scholarly journals Guinea-pig liver testosterone 17 β-dehydrogenase (NADP+) and aldehyde reductase exhibit benzene dihydrodiol dehydrogenase activity

1985 ◽  
Vol 225 (1) ◽  
pp. 177-181 ◽  
Author(s):  
A Hara ◽  
M Hayashibara ◽  
T Nakayama ◽  
K Hasebe ◽  
S Usui ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Dehydrogenase Activity ◽  
Aldehyde Reductase ◽  
Pig Liver ◽  
Liver Cytosol ◽  
Dihydrodiol Dehydrogenase ◽  
Guinea Pig Liver ◽  
Oxidation Of Benzene

We have kinetically and immunologically demonstrated that testosterone 17 beta-dehydrogenase (NADP+) isoenzymes (EC 1.1.1.64) and aldehyde reductase (EC 1.1.1.2) from guinea-pig liver catalyse the oxidation of benzene dihydrodiol (trans-1,2-dihydroxycyclohexa-3,5-diene) to catechol. One isoenzyme of testosterone 17 beta-dehydrogenase, which has specificity for 5 beta-androstanes, oxidized benzene dihydrodiol at a 3-fold higher rate than 5 beta-dihydrotestosterone, and showed a more than 4-fold higher affinity for benzene dihydrodiol and Vmax. value than did another isoenzyme, which exhibits specificity for 5 alpha-androstanes, and aldehyde reductase. Immunoprecipitation of guinea-pig liver cytosol with antisera against the testosterone 17 beta-dehydrogenase isoenzymes and aldehyde reductase indicated that most of the benzene dihydrodiol dehydrogenase activity in the tissue is due to testosterone 17 beta-dehydrogenase.

Glutathione peroxidase II of guinea pig liver cytosol: Relationship to glutathione S-transferases

1980 ◽  
Vol 205 (1) ◽  
pp. 122-131 ◽  
Author(s):  
Carl Irwin ◽  
Judy K. O'Brien ◽  
Peter Chu ◽  
Janis K. Townsend-Parchman ◽  
Pat O'Hara ◽  
...  
Keyword(s):  
Glutathione Peroxidase ◽  
Guinea Pig ◽  
Pig Liver ◽  
Liver Cytosol ◽  
Glutathione S Transferases ◽  
Guinea Pig Liver ◽  
Glutathione Peroxidase Ii

(S)-Preferential detoxification of 4-hydroxy-2(E)-nonenal enantiomers by hepatic glutathione S-transferase isoforms in guinea-pigs and rats

2001 ◽  
Vol 355 (1) ◽  
pp. 237-244 ◽  
Author(s):  
Akira HIRATSUKA ◽  
Kouichi TOBITA ◽  
Hiroshi SAITO ◽  
Yasuhiro SAKAMOTO ◽  
Hiroaki NAKANO ◽  
...  
Keyword(s):  
Guinea Pig ◽  
Guinea Pigs ◽  
High Catalytic Activity ◽  
Glutathione S Transferase ◽  
Pig Liver ◽  
Liver Cytosol ◽  
Glutathione S Transferases ◽  
Human Livers ◽  
A Minor ◽  
Guinea Pig Liver

In guinea-pig liver cytosol, racemic 4-hydroxy-2(E)-nonenal (HNE), a reactive and highly toxic product released from biomembranes by lipid peroxidation, was detoxified (S)-preferentially by GSH conjugation mediated by glutathione S-transferases (GSTs) and (R)-preferentially by NAD+-dependent oxidation mediated by aldehyde dehydrogenase (ALDH). The GST-mediated detoxification of the HNE enantiomers proceeded at much higher rates than that mediated by ALDH in guinea-pig liver cytosol. All the major guinea-pig GSTs, A1-1, M1-1, M1-2 and M1-3*, isolated from guinea-pig liver cytosol also catalysed the (S)-preferential conjugation of the HNE enantiomers. The liver and other major tissues of guinea-pigs had no immunologically detectable level of a putative GSTA4-4 orthologue, which exists as a minor GST protein in rat, mouse and human livers and exhibits extremely high catalytic activity towards HNE. All the hepatic rat GSTs, A1-1(2), A1-3, A4-4, M1-1, M1-2 and M2-2, also catalysed the (S)-preferential conjugation of HNE enantiomers.

Phosphatidylinositol movement between isolated microsomal and mitochondrial membranes

1983 ◽  
Vol 61 (12) ◽  
pp. 1282-1291 ◽  
Author(s):  
J. Chudzik ◽  
N. Z. Stanacev
Keyword(s):  
Guinea Pig ◽  
Direct Contact ◽  
Reaction Medium ◽  
Mitochondrial Membranes ◽  
Pig Liver ◽  
Liver Cytosol ◽  
Microsomal Membranes ◽  
Membrane Bound ◽  
Phosphatidylinositol Transfer ◽  
Guinea Pig Liver

