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)

In three groups of patients with insulin-dependent diabetes following total (n = 5) or partial (n = 5) pancreatectomy or chronic pancreatitis (n = 7) and in a group of idiopathic diabetics, ketogenic capacity following insulin withdrawal and during a 24-h fast was studied. Basal glucagon values were significantly increased in all diabetic groups with no significant intergroup differences. Basal ketone body values and their increase during starvation and insulin withdrawal were high and not different in totally pancreatectomized and primary diabetics, both showing unmeasurable C-peptide levels. On the contrary, ketogenesis was reduced in partially pancreatectomized and in pancreatitis diabetics with persistent levels of C-peptide. Our data confirmed the persistence of immunoreactive glucagon after pancreatectomy and demonstrated that ketogenesis is not suppressed in pancreatectomized diabetics and depends above all on residual B-cell function. A possible ketogenic effect of extra-pancreatic glucagon-like substances cannot be excluded.
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PMID:Glucagon levels and ketogenesis in human diabetes following total or partial pancreatectomy and severe chronic pancreatitis. 700 39

Late results were obtained from the follow up of 48 patients with chronic pancreatitis, who underwent partial duodenopancreatectomy. We measured the rest function of the remaining B-cells after resection by daily glucose profile, i.v.-gtt, measurements of the glucagon stimulated C-peptide-output and the amount of C-peptide in the 24-h-urine. In 9% of the cases the operation induced diabetes in addition to the already existing 31%. 3/4 of the nondiabetics showed a latent diabetic metabolism (K value < 1.0). The cause of this, as shown by the C-peptide-analysis, was the loss of the endocrine functional reserve following pancreas resection because of chronic pancreatitis. Therapeutically great differences resulted in reaching and equilibrium of serum glucose in the pancreas resected insulin-dependent patients, because they were dependent on carbohydrates for energy. The tendency to hypoglycaemia represented an additional endangerment.
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PMID:[Long-term follow-up study of C-cell-function after partial duodenopancreatectomy (author's transl)]. 700 67

Plasma pancreatic enzymes and hormones were longitudinally observed after producing partial obstruction of the major pancreatic duct in dogs to study an initial state of chronic pancreatitis or pancreatolithiasis. Fasting plasma immunoreactive cationic trypsin was elevated during the first six months and then decreased in a subgroup with pancreatic calculi, marked fibrosis, or duct dilatation when compared with the corresponding opposite at the end of the 12-month period. Similar but less prominent changes were found in fasting plasma immunoreactive pancreatic polypeptide (IRPP). Plasma amylase, glucose, or immunoreactive insulin or glucagon (IRG) show no significant variation. Plasma IRG and IRPP responses to intravenous insulin were reduced in the subgroups with marked pancreatic changes towards the end of the 12-month period. These results suggest that plasma pancreatic enzymes and hormones remain elevated as long as pancreatic damage is mild and then start to decline as the damage progresses in chronic pancreatitis or pancreatolithiasis.
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PMID:Longitudinal changes of plasma pancreatic enzymes and hormones in experimental pancreatolithiasis in dogs. 769 7

The hypothesis was tested that islet autoimmunity is induced by ongoing islet cell destruction in subjects with susceptibility genes HLA-DR 3 and/or DR 4. Sixty-one patients with confirmed chronic pancreatitis were analysed, 30 of whom expressed HLA-DR 3 and/or DR 4. Electron microscopy studies in 10 patients showed that the inflammatory process also affected islets, as recognisable from islet cell lysis, intrainsular fibrosis and immune cell infiltrates. None of the sera tested contained any of three markers of islet autoimmunity, ICA, IAA or GAD antibodies. A correlation was seen between the loss of exocrine function, as determined by the ALTAB-test, and of beta-cell function, as determined by the C-peptide response to i.v. glucagon. However, there was no preferential loss of beta-cell function in patients with HLA-DR 3 and/or DR 4. We conclude that islet cell destruction occurs during chronic pancreatitis, but does not trigger islet autoimmunity, even in the presence of HLA-DR 3 and/or DR 4.
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PMID:Inflammatory islet damage in patients bearing HLA-DR 3 and/or DR 4 haplotypes does not lead to islet autoimmunity. 805 84

