1.Enhancement of O-dealkylation in Mouse Liver by Dietary Administrations of BHA and BHT: Studies with Isolated Perfused Livers and Hepatic Microsomes.
Sung Chul JI ; James G CONWAY ; Ronald G THURMAN ; Young Nam CHA
Yonsei Medical Journal 1986;27(2):106-113
Effects of feeding 2(3)-tert-butyl 4-hydroxyanisole (BHA) and 3, 5-di-tert-butyl 4-hydroxytoluene (BHT) on the rates of mixed function oxidation and conjugation enzyme reactions have been determined using isolated hepatic microsomal fractions and isolated perfused livers of mice. The treatments with either of the antioxidants have increased the rates of O-demethylation for p-nitroanisole and of O-deethylation for 7-ethoxycoumarin up to 2-fold, both in microsomes and in perfused liver. Analysis of the perfusate showed that the increased amounts of p-nitrophenol and 7-hydroxycoumarin produced by the elevated mixed-function oxidase activities were reflected by the increase in the amounts of glucuronide conjugates and not in the increase for the amounts of the sulfate ester conjugates. Comparison of results also indicated that in the perfused liver, the maximal rate of metabolite conjugation is limited by the maximal rates of the initial mixed function oxidase activities.
Alkylation
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Animal
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Anisoles/metabolism
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Anisoles/pharmacology*
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Butylated Hydroxyanisole/administration & dosage
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Butylated Hydroxyanisole/pharmacology*
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Butylated Hydroxytoluene/administration & dosage
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Butylated Hydroxytoluene/analogs & derivatives*
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Butylated Hydroxytoluene/pharmacology
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Comparative Study
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Coumarins/metabolism
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Female
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Glucuronosyltransferase/metabolism
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Liver/metabolism*
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Mice
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Microsomes, Liver/enzymology
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Microsomes, Liver/metabolism*
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Mixed Function Oxygenases/metabolism
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Oxidation-Reduction
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Perfusion
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Support, U.S. Gov't, P.H.S.
2.The metabolic effects of estriol in female rat liver.
Jin Mo YANG ; Sung Soo KIM ; Jin Il KIM ; Byung Min AHN ; Sang Wook CHOI ; Jae Kwang KIM ; Chang Don LEE ; Kyu Won CHUNG ; Hee Sik SUN ; Doo Ho PARK ; Ronald G THURMAN
Journal of Korean Medical Science 1999;14(3):277-285
The effects of estriol on oxygen uptake, glucose release, lactate and pyruvate production, beta-hydroxybutyrate and acetoacetate production in perfused rat liver as well as, carbon uptake in rat liver and intracellular calcium in isolated Kupffer cells were investigated. Basal oxygen consumption of perfused liver increased significantly in estriol or ethanol-treated rats. But these increased effects were blocked by gadolinium chloride pretreatment. In a metabolic study, pretreatment with estriol resulted in a decrease in glucose production and in glycolysis while an increase in ketogenesis. A more oxidized redox state of the mitochondria was indicated by increased ratios of perfusate [lactate]/[pyruvate] and decreased ratios of perfusate [beta-hydroxybutyrate]/[acetoacetate]. Carbon uptake of Kupffer-cell increased significantly in estriol-treated rats. But these increased uptake were not shown in rats pre-treated by gadolinium chloride blocking phagocytosis. In isolated Kupffer cells from estriol-treated rats, intracellular calcium was more significantly increased after addition of lipopolysaccharide (LPS) than in controls. These findings suggest that the metabolic effects of estriol (two mg per 100 mg body wt) can be summarized to be highly toxic in rat liver, and these findings suggest that oral administration of estrogens may induce hepatic dysfunctions and play a role in the development of liver disease.
3-Hydroxybutyric Acid/metabolism
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Acetoacetates/metabolism
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Animal
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Calcium/metabolism
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Carbohydrates/metabolism
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Carbon/metabolism
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Cells, Cultured
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Colloids/metabolism
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Estriol/pharmacology*
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Estriol/metabolism
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Ethanol/pharmacology
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Female
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Gadolinium/pharmacology
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Glucose/biosynthesis
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Intracellular Fluid/metabolism
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Kupffer Cells/metabolism
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Kupffer Cells/cytology
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Lactates/metabolism
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Lipids/metabolism
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Liver/metabolism
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Liver/drug effects*
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Oxygen Consumption
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Phagocytosis
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Pyruvic Acid/metabolism
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Rats
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Rats, Sprague-Dawley