Transfer of membrane-bound phosphatidyl-[2′-3H]inositol from microsomal to unlabelled mitochondrial and from mitochondrial to unlabelled microsomal membranes was studied using partially purified cytosol proteins isolated from guinea pig liver cytosol. In the absence and presence of these proteins the amounts of phosphatidylinositol transfer from microsomal to mitochondrial membranes were approximately 21 and 33%, respectively, and the amounts from mitochondrial to microsomal membranes were approximately 31 and 39%, respectively. The release of phosphatidyl-[2′-3H]inositol from microsomal membranes in the absence of mitochondria was dependent on concentration of cytosol proteins. Two mechanisms for movement between membranes are proposed. In cytosol-protein-independent movement of phosphatidyl-[2′-3H]inositol from microsomal to mitochondrial membranes, a direct contact between membranes is required, since phosphatidyl-[2′-3H]inositol was not detected in the reaction medium. In the cytosol-protein-catalyzed transfer, formation of phosphatidyl-[2′-3H]inositol – cytosol protein complex is postulated, since phosphatidyl-[2′-3H]inositol was released into the reaction medium and its movement proceeded from mitochondrial to microsomal membranes in the presence of partially purified cytosol proteins. Thus, contact between the two membranes is probably not necessary for this transfer. Implications for the movement of phospholipids between biological membranes are discussed.

scholarly journals Lipid and steroid hydroperoxides as substrates for the non-selenium-dependent glutathione peroxidase

1979 ◽  
Vol 177 (2) ◽  
pp. 761-763 ◽  
Author(s):  
M R Shreve ◽  
P G Morrissey ◽  
P J O'Brien
Keyword(s):  
Linoleic Acid ◽  
Glutathione Peroxidase ◽  
Guinea Pig ◽  
Glutathione Transferase ◽  
Linoleic Acid Hydroperoxide ◽  
Pig Liver ◽  
Liver Cytosol ◽  
Acid Hydroperoxide ◽  
Guinea Pig Liver ◽  
Rat Liver Cytosol

The reduction of linoleic acid hydroperoxide catalysed by rat liver cytosol was previously shown to be catalysed by a selenium-dependent glutathione peroxidase. In contrast, the enzyme responsible in guinea-pig liver cytosol is not selenium-dependent and appears to be a glutathione transferase.

Die Bedeutung der Homogenisationsart und -intensität für die Größe und Konstanz der Sauerstoffaufnahme von Meerschweinchen-Leberhomogenat / The Influence of Mode and Intensity of Homogenization on the Absolute Value and Stability of Oxygen Consumption of Guinea Pig Liver Homogenates

1977 ◽  
Vol 32 (11-12) ◽  
pp. 908-912 ◽  
Author(s):  
H. J. Schmidt ◽  
U. Schaum ◽  
J. P. Pichotka
Keyword(s):  
Oxygen Uptake ◽  
Guinea Pig ◽  
Measuring Time ◽  
Pig Liver ◽  
Absolute Value ◽  
Modified Method ◽  
Simultaneous Measurements ◽  
Liver Homogenates ◽  
The Absolute ◽  
Guinea Pig Liver

Abstract The influence of five different methods of homogenisation (1. The method according to Potter and Elvehjem, 2. A modification of this method called Potter S, 3. The method of Dounce, 4. Homogenisation by hypersonic waves and 5. Coarce-grained homogenisation with the “Mikro-fleischwolf”) on the absolute value and stability of oxygen uptake of guinea pig liver homogenates has been investigated in simultaneous measurements. All homogenates showed a characteristic fall of oxygen uptake during measuring time (3 hours). The modified method according to Potter and Elvehjem called Potter S showed reproducible results without any influence by homogenisation intensity.

Precision-cut Guinea-pig Liver Slices as a Tool for Studying the Toxicity of Volatile Anaesthetics

1990 ◽  
Vol 18 (1_part_1) ◽  
pp. 191-199
Author(s):  
Hanan N. Ghantous ◽  
Jeanne Fernando ◽  
Scott E. Morgan ◽  
A. Jay Gandolfi ◽  
Klaus Brandel
Keyword(s):  
Guinea Pig ◽  
Rank Order ◽  
Normal Liver ◽  
Liver Slice ◽  
Volatile Anaesthetics ◽  
Pig Liver ◽  
Liver Slices ◽  
Guinea Pig Liver ◽  
Krebs Henseleit Buffer

Cultured precision-cut liver slices retain normal liver architecture and physiological biochemical functions. Hartley male guinea-pig liver slices have proven to be a good model for studying the biotransformation and toxicity of halothane. This system was used to evaluate the biotransformation and toxicity of different volatile anaesthetics (halothane, enflurane, isoflurane and sevoflurane), and compare their effects to those of new anaesthetics (desflurane). Liver slices (250–300μm thick) were incubated in sealed roller vials, containing Krebs Henseleit buffer at 37°C under 95% O2:5% CO2 atmosphere. Volatile anaesthetics were delivered by volatilisation after pre-incubation for 1 hour to produce a constant concentration in the medium. Production of the metabolites, trifluroacetic acid and fluoride ion, was measured. Intracellular potassium ion content, protein synthesis and secretion were determined as indicators of viability of the slices. The rank order of biotransformation of anaesthetics by the liver slices was halothane >sevoflurane>isoflurane and enflurane>desflurane. The rank order of hepatotoxicity of these anaesthetics was halothane>isoflurane and enflurane>sevoflurane and desflurane. Halothane is the anaesthetic which is metabolised furthest and has the most toxic effect, while desflurane is the least metabolised anaesthetic and has the least toxicity. This in vitro cultured precision-cut liver slice system appears to be suitable for studying the biotransformation of volatile anaesthetics and correlating its role in the resulting toxicity.

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