Sehlmeyer U, Hechtenberg S, Klyszcz H, Beyersmann D
Institut für Zellbiologie, Biochemie und Biotechnologie, Universität Bremen, Federal Republic of Germany.
Arch Toxicol. 1990;64(6):506-8. doi: 10.1007/BF01977636.
The bioavailability of carcinogenic compounds plays an important role in the process of oncogenesis. Chromium in its hexavalent oxidation state is classified as carcinogen to humans. Therefore we studied the uptake of chromate(VI) into Chinese hamster V79 cells and nuclei isolated after the incubation of the whole cells with chromate. The chromium content of cells and nuclei was determined by atomic absorption spectroscopy. Chromate is taken up in a concentration dependent manner and accumulates to about 30 fold over the extracellular concentration of 0.1 mmol/l. Incubating whole cells with the same concentration results in an intranuclear concentration of up to 6 mmol/l after 3 h. The kinetic parameters (KM = 0.34 mmol/l, Vmax = 0.12 fmol per cell and minute) are in the same order of magnitude as previously published data. The consequences of the high intracellular and intranuclear concentrations are discussed in terms of the genotoxic effects.
致癌化合物的生物利用度在肿瘤发生过程中起着重要作用。六价氧化态的铬被列为对人类的致癌物。因此，我们研究了铬酸盐（VI）被中国仓鼠V79细胞摄取以及全细胞与铬酸盐孵育后分离出的细胞核摄取铬酸盐的情况。通过原子吸收光谱法测定细胞和细胞核中的铬含量。铬酸盐以浓度依赖的方式被摄取，在细胞外浓度为0.1 mmol/l时，其积累量比细胞外浓度高约30倍。用相同浓度孵育全细胞3小时后，细胞核内浓度可达6 mmol/l。动力学参数（KM = 0.34 mmol/l，Vmax = 每个细胞每分钟0.12 fmol）与先前发表的数据处于同一数量级。从遗传毒性效应方面讨论了细胞内和细胞核内高浓度的后果。
