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101.
Reduction of tertiary amine N-oxides by liver preparations: function of aldehyde oxidase as a major N-oxide reductase 总被引:1,自引:0,他引:1
Reduction of tertiary amine N-oxides to the corresponding amines by liver preparations was investigated with imipramine N-oxide and cyclobenzaprine N-oxide under anaerobic conditions. Rabbit liver cytosol in the presence of an electron donor of aldehyde oxidase exhibited a significant N-oxide reductase activity which is comparable to the activity of the liver microsomes supplemented with NADPH. Rabbit liver aldehyde oxidase also exhibited the N-oxide reductase activity in the presence of its electron donor, indicating that the activity observed in the liver cytosol is due to this cytosolic enzyme. Furthermore, the tertiary amine N-oxide reductase activity of liver cytosols from rats, mice, hamsters and hogs was demonstrated by comparison with that of liver microsomes from these mammalian species. 相似文献
102.
K. Kitamura C. S. Davies N. C. Nielsen 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1984,68(3):253-257
Summary A cultivar lacking the glycinin subunit A5A4B3 (Raiden) was crossed with one lacking the -subunit of -conglycinin (Keburi). Analysis of F2 and F3 progeny indicated that the missing bands of the A5A4B3 and the -subunit were each controlled by a recessive allele of two independently segregating genes. Gene symbols Gy
4/gy
4 and Cgy
1/cgy
1 were proposed for the genes which confer the presence or absence of the glycinin and conglycinin subunits, respectively.Cooperative research of USDA-ARS and the Indiana Agric. Exp. Stn., Purdue Univ., West Lafayette, IN 47907, USA. Indiana Agric. Exp. Stn. Journal Article 9675. Financial support from the American Soybean Association Research Foundation is gratefully acknowledged 相似文献
103.
Y Tanigawa A Kitamura M Kawamura M Shimoyama K Fujii Y Kohri I Ueda 《Physiological chemistry and physics》1978,10(5):443-448
Administration of prednisolone and cholate to rats elevated levels of cAMP (adenosine 3',5'-cyclic monophosphate) by 1.5- to 2.0-fold. Compounds such as prednisolone, hydrocortisone, cholate, and deoxycholate were found to be potent inhibitors of partially purified cAMP phosphodiesterase prepared from rat liver. Kinetic analysis showed that the prednisolone inhibition was noncompetitive with a Ki of 8.9 x 10(-4) M. These results suggest that in addition to increasing DNA-dependent RNA polymerase activity in vivo, a large application of glucocorticoid may incur elevation of intracellular cAMP levels. 相似文献
104.
The increase in the dichroism of the ester-C=O and COObands in response to mechanical extension in oat coleoptilecell walls was much enhanced by IAA pretreatment while the decreasein that of the C-O-C band was not enhanced or even suppressed.The results indicate the importance of the ultrastructure ofnon-cellulosic polysaccharides in controlling auxin-inducedcell elongation.
1 Present adress: Department of Agricultural Chemistry, KyotoPrefectural University, Shimogamo, Kyoto 606, Japan. (Received May 16, 1978; ) 相似文献
105.
When the dry sperm of the sea urchin, Hemicentrotus pulcherrimus, were diluted 100 times in artificial sea water at 0°C and at 20°C, they became motile and the levels of ATP and creatine phosphate decreased rapidly. The level of ADP hardly changed, and the AMP level increased after the dilution. After the dilution, the respiratory rate at 2°C was almost one fifth that of 20°C. Both phospholipid and glycogen were used for the energy sources in sea urchin sperm. The level of phospholipid was 10-fold higher than that of glycogen in the dry sperm. The phospholipid level decreased after dilution at 20°C, though the level hardly changed at 0°C, suggesting that phospholipid was hardly metabolized the lower temperature. The level of α -glycerophosphate increased at 20°C after the dilution but did not change at 0°C. The level of glycogen decreased after the dilution, regardless of the temperature. The glycolysis was also activated after the dilution. Of the intermediates of the tricarboxylic acid cycle, the citrate concentration increased at 0°C and the malate concentration also increased at 0°C and especially strongly at 20°C. 相似文献
106.
