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)

A portacaval shunt (PCS) model is frequently employed to study phenomena inherent in portal-systemic shunting of splanchnic blood. In many species, a PCS induces hepatic insufficiency, accompanied by encephalopathy. Rats operated on with a 'nonsuture' technique tolerate a PCS better and exhibit no or only slight encephalopathy. Age and environment seem to have a large impact on the ability to tolerate a PCS. This explains the discrepancies between the results of different investigators and the varying time periods reported between the PCS operation and the optimal time for experiments. To characterize the PCS model (button technique) in rats with respect to metabolic parameters in our field of interest, we studied three groups of male Sprague-Dawley rats--non-operated (n = 12); sham-operated (n = 12) and PCS (n = 13)--for 4 weeks following surgery. Body weight in the PCS group decreased for 1 week after surgery and then increased at about the same rate as in the control groups. Plasma immunoreactive insulin, plasma immunoreactive glucagon (IRG) and aromatic amino acid concentrations were highest 1 week after surgery and tended to normalize in the next weeks. Plasma branched-chain amino acid (BCAA) concentrations were decreased in the 1st, 2nd and 3rd week after surgery, after which normalization occurred. These data demonstrate that after 3-4 weeks, male Sprague-Dawley rats start to recover from the metabolic disturbances caused by PCS with regard to the parameters measured. Therefore, experiments in this area, especially those relating to BCAA metabolism, should be carried out 2-3 weeks after the shunt operation (button technique).
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PMID:Sequential metabolic characteristics following portacaval shunt in rats. 308 3

The multisystem involvement in acute pancreatitis (AP) is a reflection of the pancreatic gland's capacity to produce a number of potent vasoactive peptides, hormones, and enzymes. The various prognostic criteria are early evaluations of these metabolic derangements. The pathogenesis of hypocalcemia, long recognized as an indicator of severity of AP, is multifactorial. Imbalances of parathyroid hormone (PTH)-calcitonin, the interactions of glucagon, gastrin and other pancreatic hormones with PTH-calcitonin, the role of free fatty acids in binding serum calcium with albumin, and the translocation of calcium ion in muscles and liver, have been recently described but remain conflicting theories. Yet, the time-honored theory of calcium-soap formation enjoys wide acceptance. Hyperglycemia, hypoglycemia, and occasional ketoacidosis in acute pancreatitis have been studied thoroughly. The complex cause-and-effect relationship between hyperlipidemia with acute pancreatitis needs further study. The coagulation abnormalities seem to be initiated by activated trypsin, and their role in microvascular coagulation appears to form a unifying hypothesis for major organ dysfunction, but this requires further investigation. Adult respiratory distress syndrome may be the result of active enzymes that digest pulmonary surfactant and/or microvascular thrombosis. The depression of cardiac function and shock are suspected to be secondary to vasoactive peptides such as bradykinin, or myocardial depressant factor, whose structure has yet to be elucidated. The renin-angiotensin alterations and renal complications in acute pancreatitis have received scant attention in the literature. The onset of moderate visual disturbances, or even blindness, in a patient with acute pancreatitis as a result of retinal vessel thrombosis is fortunately uncommon. Rare but interesting are the manifestations such as subcutaneous fat necrosis, arthralgia, and pancreatic encephalopathy. Despite the extensive literature on the complexities of the pathogenesis of complications of acute pancreatitis, there have been very few advances in the prevention and management of specific complications. It is hoped that further work on modification of enzymatic disturbances induced in acute pancreatitis will result in its effective treatment and prevention of serious complications.
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PMID:Systemic complications of acute pancreatitis. 328

An amino acid solution enriched in branched chain amino acids (BCAA) was administered to cirrhotic patients with encephalopathy and serial determinations of serum glucose, IRI and IRG were performed. Slight decrease of serum glucose was observed when only BCAA was given. On the other hand, when BCAA was infused with glucose, the serum glucose level decreased significantly after infusion (-77.5 +/- 26.2 mg/dl, p less than 0.01) and two cases of hypoglycemic shock were observed. Although both serum insulin and glucagon increased in these cases, the IRI/IRG molar ratio which was 8.9 at the start of infusion increased to 20.6 at the end of infusion. It was suggested that administration of BCAA with glucose caused hypoglycemia in cirrhotics with encephalopathy, possibly by synergistic action of BCAA and glucose on serum insulin level.
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PMID:Effects of branched chain amino acid infusion on glucose metabolism in cirrhotic patients with encephalopathy. 636 5

