Electron spin resonance studies of free radicals in gamma-irradiated golden hamster embryo cells: radical formation at 77 and 295 K, and radioprotective effects of vitamin C at 295 K.
Electron spin resonance studies of free radicals in gamma-irradiated golden hamster embryo cells: radical formation at 77 and 295 K, and radioprotective effects of vitamin C at 295 K.
复制标题
伽马射线照射的金仓鼠胚胎细胞中自由基的电子自旋共振研究：77 和 295 K 下的自由基形成，以及 295 K 下维生素 C 的辐射防护作用。
DOI：
10.2307/3578548
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发表时间：
1993
影响因子：
3.4
通讯作者：
M. Watanabe
中科院分区：
文献类型：
--
作者：
T. Yoshimura;K. Matsuno;T. Miyazaki;K. Suzuki;M. Watanabe
用电子自旋共振（ESR）光谱法研究了77和295 K γ辐射对金仓鼠胚胎（GHE）细胞自由基形成的影响。在8gy ~ 1.3 kGy范围内，77 K γ辐照冷冻细胞的自由基产率随剂量的增加呈线性增加，表明8gy剂量下自由基的形成机制与1.3 kGy剂量下相同。在295 K下用5 kGy伽马射线照射GHE细胞，然后在77 K下测量ESR谱，可以清楚地观察到部分产生的有机自由基。在室温下，有机自由基在GHE细胞中存活24小时以上。在向GHE细胞中添加维生素C后，伽马辐射形成的有机自由基受到抑制。当白蛋白水溶液（0.1 kg dm-3）在295 K下以5 kGy辐照时，用ESR观察到白蛋白自由基。添加维生素C后，白蛋白自由基的形成被显著抑制。维生素C对自由基形成的有效辐射防护被解释为维生素C清除白蛋白自由基。
Formation of free radicals in golden hamster embryo (GHE) cells produced by gamma irradiation at 77 and 295 K has been studied by electron spin resonance (ESR) spectroscopy. The yields of free radicals in the gamma-irradiated frozen cells at 77 K increase linearly with increasing dose in the range from 8 Gy to 1.3 kGy, suggesting that the mechanism of radical formation at a dose of 8 Gy is the same as that at 1.3 kGy. When GHE cells are irradiated with 5 kGy gamma rays at 295 K and then the ESR spectrum is measured at 77 K, a part of the organic radicals produced can be observed clearly. The organic radicals survive in GHE cells for more than 24 h at room temperature. The formation of the organic radicals by gamma irradiation is suppressed upon the addition of vitamin C to the GHE cells. When an aqueous solution of albumin (0.1 kg dm-3) is gamma-irradiated with 5 kGy at 295 K, albumin radicals are observed by ESR. The formation of the albumin radicals is suppressed drastically upon the addition of vitamin C. The efficient radioprotection of vitamin C against radical formation has been interpreted in terms of the scavenging of albumin radicals by vitamin C.