Repair of chromate-induced DNA damage in chick embryo hepatocytes.
Repair of chromate-induced DNA damage in chick embryo hepatocytes.
复制标题
修复鸡胚肝细胞中铬酸盐诱导的 DNA 损伤。
DOI：
10.1093/carcin/5.12.1705
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发表时间：
1984
期刊：
影响因子：
4.7
通讯作者：
Wetterhahn,KE
中科院分区：
文献类型：
--
作者：
Cupo,DY;Wetterhahn,KE
在鸡胚肝细胞中检查了铬酸盐引起的 DNA 损伤的修复。用 5 μM 铬酸钠处理鸡胚肝细胞 2 小时，导致 DNA 链断裂、DNA 链间交联和 DNA-蛋白质交联的形成。 2 小时铬酸盐处理后立即观察到最高水平的链断裂和 DNA 链间交联。去除铬酸盐后，链断裂和 DNA 链间交联分别在 3 小时和 12 小时内完全修复。相比之下，DNA-蛋白质交联继续形成，在铬酸盐去除后 3 小时达到最大水平。尽管 DNA-蛋白质交联水平随后有所下降，但铬酸盐去除后 40 小时仍保持显着水平。通过测量丙异丙基乙酰胺和甲磺酸去铁胺对卟啉积累的诱导（已知这一过程依赖于 mRNA 合成）来检查这些持久的 DNA-蛋白质交联对基因表达的影响。铬酸盐处理 2 小时后，卟啉积累的诱导立即减少。即使在铬酸盐去除后 40 小时，也仅观察到诱导的部分恢复。监测铬酸盐处理对细胞谷胱甘肽水平的影响。用 5 μM 铬酸钠处理 2 小时后，未观察到细胞谷胱甘肽发生变化；然而，去除铬酸盐后 12 小时观察到增加了三倍。
The repair of DNA damage caused by chromate was examined in chick embryo hepatocytes. Treatment of chick embryo hepatocytes with 5 μM sodium chromate for 2 h caused the formation of DNA strand breaks, DNA interstrand crosslinks, and DNA-protein cross-links. The maximal level of strand breaks and DNA interstrand cross-links was observed immediately after the 2 h chromate treatment. After removal of the chromate, strand breaks and DNA interstrand cross-links were completely repaired by 3 h and 12 h, respectively. In contrast, DNA-protein cross-links continued to form reaching a maximal level 3 h after chromate removal. Although the level of DNA-protein cross-links decreased at later times, a significant level persisted 40 h after chromate removal. The effect of these persistent DNA-protein cross-links on gene expression was examined by measuring induction of porphyrin accumulation by propylisopropylacetamide and deferoxamine methanesulphonate, a process known to depend on mRNA synthesis. Induction of porphyrin accumulation was decreased immediately following the 2 h chromate treatment. Only partial recovery of induction was observed even 40 h after chromate removal. The effect of chromate treatment on cellular glutathione levels was monitored. No change in cellular glutathione was observed after a 2 h treatment with 5 μM sodium chromate; however, a three-fold increase was observed 12 h after removal of chromate.