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 system using hepatocyte suspensions in vitro was developed for studying the synthesis of albumin, fibrinogen and transferrin. Conditions for optimum survival of the hepatocyte and for synthesis of these plasma proteins were defined for this system. These conditions included the use of horse serum (17.5 percent, v/v, heat-inactivated), an enriched medium (Waymouth's MB 752/1), an O2 tension of between 18.7 times 10(3) and 26.7 times 10(3) Pa and constant stirring. Albumin, fibrinogen and transferrin synthesis rates were obtained of 0.32 p 0.094(10), 0.12 p 0.030(11) and 0.097 p 0.017(10) [mean p S.D. (n)]mg/h per g of hepatocytes respectively. These rates were maintained for the first 12h of study and synthesis continued at a diminished rate up to 48h. The synthesis of albumin was decreased in a medium containing less amino acids and glucose, but that of fibrinogen was substantially unaffected. ATP concentrations up to 12h and RNA/DNA ratios up to 24h were comparable with values in vivo. The ability to study cells up to 48h permitted us to find that the addition of a mixture of hormones consisting of glucagon, cortisol, tri-iodothyronine and growth hormone enhanced fibrinogen synthesis. Addition of insulin to the above mixture resulted in increased synthesis for albumin and transferrin but not for fibrinogen.
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PMID:Albumin, fibrinogen and transferrin synthesis in isolated rat hepatocyte suspensions. A model for the study of plasma protein synthesis. 114 94

Hormonal changes and whole blood free amino acid levels and their relation to renal function were measured in 12 insulin-dependent diabetic patients after two 10-day periods with a diet consisting of 10% and 20% respectively of the energy as protein. The patients were 15-21 years old and mean duration of diabetes was 12 (5-20) years. Glomerular filtration rate, renal plasma flow, and albumin excretion rate were measured together with plasma concentrations of glucagon, growth hormone, insulin-like growth factor 1 (IGF-1), somatostatin, serum insulin and free amino acids in blood. Glomerular filtration rate was 123 +/- 3 ml/min/1.73 m2 on high protein diet and 113 +/- 3 ml/min/1.73 m2 on low protein diet (p = 0.02). Renal plasma flow was unchanged. Glucagon, IGF-1, branch chained amino acids (BCAA), tyrosine, phenylalanine, lysine, and methionine were increased after the high protein diet. Growth hormone, somatostatin, insulin, and other amino acids remained unchanged. The increase in glomerular filtration rate was significantly correlated to the increase in glucagon, isoleucine, and valine (glucagon r = 0.71, p = 0.01, isoleucine r = 0.59, p = 0.04, valine r = 0.62, p = 0.03). In a multiple regression model the increase in glomerular filtration correlated most strongly to the increase in isoleucine, followed by valine and glucagon. Together these variables explained 88% of the total variance of the change in glomerular filtration rate (r2 = 0.88, p = 0.001). Albumin excretion rate was correlated to IGF-1 (r = 0.86, p less than 0.001) on the high protein diet.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Indications that branched chain amino acids, in addition to glucagon, affect the glomerular filtration rate after a high protein diet in insulin-dependent diabetes. 180 76

Albumin synthesis was measured in the isolated perfused rat liver by using the livers of both well-fed and starved rats. Starvation markedly decreased albumin synthesis. The livers from starved rats were unable to increase synthesis rates after the addition to the perfusates of single amino acids or the addition of both glucagon and tryptophan. Arginine, asparagine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, threonine, tryptophan and valine, added together to ten times their normal peripheral blood concentrations, restored synthesis rates to normal. The plasma aminogram (i.e. the relative concentrations, of amino acids) was altered by depriving rats of protein for 48h. The use of blood from the deprived rats as perfusate, instead of normal blood, decreased albumin synthesis rates significantly by livers obtained from well-fed rats. The addition of single amino acids, including the non-metabolizable amino acid, alpha-aminoisobutyric acid, to the above mixture increased albumin synthesis rates to normal values. It is concluded that amino acids play an important role in the control of albumin synthesis and that more than one mechanism is probably involved.
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PMID:The effects of amino acids on albumin synthesis by the isolated perfused rat liver. 465 17

