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)

Porphyria cutanea tarda (PCT) has a known increased incidence of diabetes mellitus and hepatic involvement. We investigated glucose tolerance and glucoregulatory hormone alterations in seven patients with PCT and correlated these results with hepatic histology by percutaneous liver biopsy. Abnormal glucose tolerance was observed in six of the seven patients (87%). Fasting serum insulin levels were normal range, and normal glucose and growth hormone responses to standard, exogenous intravenous insulin were observed. Fasting serum glucagon and urine free cortisol levels were normal in those patients in whom they were measured. While varying degrees of abnormalities were found on histopathologic exam of the liver biopsies, no patient met the criteria for cirrhosis, and none of the patients demonstrated abnormal levels of insulin counterregulatory hormones commonly seen in cirrhosis. Thus, liver disease may not be the sole cause of the observed glucose intolerance and hyperinsulinemia in PCT patients.
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PMID:Carbohydrate metabolism in porphyria cutanea tarda. 46 44

Cirrhosis is complicated by numerous abnormalities of carbohydrate metabolism although these are seldom of clinical importance. Carbohydrate intolerance is extremely common and is accompanied by hyperinsulinaemia, hyperglucagonaemia and elevated levels of gluconeogenic precursors. The hyperinsulinaemia results from impaired hepatic degradation of insulin while recent evidence suggests that pancreatic hypersecretion is responsible for the elevated levels of glucagon in cirrhosis. The role of hepatocellular damage and portal-systemic shunting in the pathogenesis of these abnormalities is controversial but the derangements in carbohydrate metabolism probably reflect hepatocellular damage rather than portal-systemic shunting.
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PMID:The glucoregulatory hormones in cirrhosis of the liver. 47 36

The present study was performed in order to evaluate the plasma glucose pattern in cirrhotic patients who, in the course of a continuous somatostatin infusion (500 microgram/h), were given pulses of glucagon (1 mg i.v.). In normal as well as in cirrhotic subjects somatostatin infusion provoked a marked reduction of the IRI plasma level and this was uninfluenced by subsequent glucagon administration. The rise in plasma glucose level in response to i.v. glucagon administration during somatostatin infusion was less marked in cirrhotics compared to normal subjects. This can be attributed to a variety of factors such as reduced number of liver cells or quantitative or qualitative changes of the liver cell glucagon receptors. Glucagon does not seem to contribute to the pathogenesis of carbohydrate intolerance in liver cirrhosis.
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PMID:Effect of somatostatin (SRIF) on plasma glucose and insulin response to glucagon in liver cirrhosis. 48 63

After summing up existing theories about the origins and development of functional hepatic encephalopathy, the authors report on the effects of six-hour intravenous infusions of ornithine alphaketoglutarate (60 g dissolved in 500 ml distilled water), administered to 10 patients with ethylic hepatic cirrhosis in conjunction with a normal protein intake (70 g/day). Arterial blood ammonemia, venous blood aminoacidemia and the insulin/glucagon ratio did not vary during or after infusion. This method of treatment therefore seems to meet the protein requirements of these undernourished patients.
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PMID:Effects of ornithine alphaketoglutarate on blood insulin, glucagon and aminoacids in alcoholic cirrhosis. 48 88

Necrolytic migratory erythema is the distinctive cutaneous eruption seen with glucagon-producing tumours of the pancreas. Recognition of this eruption is important because it may lead to the early diagnosis of a glucagonoma. Recently, we saw a patient who had necrolytic migratory erythema, hyperglucagonaemia, and cirrhosis of the liver with no evidence of pancreatic tumour while alive or at autopsy. Serum glucagon levels during the period of observation and during an oral glucose tolerance test suggested that the hyperglucagonaemia was not due to an occult glucagon-producing tumour but may have been the result of advanced hepatic cirrhosis.
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PMID:Hyperglucagonaemia and necrolytic migratory erythema in cirrhosis--possible pseudoglucagonoma syndrome. 51 28

The effect of portasystemic shunt surgery on basal immunoreactive glucagon (IRG) levels, metabolic clearance rate (MCR) and t 1/2 for glucagon decay, and basal systemic delivery rate (BSDR) of glucagon was investigated in paired studies in ten cirrhotic subjects. The degree of hepatocellular dysfunction and extent of portasystemic venous shunting was also recorded. Basal IRG levels were highest in the post-shunt (mean +/- SEM, 382 +/- 73 pg/ml) as compared to the pre-shunt (213 +/- 27 pg/ml; P less than 0.05) cirrhotic and control (53 +/- 13 pg/ml; P less than 0.005) groups. The MCR of glucagon was similar in control (13.0 +/- 1.3 ml/kg/min) and pre-shunt cirrhotic patients (13.3 +/- 1.7 ml/kg/min) but was significantly (P less than 0.02) decreased in the post-shunt cirrhotics (7.6 +/- 1.3 ml/kg/min). The t 1/2 for glucagon decay was similar in the control and cirrhotic groups. The BSDR, an estimate of pancreatic A cell secretion, was increased four-fold (P less than 0.01) in the pre-shunt (3042 +/- 454 pg/kg/min) and post-shunt (2518 +/- 535 pg/kg/min) cirrhotic groups, as compared to controls (750 +/- 244 pg/kg/min). It is concluded that (a) in the presence of cirrhosis, the magnitude of portasystemic shunting is important in determining the degree of hyperglucagonaemia; (b) in preshunt cirrhotics raised basal IRG levels are principally due to A cell hypersecretion of glucagon whereas in post-shunt cirrhotics riased IRG levels reflect both A cell hypersecretion and delayed clearance of glucagon; and (c) acute shunting of splanchnic venous blood away from the liver reduces the clearance of glucagon, suggesting that, in man, the liver contributes to the clearance of circulating glucagon.
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PMID:Glucagon metabolism in normal subjects and in cirrhotic patients before and after portasystemic venous shunt surgery. 51 79

