Kasten U, Hartwig A, Beyersmann D
Department of Biology and Chemistry, University of Bremen, Federal Republic of Germany.
Arch Toxicol. 1992;66(8):592-7. doi: 10.1007/BF01973391.
V79 Chinese hamster cells were used as a model for the characterization of the Co(II) uptake into mammalian cells as well as the mechanisms involved. Co(II) was taken up in a dose and time dependent manner. The uptake was exponential without saturation in the tested concentration range up to 400 microM CoCl2. Furthermore, there was a high intracellular cobalt accumulation at elevated extracellular Co(II) doses (up to 16 fold at 200 microM). The time course of Co(II) uptake showed a maximum after about 8-12 h with no further change after the longest tested incubation time (24 h). The uptake of Co(II) into V79 cells seems to be mediated by multiple mechanisms: active, energy consuming transport like ion pumps and endocytosis, since the Co(II) uptake was significantly reduced by ouabain (an inhibitor of the Na+/K+ATPase), N-ethylmaleinimide (an inhibitor of the Ca2+/Mg2+ATPase and the Na+/K+ATPase), chlorpromazine (a calmodulin antagonist and inhibitor of the Ca2+/Mg2+ ATPase) as well as by the endocytosis inhibitor chloroquine. Furthermore, the two agents iodoacetate and potassium cyanide, which produce ATP depletion, resulted in a diminution of the intracellular cobalt concentration. An uptake through anion channels could be excluded, since 4,4'-diisothiocyanostilbene-2,2'-disulphonic acid was not inhibitory.
V79中国仓鼠细胞被用作表征钴（II）进入哺乳动物细胞的摄取情况及其相关机制的模型。钴（II）的摄取呈剂量和时间依赖性。在高达400 microM CoCl2的测试浓度范围内，摄取呈指数增长且无饱和现象。此外，在细胞外钴（II）剂量升高时（200 microM时高达16倍），细胞内钴积累量很高。钴（II）摄取的时间进程在约8 - 12小时后达到最大值，在最长测试孵育时间（24小时）后没有进一步变化。钴（II）进入V79细胞的摄取似乎由多种机制介导：主动的、耗能的转运，如离子泵和内吞作用，因为哇巴因（一种Na+/K+ATP酶抑制剂）、N - 乙基马来酰亚胺（一种Ca2+/Mg2+ATP酶和Na+/K+ATP酶抑制剂）、氯丙嗪（一种钙调蛋白拮抗剂和Ca2+/Mg2+ATP酶抑制剂）以及内吞作用抑制剂氯喹均可显著降低钴（II）的摄取。此外，两种导致ATP耗竭的试剂碘乙酸盐和氰化钾会使细胞内钴浓度降低。由于4,4'-二异硫氰基芪-2,2'-二磺酸没有抑制作用，因此可以排除通过阴离子通道的摄取。
