to acini. This indicates that in dispersed pancreatic acini, exendin-4 interacts only with the recently described exendin receptor.
 ...
PMID:Isolation and characterization of exendin-4, an exendin-3 analogue, from Heloderma suspectum venom. Further evidence for an exendin receptor on dispersed acini from guinea pig pancreas. 131 97

To find mammalian analogues of exendin-4, a peptide from Helodermatidae venoms that interacts with newly discovered exendin receptors on dispersed acini from guinea pig pancreas, we examined the actions of recent additions to the vasoactive intestinal peptide/secretin/glucagon family of regulatory peptides. In every respect tested, the truncated form of glucagon-like peptide-1, GLP-1(7-36)NH2, mimicked the actions of exendin-4. Like exendin-4, GLP-1(7-36)NH2 caused an increase in acinar cAMP without stimulating amylase release. GLP-1(7-36)NH2-induced increases in cAMP were inhibited progressively by increasing concentrations of the specific exendin-receptor antagonist, exendin(9-39)NH2. In dispersed acini from guinea pig and rat pancreas, concentrations of GLP-1(7-36)NH2 that stimulated increases in cAMP caused potentiation of cholecystokinin-induced amylase release. Binding of 125I-[Y39]exendin-4 or 125I-GLP-1(7-36)NH2 to dispersed acini from guinea pig pancreas was inhibited by adding increasing concentrations of unlabeled exendin-4 or GLP-1(7-36)NH2. We conclude that the mammalian peptide GLP-1(7-36)NH2 interacts with exendin receptors on dispersed acini from guinea pig pancreas. Exendin(9-39)NH2, a competitive antagonist of the actions of GLP-1(7-36)NH2 in pancreatic acini, may be a useful tool for examining the physiological actions of this peptide.
 ...
PMID:Truncated glucagon-like peptide-1 interacts with exendin receptors on dispersed acini from guinea pig pancreas. Identification of a mammalian analogue of the reptilian peptide exendin-4. 132 31

Ordinary histological investigation has suggested that heterotopic pancreas of the stomach may have two types of histogenesis; one is development from immigrated fetal pancreas tissue, and the other is development from primitive gastric mucosal epithelium following penetration into the submucosa with subsequent erroneous differentiation into pancreas tissue. It is suspected that type-I lesions include the majority of cases caused by immigration from fetal pancreas, and that some type-II cases arise through erroneous differentiation of primitive gastric mucosal epithelium. With regard to immunohistochemical findings, cells positive for pancreatic polypeptide and amylase were much more numerous in the acini of type-I cases compared with type-II cases. Positive cells were found not infrequently in the acini of type-II cases after staining for pancreatic polypeptide, insulin, glucagon, somatostatin, serotonin, and gastrin. On the other hand, a small number of cells in islets were not infrequently positive for alpha 1-antitrypsin, alpha 1-antichymotrypsin, and amylase. It is considered that in the heterotopic pancreas, ductal cells have the potential to differentiate into acinar cells and islet cells, as is the cases in the orthotopic pancreas.
 ...
PMID:Heterotopic pancreas of the stomach. Histogenesis and immunohistochemistry. 137 53

Cystic glucagonoma in contact with insulinoma was found in the pancreas of a 28-year-old female patient with characteristic hypoglycemic syndrome. Among six tumors in total detected in the tail of the resected pancreas, the largest solid tumor (2.5 cm in diameter) consisted mostly of insulin-containing cells with conspicuous amyloid deposition. Contiguous to this tumor, the second largest nodule, measuring 1.8 cm in diameter, showed cystic changes and consisted of glucagon-containing cells. High concentration of immunoreactive glucagon was demonstrated in the cystic fluid. In addition to the cystic changes of endocrine pancreatic tumors, simultaneous occurrence of glucagonoma in contact with insulinoma appears to be extremely rare and repeated episodes of hypoglycemia may contribute to its pathogenesis.
 ...
PMID:Cystic pancreatic glucagonoma in contact with insulinoma found in a hypoglycemic patient. 143 39

Exendin-3 and exendin-4 are biologically active peptides isolated from venoms of the Gila monster lizards, H. horridum and H. suspectum, respectively. They were isolated using a chemical assay which detects peptides with amino-terminal histidine residues. Both are 39 amino acid peptides containing an amino-terminal histidine and a carboxyl-terminal serine amide and are members of the glucagon superfamily of peptide hormones. When tested in a dispersed pancreatic acinar cell assay, exendin-3 stimulates amylase release and with increasing concentrations causes a biphasic increase in cellular cAMP. In contrast, exendin-4 at concentrations up to 1 microM does not stimulate amylase release and produces a monophasic increase in cellular cAMP despite differing from exendin-3 by only two amino acid substitutions at positions 2 and 3 from the N-terminus. Endogenous Mammalian Analog to Exendins? The differences in biological activities can be explained by the observation that exendin-3 interacts with VIP receptors to stimulate amylase release, whereas exendin-4 does not. Both exendin-3 and exendin-4 interact with a putative exendin receptor on pancreatic acinar cells. The presence of this receptor was determined and defined by the ability of a specific inhibitor, exendin(9-39) amide, to abolish the increase in cAMP observed with 0.1-3 nM exendin-3 or exendin-4. The presence of the exendin receptor, although functionally undefined at the present time, predicts the existence of an endogenous mammalian analog to the exendin peptides.
 ...
PMID:Exendin peptides. 157 68