Twelve patients with liver cirrhosis and ten normal subjects were studied. Using a constant intravneous infusion of glucose, insulin and somatostatin over 2 1/2 hours we determined the stteady state plasma glucose level (SSPG) in order to measure insulin resistance. The results demonstrated that the cirrhotic patients were insulin resistant compared to normals and that plasma glucagon does not account for the insulin resistance in these patients.
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PMID:Glucose, insulin and somatostatin infusion for the determination of insulin resistance in liver cirrhosis. 52 Oct 9

The effect of liver disease on glucagon metabolism was examined in nine patients with chronic liver disease who were studied both before and after the creation of a surgical portasystemic shunt. Hepatocellular function did not deteriorate after shunt surgery. However, hepatic perfusion with splanchnic venous blood, as determined by scintisplenoportography, decreased after shunt surgery in six subjects but appeared unaltered in three. Basal plasma immunoreactive glucagon (IRG) levels in the pre-shunt cirrhotic group were significantly greater (p <0.005) than in control subjects and further increased (p <0.05) after shunt surgery. Moreover, the increase in basal IRG after shunt was evident only in patients in whom portasystemic shunting was demonstrably increased by surgery. Despite the higher basal IRG levels postoperatively, shunt surgery in the cirrhotics did not alter basal glucose and insulin levels or the glucose and insulin response to a glucose or protein load. Circulating IRG was heterogeneous in the pre-shunt cirrhotic patients: the 9000 molecular weight fraction comprised 27+/-4%, the 3500 mol. wt. fraction 71+/-4%, and the > 40 000 mol. wt. fraction was minimal. After shunt surgery, the relative proportion of the 9000 mol. wt. fraction of IRG (13+/-3%) decreased significantly (p <0.05) and this fall was associated with a corresponding increase in the 3,500 mol. wt. fraction (84+/-4%). It is concluded that, in cirrhosis, hyperglucagonaemia is: (1) dependent on the degree of portasystemic shunting rather than impaired hepatocellular function; (2) predominantly due to increased circulating 3500 molecular weight glucagon; and (3) not a major factor in the pathogenesis of carbohydrate intolerance in liver disease.
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PMID:Effect of portasystemic venous shunt surgery on hyperglucagonaemia in cirrhosis: paired studies of pre- and post-shunted subjects. 53 93

The effect on free plasma amino acids before and after infusion of 1 mg glucagon was studied at rest after an overnight fast in seven patients with compensated liver cirrhosis and in seven healthy controls. Total aminoacidaemia in cirrhotic patients is significantly higher than in controls. Elevated basal levels in cirrhotics are found particularly in tyrosine, citrulline, tryptophane, threonine, phenylalanine, and methionine whereas ornithine and serine levels are decreased. Save for the redox couple cystine-cysteine which increases, glucagon elicits an decrease in most amino acids that is proportionate to their initial level. Total aminoacidaemia decreases in controls and cirrhotics by 14.6 and 9.1 per cent respectively. Serum ammonia level rises significantly in both groups, urea increases only in controls, uricaemia remains virtually unchanged.
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PMID:The effect of glucagon on free plasma amino acids in cirrhotics and healthy controls. 63 37

Plasma glucagon concentration was elevated 2- to 6-fold in cirrhotic patients with spontaneous portal systemic shunting or surgically induced portacaval anastomosis but was comparable to controls in cirrhotics without portal-systemic shunting. The metabolic clearance rate of glucagon (mol wt 3500) was normal in all of the cirrhotic groups, but the estimated basal systemic delivery rate of glucagon was increased 2- to 6-fold in the hyperglucagonemic patients. The blood glucose response to infusion of glucagon (3 ng per kg per min) was reduced in the cirrhotics with portal-systemic shunting or portacaval anastomosis, and correlated inversely with the delivery rate of endogenous glucagon. Administration of ammonium chloride (3 g) failed to elevate plasma glucagon concentration. It is concluded that hyperglucagonemia in cirrhosis is a consequence of hypersecretion rather than decreased hormonal catabolism. A negative feedback signal may exist between hepatic sensitivity to glucagon and the secretion of this hormone.
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PMID:Hyperglucagonemia in cirrhosis: altered secretion and sensitivity to glucagon. 64 12


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