12-Hydroxyeicosatetraenoic acid (12-HETE) is formed from arachidonic acid either by 12-lipoxygenase or by a cytochrome P450 monooxygenase. 12-Lipoxygenase is generally localized in the soluble cytosolic fraction, and the cytochrome P450 monooxygenase is a microsomal enzyme. In this study, 12-HETE biosynthesis and the regulation of 12-HETE biosynthesis by epidermal growth factor (EGF) in A431 ce...

After force-feeding a protein-free diet to male rats for 5-7 days a substantial (2.4-fold) increase in the specific activity of the liver microsomal enzyme UDP-glucuronyltransferase (EC 2.4.1.17) was observed. A similar activation of the enzyme occurred when rats were fed on a low-protein (5%, w/w, casein) diet for 60 days. Although both the short- and long-term protein-deficient diets decrease...

Antirrhinum majus, Flavonoid Biosynthesis, Flavanone Oxidase, Apigenin, Luteolin Enzyme preparations from flowers of Antirrhinum majus catalysed the oxidation of naringenin to apigenin and of eriodictyol to luteolin. Enzyme activity was found to be localized in the microsomal fraction. The reaction required NADPH as cofactor and had a pH optimum of about 7.0. The NADPH-dependent microsomal enzy...

During analysis of pyruvate kinase distribution in developing guinea-pig liver it was observed that a substantial proportion of the activity remained associated with the microsomal membrane fraction ('microsomes'). Although some of this could be removed by washing with sucrose, the majority required detergent treatment for liberation, and even then at least one-half remained attached to the mic...

Este trabalho analisa o perfil das relações intergovernamentais promovidas pelo Departamento Penitenciário Nacional (DEPEN) para com os governos estaduais entre anos de 2006 a 2016. Partimos da hipótese que foram estabelecidas estratégias distintas em torno criação programas federais e vinculação desses ao repasse recursos financeiros via Fundo (FUNPEN). Por um lado, buscou-se coordenação feder...

The microsomal fraction of sheep vesicular glands has been found to oxygenate 1,3-diphenylisobenzofuran, luminol, and the carcinogenic hydrocarbon benzopyrene when incubated with arachidonic acid. The oxygenations demonstrate an absolute dependence on enzyme and fatty acid and can be completely inhibited by indomethacin and 2,3-dimercaproptopanol, inhibitors of prostaglandin synthetase. The oxy...

Cell fractionation experiments indicate that NAD glycohydrolase (EC 3.2.2.6) is a constituent enzyme of both the microsomal (endoplasmic reticulum) and plasmalemma membrane of the rat hepatocyte. The enzyme was solubilized by steapsin digestion from both fractions and subsequently purified -2000 over the homogenate and -500 over the microsomal fraction by successive DEAE-cellulose, Sephadex G-1...

The effect of enzymatically generated reduced oxygen metabolites on the activity of hepatic microsomal glutathione S-transferase activity was studied to explore possible physiological regulatory mechanisms of the enzyme. Noradrenaline and the microsomal cytochrome P-450-dependent monooxygenase system were used to generate reduced oxygen species. When noradrenaline (greater than 0.1 mM) was incu...

A mouse mast cell tumor microsomal preparation which catalyzes the incorporation of 35S0., from 3’-phosphoadenosine 5’-phosphosulfate-33S into microsomal heparin has been described. This enzyme preparation is the same preparation that previously has been shown to catalyze the incorporation of sugars into a microsomal glycosaminoglycan related to heparin. It is suggested that polysaccharide poly...

Antipyrine has been used as a model drug to investigate the effects of liver disease on drug metabolism in man. A prolongation in antipyrine half-life (T(1/2)) was found in patients with liver disease, patients with chronic liver disease showing a greater increase than those with acute, reversible pathology. The most marked prolongation in T(1/2) was found in association with hypoalbuminaemia a...