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)

Tyrosine aminotransferase (TAT) induction by glucagon and dexamethasone in the liver of tumor-bearing chickens was studied and compared with induction in healthy animals. The transplantable tumor was caused by inoculation of cells from a cell line induced by MC29 avian leukosis virus. TAT was hardly detectable in tumor tissue of control and dexamethasone-treated chickens, but it was induced by glucagon to levels which were significant although very low when compared to those in host liver or the liver of non-tumor-bearing controls after glucagon treatment. Dexamethasone failed to induce TAT in host liver at 8 A.M. while it significantly indiced TAT in the normal liver at the same time of the day. Similar failure of TAT induction was not detectable when glucagon was used instead of dexamethasone. Furthermore, it was found that diurnal variations in basal and dexamethasone or glucagon-induced TAT levels are considerably mitigated in host liver as compared to those observed in the liver of healthy animals. The possible reasons for these findings are discussed.
Int J Cancer 1975 Dec 15
PMID:Tyrosine aminotransferase induction in normal and tumor-bearing chickens. 0 Mar 37

Acetylated derivatives of glucagon have been prepared by reacting this hormone under various conditions with acetic anhydride. They have been chemically characterized by the use of a 14C-labeled reagent, by peptide mapping techniques following hydrolysis by pronase and chymotrypsin, and by spectroscopy. Acetylation in sodium acetate (pH 5.5) results in a full substitution of the alpha-amino group of the N-terminal histidyl residue, but in a partial (about 0.3 acetyl group per residue) substitution of the epsilon-amino group of the lysyl residue 12. The monosubstituted (on the alpha-amino group) and the disubstituted (on both amino groups) acetylated components have been separated by chromatography on DEAE-cellulose and CM-cellulose. Acetylation in sodium bicarbonate (pH 8.0) results in a complete substitution of both amino groups and of the hydroxyl groups of the tyrosyl residues 10 and 13. Complete deacetylation of the O-acetyltyrosyl residues occurs upon treatment with hydroxyl-amine. Mono, di and tetraacetylglucagon are homogeneous when analyzed by disc gel electrophoresis; di and tetrasubstituted derivatives show an increased mobility towards the anode. 125I-labeled derivatives of acetylglucagon show higher distribution coefficients in the aqueous two-phase dextran/poly(ethylene glycol) system than do similar derivatives of glucagon. Acetylation decreases in parallel the ability of glucagon to stimulate the activity of adenylate cyclase and to bind to its receptors in liver cell membranes of the rat. The biological potencies of the mono, di and tetrasubstituted derivates are, respectively, about 10, 1 and 0.1% that of native glucagon. The binding properties of the material dissociated from the acetylglucagon-receptor complex suggest that the reduction in biological activity results from a decrease in the intrinsic affinity of the modified glucagon for the receptors, as well as from the presence of small amounts of residual, unreacted glucagon. Studies with 125I-labeled derivatives of glucagon indicate that acetylation decreases the rate of association and increases the rate of dissociation of the hormone-receptor complex.
Eur J Biochem 1975 Dec 15
PMID:Acetylglucagon: preparation and characterization. 0 Dec 70

The specificity of thermomycolase toward glucagon and the oxidized A and B chains of insulin was investigated. Extensive digestion of glucagon occurred when conducted at pH 7.0 and 45 degrees C for 40 min, whereas hydrolysis of only three peptide bonds occurred at pH 7.0 and 28 degrees C for 5 min. A similar situation was observed for the oxidized B chain of insulin, which exhibited only a single major cleavage after 5 min at 25 degrees C. No well-defined specificity for particular amino acid residues was evident, but ready hydrolysis of peptide bonds occurred within sequences containing non-polar residues. This endoproteinase must therefore possess an extended hydrophobic binding site for polypeptides. Thermomycolase hydrolysed acetylalanylalanylalanine methyl ester and elastin-Congo Red at 22 and 8.5 times the rate of porcine elastase respectively. A limited degradation of native collagen and significant hydrolysis of benzyloxycarbonyl-Gly-Pro-Leu-Gly-Pro were suggestive of some collagenase-like activity. No keratinase activity was apparent.
Biochem J 1975 Dec
PMID:The substrate specificity of thermomycolase, an extracellular serine proteinase from the thermophilic fungus Malbranchea pulchella var. sulfurea. 0 73

A study of seven patients, each of whom was treated with dopamine within three hours after suffering a myocardial infarction. For four of these, a comparative study was made with isoproterenol, glucagon and ouabaine. The average age of the subjects was 72 years, and all presented considerable myocardial lesions before the treatment was begun. Despite improvement, particularly in diuresis and cardiac output, none of the patients survived. The authors explain these results by the fact that, like all powerful inotropic agents, dopamine produces an increase in oxygen consumption of the myocardium for the ischemic cells situated in the zone contiguous to the infarct.
Ann Anesthesiol Fr 1975 Dec
PMID:[Use of dopamine in the treatment of cardiogenic shock. Preliminary results]. 0 34