Selective precipitation of triglyceride-rich (TGR) lipoproteins with dextran sulphate and magnesium chloride provides a simple and effective means of determining albumin-bound non-esterified fatty acids, (NEFA) in laying-hen plasma. Albumin-bound NEFA concentrations in the plasma of laying hens fed ad libitum are very low. Most of the NEFA are associated with TGR-lipoproteins, and their concentration is directly proportional (r = 0.82) to TGR-lipoprotein concentration. Subcutaneous injection of glucagon into laying hens produces an approximately 50% increase in total plasma NEFA concentration that persists for at least 2 hr. Most of this increase occurs in the TGR-lipoproteins, but albumin-bound NEFA concentrations increase at least 5-fold before rapidly returning to near control values. These results demonstrate the importance of measuring both albumin- and TGR-lipoprotein-bound NEFA in studies of plasma fatty acid metabolism in the laying hen.
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PMID:A simple method for measuring albumin-bound non-esterified fatty acid concentration in laying-hen plasma. 674 29

A sensitive RNAse protection method was used to show that serine protease inhibitor-1 (Spi-1) is expressed in rat liver and heart, but not in kidney or brain. Bovine somatotropin (bGH) and placental lactogen (bPL) induced rat hepatocyte cultures to express both Spi-1 and IGF-1 mRNA, with bPL approximately 100-fold more potent than bGH. Bovine prolactin (bPrL) did not induce hepatocyte Spi-1 mRNA, demonstrating lack of involvement of lactogenic receptors. Albumin mRNA levels were stable during hepatocyte culturing and were unaffected by growth hormone (GH) treatment, showing that neither culture conditions nor GH treatment affected cellular differentiation. Eliminating serum-free medium hormone supplements one at a time, estradiol, testosterone and T3 were shown to be unnecessary for GH induction of Spi-1, while dexamethasone removal decreased Spi-1 mRNA levels to 10% of GH-stimulated controls. bGH induction of Spi-1 mRNA in the presence of only dexamethasone and glucagon was 75% higher (p < 0.01) than levels seen with insulin also present.
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PMID:Spi-1: an hepatic serine protease inhibitor regulated by GH and other hormones. 814 11

The parenchymal cell fraction was isolated from abattoir adult porcine livers and cultured in Dulbecco's Modified Eagles' medium/Ham's F12 medium (DMEM/F12; 1:1) medium supplemented with 5% foetal calf serum, 10 ng/mL glucagon, 10 microg/mL insulin, 60 ng/mL hydrocortisone and eight other factors (NAIR-1 medium). The fraction contained a number of epithelial cells other than hepatocytes, some of which attached to the culture plates as cell clusters and began to grow after 3 days in culture. These epithelial cells growing as colonies were found to express cytokeratin 18 by immunocytochemistry. After 7-8 days, duct-like structures emerged in the central parts of the colonies. The cells constituting the duct-like structures and some cells located outside the structures were positive for cytokeratin 19 and gamma-glutamyltransferase (GGT). The albumin-positive cells were located in the outer parts of the colonies rather than their central parts. Albumin was also detectable in the cells surrounded by the duct-like structures. Moreover, cytochrome P450 IA1 was induced by 3-methylcholanthrene (3-MC) on day 16. These results suggest that porcine liver epithelial cell clusters may contain stem-like cells which can differentiate into mature hepatocytes or bile duct epithelial cells.
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PMID:Colonial growth and differentiation of epithelial cells derived from abattoir adult porcine livers. 979 36

We have previously shown that immediately after liver transplantation (LT) the porcine recipient exhibits elevated plasma glucagon, increased fractional synthetic rate (FSR) of fibrinogen, and decreased FSR of fixed or structural liver proteins. The purpose of this study was to evaluate the effect of nutritional and hormonal supplementation on these observations 24 h after LT. Two groups of nine pigs were studied 1 day after LT using radioisotopic and arteriovenous difference techniques. A control group underwent LT with saline infusion and a supplemented group underwent LT with infusion of glucose, amino acids (6 and 1.06 mg/kg. min, respectively), and intraportal insulin (0.6 mU/kg. min) and glucagon (1.3 ng/kg. min). Primed constant infusions of [3H]leucine were used to determine leucine flux, an estimate of whole body protein breakdown, and fractional synthetic rates (FSR). The following changes were noted with supplementation: elevated plasma insulin (6 +/- 1 versus 29 +/- 4 microU/ml, control versus supplemented, respectively, P < 0.05), decreased glucagon to normal levels (323 +/- 65 versus 102 +/- 12 pg/ml, P < 0.05), decreased fibrinogen FSR (108 +/- 15 versus 70 +/- 6%/day, P < 0.025), and increased fixed liver protein FSR (8 +/- 1 versus 13 +/- 2%/day, P < 0.05, respectively). Albumin FSR was unaltered by supplementation (8 +/- 2 versus 6 +/- 1%/day, respectively). Nutritional and hormonal supplementation immediately after LT restored the measured protein synthesis in the allograft to near normal levels 1 day after transplantation.
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PMID:The effect of nutritional and hormonal supplementation on protein synthesis immediately after liver transplantation. 992 40