Plasma amino acid patterns were determined before and after hemofiltration (HF) and hemodialysis (HD) in 6 patients with portal systemic encephalopathy (PSE) and compared with the plasma AA patterns of 16 patients with chronic renal failure (CRF) treated either by HF or HD. The branched-chain amino acids (BCAA) increased paradoxically in PSE patients during HF but not with HD. There were no differences in BCAA's with HF as compared to HD in the CRF patients. The amount of amino acids lost was the same with both treatment modalities and in both patient groups. Much of the amino acids lost were released from the intracellular space. The BCAA release was significantly higher in PSE patients during HF. No correlation was found between plasma insulin, glucagon, and cortisol levels and BCAA release. An inverse correlation was found between the amount of BCAA's released from the intracellular space and the plasma ammonia levels. It is suggested that a selective cellular transport mechanism for BCAA exists which is inhibited by high plasma ammonia levels in PSE.
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PMID:Increased plasma ammonia may inhibit cellular release of branched-chain amino acids in systemic portal encephalopathy. 658 71

Acute hepatic ischaemia was induced in pigs by means of a portacaval shunt with hepatic artery ligation after 24 hours. Despite significant elevation in blood ammonia, fatty acids, aspartate aminotransferase, cerebrospinal fluid glutamine and ammonia, and brain tissue glutamine, ammonia and tryptophan, the experimental animals remained awake and alert and indistinguishable from sham-operated controls. The molar ratio of branched-chain to aromatic amino acids fell sharply in the arterial blood, but showed a terminal attempt at compensation in muscle venous samples. Portal and muscle venous insulin levels were elevated, and glucagon values rose in all circulation segments in the experimental group. The failure to induce coma in these pigs, despite the presence of many of the classical biochemical features, suggests that the syndrome of encephalopathy comprises several stages, and that the pig may be an important model in which to define these.
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PMID:Acute hepatic ischaemia in the pig- the changes in plasma hormones, amino acids and brain biochemistry. 725 Aug 93

Pancreatic glucagon (IRG) levels in the postabsorptive (fasting) state and in response to arginine test (ATT), have been investigated in 17 subjects with porto-caval anastomosis (PCA). Out of these, seven subjects were insulin-treated diabetics, 5 were untreated diabetics, and 5 had no evidence of clinical diabetes. Basal and stimulated IRG values in the overall group of PCA subjects were significantly increased in comparison to 14 normal controls. No significant difference was found between the three groups of patients in respect to IRG values. The mean fasting IRG levels, grouped in relation to the age of shunt, were significantly raised six months after surgery. In addition no significant difference in IRG values (fasting or stimulated) was observed in relation to the entity of the liver disease (child degree) or to the type of surgical shunt. Finally, when PCA patients with or without encephalopathy were considered, fasting and peak IRG values were significantly increased in those patients with encephalopathy.
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PMID:Exaggerated glucagon secretion in diabetic and non-diabetic subjects with surgical porto-caval anastomosis. 729 9

Acute alcoholic hepatitis is the first alcoholic lesion of the liver in the process of progression to cirrhosis. It is due to the toxic action of alcohol on hepatocytes, in particular in the centrolobular region. It may affect a liver which is the site of fatty infiltration, fibrosis or cirrhosis, i.e. during all the stages of alcoholic liver disease. Its severity depends upon the degree of alcoholic intoxication. It may be fatal by malignant hepatic failure in a quarter of cases or, at the extreme, be totally asymptomatic. The aims of treatment are: 1) in the immediate, to prevent death; 2) subsequently, to prevent progression to cirrhosis. The majority of the wide range of treatments suggested have been evaluated in controlled trials. It is thus easy to show that corticosteroids are effective in severe acute alcoholic hepatitis, i.e. with encephalopathy and coagulation disturbances, but no in ordinary forms. Although logical, nutritional supplements, whether enteral or parenteral, have no influence on the course of acute alcoholic hepatitis. The same applies to anabolic steroids, the association insulin-glucagon, antifibrosis agents or "hepatoprotectors". The elimination of alcoholic intoxication remains the most important point, accepted by all hepatologists.
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PMID:[Treatment of acute alcoholic alcoholism]. 768 Jan 91

