Woźniak K
Katedra Genetyki Molekularnej Uniwersytetu Lódzkiego.
Postepy Hig Med Dosw. 1996;50(4):383-94.
Chromium(VI) compounds produce a variety of DNA damage such as DNA single strand breaks, alkali-labile sites and DNA-protein cross-links in vivo and in cultured cells. Chromium(III) compounds bound to isolated DNA and proteins. Cr(VI) readily entered cell through general anion channels. In contrast, Cr(III) did not readily cross cell membranes. Inside cells Cr(VI) is reduced through intermediates to Cr(III) by cellular reductants. Reactive intermediates formed during intracellular Cr(VI) reduction might be responsible for some chromate genotoxicity. Ascorbic acid decreases chromate induced alkali-labile sites and chromium inhibition of glutathione reductase, but it enhances DNA-protein cross-links and cytotoxicity caused by this metal.
六价铬化合物在体内和培养细胞中会产生多种DNA损伤，如DNA单链断裂、碱不稳定位点和DNA-蛋白质交联。三价铬化合物可与分离出的DNA和蛋白质结合。六价铬通过一般阴离子通道很容易进入细胞。相比之下，三价铬不容易穿过细胞膜。在细胞内，六价铬通过细胞还原剂经中间体还原为三价铬。细胞内六价铬还原过程中形成的活性中间体可能是某些铬酸盐遗传毒性的原因。抗坏血酸可减少铬酸盐诱导的碱不稳定位点以及铬对谷胱甘肽还原酶的抑制作用，但会增强这种金属引起的DNA-蛋白质交联和细胞毒性。