In a prospective clinical-experimental study, 15 consecutive patients with chronic pancreatitis, operated on because of severe pain, were examined for the effects of a duodenum-preserving resection of the pancreas head on endocrine pancreas function. This was done by means of oral and intravenous glucose tolerance testing before the operation, on the 10th or 11th day postoperatively, and 3 months after the operation. In addition to glucose levels in the peripheral venous blood, levels of insulin, C-peptide, glucagon, and pancreatic polypeptide were determined. As indicated by the k value, glucose tolerance improved postoperatively in 10 patients (66.6%); three patients (19.9%) showed no change, and one patient (6.6%) was worse. Only one patient (6.6%) developed evident diabetes mellitus immediately postoperatively. Pre- and postoperative levels of insulin and C-peptide showed no significant differences. The fasting levels of glucagon were significantly lower postoperatively than before the operation (p < 0.01). The stimulation of pancreatic polypeptide after oral glucose was significantly lower postoperatively (p < 0.01). Duodenum-preserving pancreas head resection does not lead to an impairment of glucose tolerance in the majority of patients; a deterioration was observed only in few cases (13.3%).
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PMID:Glucose homeostasis and endocrine pancreatic function in patients with chronic pancreatitis before and after surgical therapy. 810 71

The pathogenetic mechanism underlying glucose intolerance in pancreatic cancer is still unclear. We studied the pattern of three glucose regulating hormones (C-peptide, glucagon and GH) in pancreatic cancer patients with (N = 34) and without (N = 8) hyperglycemia, and compared the findings made with those from subjects with other hyperglycemic conditions of well-known origin [type I diabetes mellitus (8 cases) and diabetes mellitus secondary to chronic pancreatitis (13 cases) or liver cirrhosis (4 cases)]. In hyperglycemic pancreatic cancer patients, C-peptide was absent in 26% of the cases, reduced in 24%, elevated in 29% and within the normal range in the remaining 21%. In normoglycemic pancreatic cancer this hormone was reduced in two cases (25%) and within the normal range in all the others. GH was within the normal range in all cases: glucagon was below the normal range in some hyperglycemic pancreatic cancer patients (41%) or within the normal range in all the remaining patients. No correlations were found between the three hormones when findings from subjects were considered all together. However, in pancreatic cancer C-peptide and glucagon presented consensual variations. C-peptide, glucagon and GH levels were not related to tumor volume; glucagon was found to be associated with liver metastases. C-peptide was correlated with serum ALT and ALP. We may conclude that hyperglycemia associated with pancreatic cancer may be caused by different mechanisms. In some cases a reduced secretion of both insulin and glucagon was observed, as occurs in chronic pancreatitis. In the majority of patients, beta cell function appears normal, and the hyperglycemic state may depend on an altered peripheral sensitivity to insulin due to the pancreatic pathology itself or to consensual liver involvement.
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PMID:C-peptide pattern in patients with pancreatic cancer. 813 97

The clinical investigations carried out in a 58 years woman complaining of malaise led to the discovery of an hypoglycaemia resulting from a secreting pancreatic insulinoma. In addition, a chronic pancreatitis, an endocrine hyperplasia (possible nesidioblastosis) and a villous adenomatosis of the pancreatic duct were diagnosed on two biopsies. The immunohistological tests performed on the insulinoma showed insulin, calcitonin and gastrin labelled cells. Electron microscopy displayed numerous neurosecretory granules. The peritumoral endocrine hyperplasia contained intermingled B, A and D cells respectively labelled by insulin, glucagon and somatostatin. Following the operation, the patient recovered without recurrence of the hypoglycaemia (three year follow-up). Factors which may explain such a rare pathological association are discussed.
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PMID:[Pancreatic insulinoma, adenomatosis of the Wirsung's duct and chronic pancreatitis. Apropos of a case]. 813 87

