School of Public Health, Central South University, Changsha Hunan, China.
Braz J Med Biol Res. 2012 Jun;45(6):482-7. doi: 10.1590/s0100-879x2012007500040. Epub 2012 Mar 22.
This study explored the reduction of adenosine triphosphate (ATP) levels in L-02 hepatocytes by hexavalent chromium (Cr(VI)) using chi-square analysis. Cells were treated with 2, 4, 8, 16, or 32 μM Cr(VI) for 12, 24, or 36 h. Methyl thiazolyl tetrazolium (MTT) experiments and measurements of intracellular ATP levels were performed by spectrophotometry or bioluminescence assays following Cr(VI) treatment. The chi-square test was used to determine the difference between cell survival rate and ATP levels. For the chi-square analysis, the results of the MTT or ATP experiments were transformed into a relative ratio with respect to the control (%). The relative ATP levels increased at 12 h, decreased at 24 h, and increased slightly again at 36 h following 4, 8, 16, 32 μM Cr(VI) treatment, corresponding to a "V-shaped" curve. Furthermore, the results of the chi-square analysis demonstrated a significant difference of the ATP level in the 32-μM Cr(VI) group (P < 0.05). The results suggest that the chi-square test can be applied to analyze the interference effects of Cr(VI) on ATP levels in L-02 hepatocytes. The decreased ATP levels at 24 h indicated disruption of mitochondrial energy metabolism and the slight increase of ATP levels at 36 h indicated partial recovery of mitochondrial function or activated glycolysis in L-02 hepatocytes.
本研究通过卡方分析探讨了六价铬（Cr(VI)）对 L-02 肝细胞中三磷酸腺苷（ATP）水平的降低作用。细胞用 2、4、8、16 或 32 μM Cr(VI) 处理 12、24 或 36 h。用噻唑蓝（MTT）实验和分光光度法或生物发光法测定细胞内 ATP 水平，分别在 Cr(VI)处理后进行。卡方检验用于确定细胞存活率和 ATP 水平之间的差异。对于卡方分析，MTT 或 ATP 实验的结果转化为与对照（%）的相对比值。4、8、16、32 μM Cr(VI) 处理 12 h 后相对 ATP 水平升高，24 h 后降低，36 h 后略有升高，呈“V 形”曲线。此外，卡方分析的结果表明，32 μM Cr(VI) 组的 ATP 水平差异具有统计学意义（P < 0.05）。结果表明，卡方检验可用于分析 Cr(VI)对 L-02 肝细胞中 ATP 水平的干扰作用。24 h 时 ATP 水平降低表明线粒体能量代谢受到破坏，36 h 时 ATP 水平略有升高表明 L-02 肝细胞中线粒体功能部分恢复或糖酵解激活。