In a prospective trial 30 patients underwent pancreaticoduodenectomy (Whipple operation) for cancer. They were randomly assigned to receive Somatostatin (SST) (n = 15) or not (n = 15). SST was started at laparotomy with 250 micrograms/h and given over a period of 5 days. A small catheter, which was placed into the duct of the pancreatic remnant, gave access to the pancreatic juice. Volume, amylase, lipase and protein as well as bicarbonate outputs were analyzed. As regards endocrine function, insulin and glucagon plasma levels were measured. The nitrogen balance was calculated. A stimulation test was done on the fifth postoperative day. Six patients (3/3) were assessed as drop-outs. A significant reduction was found for volume, amylase, lipase, protein and bicarbonate with SST, this effect lasting for two days. Lipase however was reduced significantly for 5 days. Pancreatic exocrine function was reduced as well after stimulation, if SST was given. Insulin and glucagon were inhibited with SST, the latter more effectively. We found a positive nitrogen-balance as early as on the second postoperative day in the SST-group, whereas without SST this did not occur before the fourth postoperative day. This findings were significant on the third and fourth postoperative day. The inhibitoric effects of SST, which are demonstrated by our laboratory investigations, conform very well with a more favorable clinical course and a reduction of perioperative morbidity and mortality.
 ...
PMID:[Effect of somatostatin on basal and stimulated exocrine pancreatic secretion after partial duodenopancreatectomy. A clinical experimental study]. 167 16

The effect of synthetic rat amylin (10,100,1000 pmol/l) on glucose (10 mmol/) and arginine (10 mmol/l) -stimulated islet hormone release from the isolated perfused rat pancreas and on amylase release from isolated pancreatic acini was investigated. Amylin stimulated the insulin release during the first (+76%) and the second secretion period (+42%) at 1 nmol/l. The first phase of the glucagon release was inhibited concentration dependently by amylin and completely suppressed during the second phase. Amylin diminished the somatostatin release in a concentration dependent manner. This effect was more pronounced at the first than the second secretion period (1 nmol amylin: 1 phase: -60%, 2.phase: -22%). Amylin was without any effect on basal and CCK stimulated amylase release from isolated rat pancreatic acini. Our data suggest amylin, a secretory product of pancreatic B-cells, as a peptide with approximately strong paracrine effects within the Langerhans islet. Therefore, amylin might be involved in the regulation of glucose homeostasis.
 ...
PMID:Islet amyloid polypeptide (IAPP;amylin) influences the endocrine but not the exocrine rat pancreas. 169 Sep 93

We used a monoclonal antibody against an epitope located in the N-terminal moiety of the rat glucocorticoid receptor to identify the glucocorticoid receptor-containing cells in the rat pancreas. Monospecific polyclonal antisera against insulin, glucagon, somatostatin, and amylase were applied to serial sections in colocalization studies to identify the respective endocrine and exocrine cells. Glucocorticoid receptor immunoreactivity was exclusively present in nuclei and cytoplasm of the beta-cells of pancreatic islets. Western blots using the glucocorticoid receptor antibody resulted in identical 94K immunoreactive proteins in both liver and pancreas. After adrenalectomy, the glucocorticoid receptor immunoreactivity of beta-cells decreased significantly. A computer-assisted method of semiquantitative evaluation of the glucocorticoid receptor immunoreactivity demonstrated a significant decrease in the staining intensity of the beta-cells by 23.5% and in that of insulin antibodies by 10.4%, while amylase immunoreactivity was only slightly decreased. Serum levels of corticosterone determined by RIA decreased from 225 micrograms/ml in sham-operated animals to 55 micrograms/ml in animals 14 days after adrenalectomy, while the tissue content of amylase decreased by 45%. The immunohistochemical findings give circumstantial evidence of the presence of glucocorticoid receptor in beta-cells. We interpret our data as indicating an indirect effect of glucocorticoids on amylase synthesis via a glucocorticoid-insulin-exocrine cell pathway.
 ...
PMID:Immunohistochemical localization of the glucocorticoid receptor in pancreatic beta-cells of the rat. 169 2


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>