Abstract：
:The widely distributed xanthine oxidoreductase (XOR) system has been shown to be modulated upon exposure of animals to ionizing radiation through the conversion of xanthine dehydrogenase (XDH) into xanthine oxidase (XO). In the present work, radiomodification of the XOR system by phenylmethylsulfonyl fluoride (PMSF) and dithiothreitol (DTT) was examined using female Swiss albino mice which were irradiated with gamma rays at a dose rate 0.023 Gy s(-1). PMSF, a serine protease inhibitor, and DTT, the sulfhydryl reagent, were administered intraperitoneally prior to irradiation. The specific activities of XDH and XO as well as the XDH/XO ratio and the total activity (XDH+XO) were determined in the liver of the mice. The inhibition of XO activity, restoration of XDH activity, and increase in the XDH/XO ratio upon administration of PMSF were suggestive of irreversible conversion of XDH into XO mediated through serine proteases. The biochemical events required for the conversion were probably initiated during the early phase of irradiation, as the treatment with PMSF immediately after irradiation did not have a modulatory effect. Interestingly, DTT was not effective in modulating radiation-induced changes in the XOR system or oxidative damage in the liver of mice. The DTT treatment resulted in inhibition of the release of lactate dehydrogenase. However, the protection appears to be unrelated to the formation of TBARS. On the other hand, the presence of PMSF during irradiation inhibited radiation-induced oxidative damage and radiation-induced increases in the specific activity of lactate dehydrogenase. These findings suggest that a major effect of ionizing radiation is irreversible conversion of xanthine to xanthine oxidase.
journal_name
Radiat Resjournal_title
Radiation researchauthors
Srivastava M,Kale RKdoi
10.1667/0033-7587(2000)154[0094:roxosi]2.0.co;2subject
Has Abstractpub_date
2000-07-01 00:00:00pages
94-103issue
1eissn
0033-7587issn
1938-5404journal_volume
154pub_type
杂志文章abstract：:Whole-body exposure of mice to 2 Gy gamma radiation results in an increase in the specific and total activities of esterase and alkaline phosphatase found in the supernatant of liver and kidney. This increase developed at 1 h, reached a maximum at 24 h, and then declined at 48 h after irradiation. The increase in the ...
journal_title：Radiation research
pub_type： 杂志文章
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更新日期：1987-09-01 00:00:00
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journal_title：Radiation research
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更新日期：1992-11-01 00:00:00
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journal_title：Radiation research
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doi：
更新日期：1987-06-01 00:00:00
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更新日期：2016-06-01 00:00:00
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journal_title：Radiation research
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doi：
更新日期：1990-05-01 00:00:00
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journal_title：Radiation research
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doi：
更新日期：1993-04-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1987-08-01 00:00:00
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pub_type： 杂志文章
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更新日期：1994-05-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1983-03-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1989-03-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14686.1
更新日期：2017-11-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-01-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1990-07-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/RR14655.1
更新日期：2017-06-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：10.1667/0033-7587(2000)154[0326:todiiq]2.0.co;2
更新日期：2000-09-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1988-06-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-12-01 00:00:00
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pub_type： 杂志文章
doi：
更新日期：1991-09-01 00:00:00
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pub_type： 杂志文章,评审
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更新日期：2012-12-01 00:00:00
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pub_type： 杂志文章
doi：
更新日期：1984-11-01 00:00:00
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pub_type： 杂志文章
doi：10.1667/RR13542.1
更新日期：2014-11-01 00:00:00
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pub_type： 杂志文章
doi：
更新日期：1998-01-01 00:00:00
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journal_title：Radiation research
pub_type： 杂志文章
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更新日期：2007-11-01 00:00:00
abstract：:Single crystals of anhydrous inosine were studied subsequent to exposure to high and low doses of X radiation at 10 K using K-band, EPR, ENDOR, and field-swept-ENDOR (FSE) techniques. Immediately following high radiation doses at 10 K at least eight different radicals, RI-RVIII, were observed. All radicals, except for...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1992-05-01 00:00:00
abstract：:The influence of antibiotic decontamination of Pseudomonas contamination of the GI tract prior to whole-body neutron or gamma irradiation was studied. It was observed that for fission neutron doses greater than 5.5 Gy, cyclotron-produced neutron doses greater than 6.7 Gy, and 137Cs gamma-ray doses greater than 14.4 Gy...
journal_title：Radiation research
pub_type： 杂志文章
doi：
更新日期：1985-12-01 00:00:00
abstract：:The objective of this study was to determine whether a deficiency for either one of two repair processes influences the phenomenon of enhancement of radiation-induced cell killing by carboplatin which has been reported previously in one cell line (V79) and which is presumably a result of an interaction between these t...
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doi：
更新日期：1995-11-01 00:00:00
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更新日期：2015-05-01 00:00:00