After glucagon injection, rats showed virtually identical percentage increases in hepatic histidine-pyruvate aminotransferase and serine-pyruvate aminotransferase activities, both in the mitochondria and in the cytosol. Histidine-pyruvate aminotransferase isoenzyme 1, with pI8.0, was purified to homogeneity from the mitochondrial fraction of liver from glucagon-injected rats. The purified enzyme catalysed transamination between a number of amino acids and pyruvate or phenylpyruvate. For transamination with pyruvate, the activity with serine reached a constant ratio to that with histidine during purification, which was unchanged by a variety of treatments of the purified enzyme. Serine was found to act as a competitive inhibitor of histidine transamination, and histidine of serine transamination. These results suggest that histidine-pyruvate amino-transferase isoenzymes 1 is identical with serine-pyruvate aminotransferase. The enzyme is probably composed of two identical subunits with mol. wt. approx. 38000. The absorbance maximum at 410 nm and the inhibition by carbonyl reagents strongly indicate the presence of pyridoxal phosphate.
Biochem J 1976 Dec 01
PMID:Identity of isoenzyme 1 of histidine-pyruvate aminotransferase with serine-pyruvate aminotransferase. 1 42

The specificity of bovine spleen cathepsin B2 has been investigated by means of some natural oligo- and polypeptides, i.e. glucagon, melittin, insulin A and B chain, bradykinin, angiotensin I and II, oxytocin ACTH, clupein and salmin. The enzyme is primarily a carboxypeptidase which hydrolyzes peptide linkages of most amino acids common to proteins. In addition, cathepsin B2 displays amidase and esterase activity without requiring a free carboxyl group. The main pH optimum is between 4 and 5, in some cases higher.
Biochim Biophys Acta 1976 Dec 08
PMID:On the specificity of bovine spleen cathepsin B2. 1 11

1. Chlorothiazide twice a day plus atenolol, metoprolol, pindolol and propranolol in single daily doses administered to patients with essential hypertension achieved effective control of blood pressure. 2. Each beta-adrenoreceptor-blocking drug was associated with small, but significant, increases in plasma triglyceride concentrations and suppression of fasting immuno-reactive glucagon concentrations.
Clin Sci Mol Med Suppl 1978 Dec
PMID:beta-Adrenoreceptor-blocking agents and lipid metabolism. 3 7

Left ventricular force-generating capacity was determined in 19 anesthetized dogs with heart failure (HF) from aortocaval fistula. At the time of study all dogs had ascites, edema, and elevated pulmonary wedge pressure. Length-contractile force (CF) curves recorded from the left ventricle (LV) with a modified Walton-Brodie arch indicated that the LV was operating on the ascending limb of the length-CF curve at 62.4 +/- 0.1% Lmax in the normal group and in the HF group at 83.4 +/- 2.7% Lmax. In HF the length-CF curve was depressed when compared to normal and was further depressed when CF in grams was normalized for changes in LV wall thickness and expressed as g/cm2. Additionally, dose-response curves of CF in response to injected norepinephrine, isoproterenol, glucagon, and calcium were depressed when compared to the normal group while the response of heart rate and blood pressure was not different. These findings indicate that volume overload HF is associated with depressed ventricular muscle function and a depressed response to inotropic drugs.
Am J Physiol 1978 Dec
PMID:Volume overload heart failure: length-tension curves, and response to beta-agonists, Ca2+, and glucagon. 3 75

Glucagon given as an intravenous injection of 2 mg (0.57 mmol) or as constant intravenous infusion of 1.64 microgram/kg/h (0.47 nmol/kg/h) significantly increased gastric mucosal potential difference (PD) in man. Pentagastrin infusion of 2 microgram/kg/h (2.8 nmol/kg/h) dramatically reduced gastric PD in man. The effect of each of these hormones on PD was reversed by the administration of the other. Changes in PD induced by one hormone were not associated with reductions in blood levels of the other. There was an approximate correlation between changes in PD and pH of gastric aspirates, however, the patterns of PD and pH changes were at times dissimilar. This study indicates that administration of gastrointestinal hormones significantly alters gastric mucosal PD in man.
Gut 1978 Dec
PMID:Effect of glucagon and pentagastrin on gastric mucosal potential difference in man. 3 74

Chick liver cell monolayers synthesize fatty acids at in vivo rates and are responsive to insulin and glucagon. High rates of fatty acid synthesis are maintained with insulin present and lost slowly without insulin. Glucagon or 3',5'-cyclic AMP cause immediate cessation of fatty acid synthesis. The site of inhibition appears to be cytoplasmic acetyl-CoA carboxylase which catalyzes the first committed step of fatty acid synthesis. Liver carboxylase exists either as catalytically inactive protomers or active filamentous polymers. Citrate, an allosteric activator of the enzyme, is required for both catalysis and polymerization. Glucagon and cAMP cause an immediate decrease in the cytoplasmic citrate concentration of chick liver cells apparently by inhibiting the conversion of glucose to citrate at the phosphofructokinase reaction. Since fatty acid synthesis and citrate level are closely correlated, citrate appears to be a feed-forward activator of the carboxylase in vivo. Compelling evidence indicates that carboxylase filaments are present in the intact cell when citrate levels are high and depolymerize when citrate levels fall. Hence, carboxylase activity and fatty acid synthetic rate appear to be determined by cytoplasmic citrate level.
CRC Crit Rev Biochem 1979 Dec
PMID:Hormonal regulation of acetyl-CoA carboxylase activity in the liver cell. 4 83


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