Prognostic factors and the efficacy of therapy were studied on 518 patients with fulminant viral hepatitis collected as a joint study from the active members of the Japanese Gastroenterological Society during the period from 1983 to 1988. Using five independent prognostic variables (patients' age, occurrence of infection, gastrointestinal bleeding, renal failure and coexistence of accompanying diseases), a prognosis discriminating logistic model was constructed. A risk score was calculated from the model and patients were classified into two groups with high and low probabilities of survival according to the score. In patients with the duration of illness more than ten days before development of encephalopathy, survival rate of patients given Fischer's amino acid solution was significantly low compared with those not given in the group of low survival probability. A similar deleterious effect of the amino acid solution was proven with another logistic model comprising three more covariates (prothrombin percent, total birirubin level on the day of development of hepatic encephalopathy and the duration of illness before encephalopathy) on 391 patients without missing data on these items. No significant life saving effect was observed on plasma exchange, charcoal hemoperfusion, glucagon-insulin therapy, H2 receptor antagonist and steroid. By Cox's proportional hazard model, plasma exchange was found to double the survival period of patients after development of encephalopathy (p < 0.001).
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PMID:[Evaluation of the special therapies in fulminant viral hepatitis--a multi-institution study]. 786 29

Zinc deficiency is common in cirrhosis and has been involved in the altered nitrogen metabolism. In this study, we measured the effects of zinc supplementation on the dynamics of amino acid-derived urea synthesis in cirrhosis with mild or latent encephalopathy. The hepatic conversion of amino acids into urea was studied in eight patients with advanced cirrhosis under controlled conditions of substrate availability (continuous alanine infusion), before and after 3-month oral zinc sulfate supplementation (600 mg/d). Eight more patients, matched for hepatocellular failure and encephalopathy, served as controls. Plasma zinc levels were reduced in all patients and returned to normal after oral zinc. The alanine-stimulated urea nitrogen synthesis rate in relation to alpha-amino-N concentration--the functional hepatic nitrogen clearance--increased by 25% after zinc supplementation, i.e., more urea was produced at any alpha-amino-N concentration. Basal and alanine-induced glucagon decreased by 50%, and the ammonia response to alanine decreased by 30%. Psychometric tests improved, as did routine and dynamic liver function tests and the Child-Pugh score. Also, the plasma concentration of lipid peroxides was reduced by zinc. No significant changes were observed in the control group. Our data indicate that long-term oral zinc speeds up the kinetics of urea formation from amino acids and ammonia. Changes in the hormonal drive and/or the antioxidant activity of zinc might be involved in the general improvement in liver function, whereas the beneficial effects on encephalopathy might stem from decreased ammonia.
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PMID:Zinc supplementation and amino acid-nitrogen metabolism in patients with advanced cirrhosis. 862 Nov 38

We report a 28-year-old young male with MELAS syndrome (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes) presenting with two previous episodes of stroke-like manifestation, lactic acidosis and mitochondrial cardiomyopathy. He was also affected with insulin-dependent diabetes mellitus (IDDM), as diagnosed by the experience of diabetic ketoacidosis (DKA), and dependence on insulin therapy. On admission, the serum lactate level was found to be increased to 5.4 mmol/l, and plasma glucose level to 7.9 mmol/l with haemoglobin A1c 8.4%, while he was using insulin 26-30 units per day. Physical examination revealed a short stature male of height of 150 cm and weight of 49 kg. Mild mental retardation with bilateral sensorineural hearing impairment was observed. After glucagon stimulation, C-peptide levels rose from 0.46 nmol/l to 0.53 nmol/l, indicative of impaired insulin secretion. Anti-glutamate decarboxylase (anti-GAD) antibody was positive. In addition, human leucocyte associated antigen (HLA) typing showed DR3 and DR4, suggesting the strong contribution of autoimmunity to the pathogenesis of IDDM in this patient. Moreover, the result of a treadmill exercise test was positive due to inferior wall myocardial ischaemia. Cardiac catheterization and endomyocardial biopsy disclosed a normal coronary angiogram and confirmed the diagnosis of mitochondrial cardiomyopathy. Molecular genetic analysis of his family revealed a sporadic occurrence of mitochondrial DNA (mtDNA) mutation at base pair (bp) 3243. The degree of heteroplasmy of mtDNA mutation from a total of 19 passages of skin-derived fibroblasts from this patient showed a slightly downward trend. This extremely rare case of sporadic MELAS syndrome with autoimmune IDDM harbouring mtDNA mutation highlights the possible pathogenetic role of mtDNA mutations in autoimmune disease.
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PMID:Autoimmune IDDM in a sporadic MELAS patient with mitochondrial tRNA(Leu(UUR)) mutation. 982 17


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