We examined a newborn who had no bile and pancreatic ducts. Hydrops was evident after 29 weeks of gestation and she died shortly after birth, weighing 1,368 g. One of her siblings had died of hydrops at about six months of gestation, and there were two more miscarriages of unknown cause. At autopsy on the newborn, the liver had an abnormally round shape and the pancreas was not in the normal position. There was an ectopic small pancreas with normally developed islets. Histological analysis revealed the complete absence of extra- and intra-hepatic bile and pancreatic ducts. Immunostaining of these tissues showed no positive bile duct marker staining using epithelial membrane antigen and cytokeratin 19 in the liver. Albumin and alpha-fetoprotein staining was positive in the liver, and insulin and glucagon staining was positive in the remaining islets. Thus, this case is characterized by complete absence of bile and pancreatic ducts. These findings suggest the existence of a gene linked to the development of bile and pancreatic ducts.
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PMID:Complete absence of bile and pancreatic ducts in a newborn: a new entity of congenital anomaly in hepato-pancreatic development. 1283 97

Adult human hepatocytes cultured in chemically defined conditions were used as a biological model to examine the metabolic effects of buprenorphine on the human liver. Cell extension and monolayer formation of human hepatocytes were affected in a dose-dependent manner after 24 hr of exposure to the drug. According to the several endpoints evaluated (cellular protein, intracellular lactate dehydrogenase activity and the MTT test), the half-maximal cytotoxic effect (IC(50)) of buprenorphine was close to 100 mum. Longer exposure of hepatocytes to buprenorphine (72 hr) increased its cytotoxicity, and the IC(50) of the drug was reduced to 50 mum. Lower concentrations of the drug (in the 5-50-mum range) significantly impaired the metabolic functions of the hepatocytes. Incubation of the cells with 40 mum-buprenorphine for 24 hr reduced the glycogen content to 60% of the initial content and 50 mum-buprenorphine inhibited glycogen synthesis in glucagon-depleted human hepatocytes by about 40%. Albumin synthesis was the most sensitive metabolic parameter, and 24-hr exposure of hepatocytes to 10 mum-buprenorphine, a concentration with no apparent cytotoxic effects, reduced albumin synthesis to 50%. Urea synthesis was moderately affected by buprenorphine. Glutathione content was reduced in a dose-dependent manner by the drug, reaching a minimum value (60% of control values) after 6 hr of exposure to 50 mum of the opiate. Analysis of the data on the therapeutic dosage of buprenorphine and other opiates showed that the toxicity risk index of buprenorphine, like that of meperidine, lies somewhere between that of morphine and methadone.
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PMID:The effects of buprenorphine on the metabolism of human hepatocytes. 2073 19

We investigated the effects of dietary whey protein on food intake, body fat, and body weight gain in rats. Adult (11-12 week) male Sprague-Dawley rats were divided into three dietary treatment groups for a 10-week study: control. Whey protein (HP-W), or high-protein content control (HP-S). Albumin was used as the basic protein source for all three diets. HP-W and HP-S diets contained an additional 24% (wt/wt) whey or isoflavone-free soy protein, respectively. Food intake, body weight, body fat, respiratory quotient (RQ), plasma cholecystokinin (CCK), glucagon like peptide-1 (GLP-1), peptide YY (PYY), and leptin were measured during and/or at the end of the study. The results showed that body fat and body weight gain were lower (P < 0.05) at the end of study in rats fed HP-W or HP-S vs. control diet. The cumulative food intake measured over the 10-week study period was lower in the HP-W vs. control and HP-S groups (P < 0.01). Further, HP-W fed rats exhibited lower N(2) free RQ values than did control and HP-S groups (P < 0.01). Plasma concentrations of total GLP-1 were higher in HP-W and HP-S vs. control group (P < 0.05), whereas plasma CCK, PYY, and leptin did not differ among the three groups. In conclusion, although dietary HP-W and HP-S each decrease body fat accumulation and body weight gain, the mechanism(s) involved appear to be different. HP-S fed rats exhibit increased fat oxidation, whereas HP-W fed rats show decreased food intake and increased fat oxidation, which may contribute to the effects of whey protein on body fat.
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PMID:Dietary whey protein decreases food intake and body fat in rats. 2133 Oct 67


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