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Biomedical subjects

K Kameda

Publications and source records attributed to K Kameda.

At least 145 records · Page 8Linked to original sources
PubMed1980

Chain elongation of trans-octadecenoic acid isomers in rat liver microsomes.

The chain elongations of trans-octadecenoic acid isomers with double-bond positions delta 4 to delta 15 were studied with rat liver microsomes. The delta 7 and delta 9, trans isomers were converted to trans-9 and trans-11-eicosenoic acids, respectively, at about 40% of the rate of conversion of cis-9-octadecenoic acid to cis-11-eicosenoic acid. The rates of conversion of delta 8, delta 10, delta 11, and delta 12 trans isomers were lower than those of delta 7 and delta 9 trans isomers, but the delta 4, delta 5, delta 6, delta 13, delta 14, and delta 15 trans isomers were not elongated at rates exceeding experimental error.

Animals↗
PubMed1979

Participation of superoxide, hydrogen peroxide and hydroxyl radicals in NADPH-cytochrome P-450 reductase-catalyzed peroxidation of methyl linolenate.

1. NADPH-cytochrome P-450 reductase-catalyzed peroxidation of methyl linolenate is inhibited by superoxide dismutase, catalase, ethanol, and mannitol, and is potentiated by H2O2. 2. H2O2 is shown to be generated in the incubation mixture in the presence of NADPH and NADPH-cytochrome P-450 reductase. If the system contains Fe-EDTA complex, H2O2 is not formed. In the presence of the enzyme and Fe-EDTA complex, added H2O2 is consumed. 3. In the presence of Fe-EDTA complex, NADPH-cytochrome P-450 reductase is shown to generate O-2 at a slow rate. These results suggest that H2O2 produced from O-2 is decomposed to form OH . by the action of Fe-EDTA complex in the lipid peroxidation system, and that OH . is a trigger of lipid peroxidation.

Catalase↗
PubMed1977

Effects of dietary vitamin B-2 and vitamin E on the delta9-desaturase and catalase activities in the rat liver microsomes.

The effects of dietary vitamin B-2 and vitamin E on delta9-desaturation of stearoyl-CoA, catalase, glutathione peroxidase, superoxide dismutase and electron transport components in rat liver microsomes have been investigated. delta9-desaturase activities were decreased on diets deficient of vitamin B-2, E and supplemented with E. Among the peroxide-scavenging enzymes, only the catalase activity in microsomes correlates significantly with delta9-desaturase activity. In vitro addition of bovine catalase had no effect on microsomal delta9-desaturase activity on control diet. However, it enhanced the delta9-desaturation in microsomes on vitamin B-2-deficient diet which contained low catalase and high superoxide dismutase activities, compared to those in microsomes of control diet. It is suggested that the hydrogen peroxide-generating and -decomposing systems may play an important role on the delta9-desaturase activity in microsomes.

Animals↗