In clinical practice, exogenous pancreatic enzymes are administered for the treatment of pancreatogenic steatorrhea or with the intention to relieve pain due to chronic pancreatitis. Moreover, a large number of patients take pancreatin (i.e., exogenous pancreatic enzymes) for functional dyspepsia. The effect of exogenous pancreatic enzymes on the enteropancreatic axis is a complex issue. Intraduodenal but not intrajejunal protease activity appears to exert a dose-dependent negative feedback on exocrine pancreatic secretion. Only enzymes with a proteolytic activity but not amylase and lipase exert a control on pancreatic secretion. The mechanism responsible for this feedback regulation is debated, but the cholinergic system seems to play a major role. Intraduodenal pancreatic enzymes (pancreatin) lead to an increased release of pancreatic polypeptide but do not affect the release of insulin and glucagon. In addition, pancreatic enzymes have an influence on the release of some gastrointestinal hormones (i.e., cholecystokinin, motilin, gastric inhibitory polypeptide). Neither exogenous nor endogenous pancreatic enzymes seem to play a major role in the regulation of interdigestive gastrointestinal motility. However, an adequate rate of postprandial pancreatic output is required to control gastric emptying. Current knowledge on the effect of exogenous pancreatic enzymes on the enteropancreatic axis, gut peptide release and gastrointestinal motility are updated in the present article.
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PMID:Effect of exogenous pancreatic enzymes on gastrointestinal and pancreatic hormone release and gastrointestinal motility. 822 68

Chronic alcoholic pancreatitis (CAP) is often complicated by the onset of diabetes mellitus. The aim of this study was to assess the residual beta cell function (evaluated by means of the glucagon test) and the mean disposal rate of insulin (with the insulin tolerance test) in 66 CAP patients with or without abnormalities of glucose metabolism and in 19 control subjects. On the basis of our data, we conclude that the glucose metabolism abnormalities in chronic pancreatitis occurs as a result not merely of impaired production of endogenous insulin, but also as result of a combination of the latter together with insulin resistance.
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PMID:Diabetes in chronic alcoholic pancreatitis. Role of residual beta cell function and insulin resistance. 844 82

From the present review it appears that insulin-dependent diabetes is a common finding in chronic pancreatitis, and impaired secretion of insulin from beta-cells of the pancreatic islets is essential for the development of this form of secondary diabetes. Judged from a positive correlation between insulin secretory capacity and stimulated pancreatic enzyme output, beta-cell function may decrease in parallel with exocrine pancreatic function. However, in patients with insulin-dependent diabetes secondary to chronic pancreatitis beta-cell function was preserved to a greater extent and glucoregulation was better than in comparable Type 1 (insulin-dependent) diabetic patients. Immunological phenomena and associations with certain HLA-alleles characterizing Type 1 diabetes mellitus were not found in insulin-dependent diabetes secondary to chronic pancreatitis. This may contribute to the slower destruction of the beta-cells in chronic pancreatitis than encountered in Type 1 diabetes. The small number of chronic pancreatitis patients who developed totally absence of endogenous insulin production still have some alpha-cell function during i.v. arginine and meal stimulation. However, insulin-induced hypoglycemia and insulin withdrawal did not stimulate glucagon secretion in the secondary diabetic patients in contrast to comparable Type 1 diabetics. Nevertheless, blood glucose counterregulation is intact in the secondary diabetics due to preserved catecholamine secretion. Furthermore, ketonemia develops during dissipation of insulin, in spite of absence of increased glucagon secretion, emphasizing the role of insulin dissipation for the development of ketoacidosis in this form of diabetes. The suggested increased susceptibility to severe hypoglycemia and less tendency to development of ketonemia may further be influenced by altered insulin sensitivity, nutritional factors and concomitant hepatic failure in diabetes secondary to chronic pancreatitis. Pancreatic polypeptide secretion was absent in chronic pancreatitis without endogenous insulin production. Pancreatic polypeptide secreting cells thus seem to be at least as vulnerable as the beta-cells to the destructive processes characterizing chronic pancreatitis, whereas glucagon secreting alpha-cells preserve secretory capacity to a greater extent than PP-cells and beta-cells. No data, however, favour the view that absent pancreatic polypeptide secretion has any major effect on the glucoregulation in diabetes secondary to chronic pancreatitis. Increased plasma concentration of somatostatin was found in patients with insulin-dependent diabetes secondary to chronic pancreatitis. The source of somatostatin in the patients is unknown, but somatostatin may contribute to a reduction in overall blood glucose level in patients without endogenous insulin secretion due to inhibition of glucagon secretion.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Diabetes mellitus secondary to chronic pancreatitis. 849 94


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