Takahiro Kobayashi Ikuo Morita Sei-Itsu Murota 《Prostaglandins & other lipid mediators》1983,26(2):303-310
Effects of nitrogen dioxide (NO2) exposure on prostacyclin (PGIP2) synthesis in the rat lung and thromboxane A2 (TXA2) synthesis in the platelets were studied. Male Wistar rats were exposed to 10 ppm NO2 for 1, 3, 5, 7 and 14 days. PGI2 synthesizing activity of homogenized lung decreased. The damage of PGI2 synthesizing activity reaches its maximum at 3 days. At 14 days, PGI2 synthesizing activity returned to the normal level. The activity of PGI2 synthetase decreased significantly. The formation of lipid peroxides due to NO2 exposure may cause the depression of PGI2 synthesizing activity of lung. On the other hand, platelet TXA2 synthesizing activity increased. This increased TXA2 synthesizing activity lasted at least till 3 days. Then, it returned to the normal level. The counts of platelet were decreased significantly by 1, 3, 5 and 7 days NO2 exposure. Then the decreased counts of platelet returned to the normal level at 14 days NO2 exposure. These results indicate that the depression of PGI2 synthesizing activity lung by NO2 exposure cause an increase in TXA2 synthesizing activity of platelets. It may contribute to induce platelet aggregation and to the observed decrease in the number of platelets during NO2 exposure. 相似文献
107.
Takehiko Watanabe Yoshitaka Taguchi Yukihiko Kitamura Kenichiro Tsuyama Hirota Fujiki Hiroshi Tanooka Takashi Sugimura 《Biochemical and biophysical research communications》1982,109(2):478-485
The effects of various promoters in two-step carcinogenesis on the induction of histidine decarboxylase in the skin of mice was investigated. The potencies of various phorbol esters in inducing histidine decarboxylase activity were parallel with their tumor-promoting activities. Indole alkaloids such as dihydroteleocidin B and lyngbyatoxin A, which induced ornithine decarboxylase and promoted tumor development in the skin of mice with the same potency as 12-O-tetradecanoylphorbol-13-acetate (TPA), also induced histidine decarboxylase activity. These results suggest that histamine produced by this inducible histidine decarboxylase may play some role in tumor promotion. 相似文献
108.
K Kitamura Y Mizuno A Sasaki A Yasui S Tsuiki K Kikuchi 《Journal of biochemistry》1991,109(2):307-310
A cDNA clone containing the full coding sequence of a type 1 protein phosphatase catalytic subunit 1 alpha has been isolated from a rat kidney lambda gt 10 library. The protein sequence deduced from the cDNA contains 330 amino acid residues with a molecular mass of 38 kDa. The cDNA clone from rat kidney was 89% identical at the nucleotide level in the coding region to type 1 protein phosphatase 1 alpha from rabbit skeletal muscle. However, the two protein sequences were completely identical. The type 1 alpha protein phosphatase from rat kidney shows 49% homology of amino acid sequence to the rat type 2A alpha protein phosphatase. Thus, the protein sequence of type 1 alpha protein phosphatase was completely conserved between rat and rabbit. The mRNA levels of type 1 protein phosphatase were determined in rat liver, AH13, a strain of rat hepatoma, and regenerating rat liver by Northern blot analysis using the cDNA fragment as a probe, under which conditions a single mRNA of 1.5 kb was detected. The mRNA levels of AH13 were remarkably increased when compared to those of normal ivers, whereas the mRNA levels of regenerating livers were slightly but significantly increased. These results demonstrate a marked increase in gene expression of type 1 protein phosphatase in hepatoma cells, suggesting an important role of the type 1 protein phosphatase in hepatocarcinogenesis. 相似文献
109.
Animalizing Effect of A23187 on Sea Urchin Embryos 总被引:4,自引:4,他引:0
Pulse treatment of sea urchin embryos with 3 μM A23187 for 2 hr starting at a stage in initial 10 hr period of development at 20°C, followed by a culture in normal sea water up to the pluteus corresponding stage (45 hr after fertilization), yielded many large exogastrulae with thin embryo walls. The pulse treatment starting at a time between 10 and 13 hr after fertilization yielded considerable number of large prisms and gastrulae having thin embryo walls. Probably, the pulse treatment exerts stimulating effects on ectodermal cell determination in whole span of pre-hatching period to produce animalized embryos. On the other hand, pulse treatment with A23187 in pre-hatching period exerts stage-specific effects on gut formation. Embryos, thus treated for 2 hr starting at stages between 3 and 5 hr after fertilization, produced quite small exoguts but those treated at stages between 7 and 8 hr formed well developed and long exoguts. In embryos treated at the other stages than above, guts or exoguts were almost the same in their size to those in normal ones. These effects of A23187 on morphogenesis were canceled by procaine, tetracaine and ruthenium red. Probably, artificial Ca2+ signal induced by A23187 alters the determination of cell fates, programmed in pre-hatching period. 相似文献
110.