中文摘要：

目的评价氯胺酮的线粒体毒性,从而探讨氯胺酮可能的毒性机制。方法 Hep G2细胞培养基中分别加入齐多夫定10~2000μmol·L-1培养7 d,或加入氯胺酮50~3000μmol·L-1培养24 h,CCK8细胞计数法测定细胞存活率。Hep G2细胞培养基中分别加入齐多夫定100μmol·L-1培养7 d后,或加入氯胺酮100和1200μmol·L-1培养24 h,化学发光法检测胞内ATP合成水平,荧光探针法检测胞内钙离子浓度、活性氧及线粒体膜电位（ΔΨm）的变化,同时设齐多夫定1000μmol·L-1用于实时荧光定量PCR检测线粒体DNA（mt DNA）表达水平的变化。结果与正常对照组相比,齐多夫定10~2000μmol·L-1可以抑制细胞存活,IC50为100μmol·L-1;氯胺酮1000~3000μmol·L-1抑制细胞存活,IC50为1200μmol·L-1。与正常对照组相比,齐多夫定100μmol·L-1组线粒体ATP合成水平显著下降（P〈0.05）,胞内钙离子浓度明显升高（P〈0.05）,活性氧水平显著升高（P〈0.05）,ΔΨm显著下降（P〈0.05）,而1000μmol·L-1可以明显干扰mt DNA表达水平（P〈0.05）。氯胺酮100μmol·L-1组ATP合成水平明显下降（P〈0.05）,其他指标均无显著性差异;氯胺酮1200μmol·L-1组ATP合成水平显著下降（P〈0.01）,活性氧水平和胞内钙离子浓度显著升高（P〈0.01）,ΔΨm显著下降（P〈0.05）,mt DNA水平无明显改变。结论氯胺酮可以通过干扰线粒体代谢功能而诱导线粒体损伤。

英文摘要：

OBJECTIVE To evaluate the potential mitochondrial toxicity of ketamine and to explore its mechanisms. METHODS Hep G2 cells were cultured in zidovudine（ AZT） 10- 2000 μmol·L- 1for 7d or ketamine 50- 3000 μmol·L- 1for 24 h. The cell viability was assessed by CCK8 assay. Hep G2 cells were cultured with AZT 100 μmol·L- 1for 7 d or ketamine 100 and 1200 μmol·L- 1for 24 h. The levels of cellular ATP were detected by luciferase assay. The levels of reactive oxygen species（ ROS）,intracellular free Ca2 ＋,and mitochondrial membrane potential（ Δψm） were determined by flow cytometry.Hep G2 cells were cultured with AZT 100 and 1000 μmol·L- 1for 7 d or ketamine 100 and 1200 μmol·L- 1for 24 h while the content of mt DNA was quantified by RT-PCR. RESULTS Compared with normal group,AZT at 10- 2000 μmol·L- 1markedly inhibited cell viability（ IC50= 100 μmol·L- 1）,so did ketamine at 1000- 3000 μmol·L- 1（ IC50= 1200 μmol·L- 1）. After AZT 100 μmol·L- 1treatment,compared with normal Hep G2 cells,ATP levels were significantly decreased（ P 0. 05） while the level of ROS and intracellular free Ca2 ＋significantly increased（ P 0. 05）. Δψmobviously decreased,but no significant changes in mt DNA content were observed,although a 0. 6-fold decrease in mt DNA content was observed at the concentration of AZT 1000 μmol·L- 1（ P 0. 05）. Ketamine 100 μmol·L- 1significantly decreased cellular ATP levels（ P 0. 05）,but there was no significant difference in other parameters.Ketamine 1200 μmol·L- 1significantly decreased cellular ATP levels（ P 0. 01）,but significantly increased ROS levels（ P 0. 01） and intracellular Ca2 ＋levels（ P 0. 01） while significantly decreasingΔψm（ P 0. 05）. No change in mt DNA content was observed. CONCLUSION Ketamine can induce mitochondrial toxicity by interfering with mitochondrial metabolism.