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Cisplatin-resistant cells, Pt4 and Pt8 cells, were obtainedom
Chinese hamster ovary (CHO-K1) cells after long-term
culturecisplatin containing medium. Pt8 cells were about
1.3-foldesistant to cadmium chloride (CdCl2) than CHO-K1 cells.
SH content in Pt4 cells was 1.3-fold more than that in4 cells
were about 2.9-fold more sensitive to CdCl2after examination
with clonogenic survival.20 uM of CdCl2, Pt4 cells were induced
aboutmicronucleus than K1 cells were. But Pt8 cellsss
micronucleus (about 0.9-fold) than K1 cells were. From nuclear
division index, nuclear division in4 cells was inhibited more
than that in K1 cells was. Theite results were observed in
Pt8 cells (CdCl2 concentration50: K1=20 uM; Pt4=11 uM; Pt8=21.5
uM). In addition,from nucleoid sedimantation assay indicated
that the DNAon was significant changed in Pt4 cells after
highns of CdCl2 exposure. Also, K1 cells recovered by time
dependence after incubatedth fresh medium for 4 or 8 h when
treated with CdCl2 for 2 h.Pt4 cells did not recover for 4 or 8
h when treated withfor 2 h. So it seems that Pt4 cells did not
recover damagediciently. The detoxfied enzymes, such as
catalase,ne S-transferase, and heme oxygenase were nottly
different in K1, Pt4 and Pt8 cells. These suggestls were more
resistant than K1 cells after exposedmore GSH contents, and Pt4
cells were moreK1 cells after CdCl2 exposure for less
reapirmore cadmium accumulation.
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