Subcellular localization of glutathione and thermal sensitivity.
Subcellular localization of glutathione and thermal sensitivity.
复制标题
DOI：
10.2307/3577295
复制
发表时间：
1988-09
影响因子：
3.4
通讯作者：
Michael L. Freeman;M. Meredith
中科院分区：
文献类型：
--
作者：
Michael L. Freeman;M. Meredith
在42 ℃孵育期间，将中国仓鼠卵巢（CHO）细胞暴露于不同浓度的马来酸二乙酯（DEM），以确定谷胱甘肽（GSH）区室化是否是热敏性改变的一个因素。在42 ℃下加热处理2小时后，立即从CHO细胞中分离细胞质和线粒体GSH。在这些实验条件下，观察到细胞质和线粒体室之间的差异GSH耗尽。例如，需要12 μ M DEM才能将细胞质GSH消耗50%，而将线粒体GSH消耗到相同水平需要24 μ M DEM。此外，相对胞质GSH浓度与DEM浓度的ln-ln图显示线性关系（斜率= -1.0）。相比之下，线粒体GSH图显示出肩部，随后是线性去除（斜率= -0.90）。这两条直线基本上是平行的。暴露于10和100 μ M之间的DEM的细胞的热剂量-反应曲线的分析表明，细胞的存活率不受DEM的加入，直到超过一个临界浓度。这种阈值反应被解释为意味着线粒体GSH耗竭是限制因素。
Chinese hamster ovary (CHO) cells were exposed to various concentrations of diethylmaleate (DEM) during a 42 degrees C incubation to determine if glutathione (GSH) compartmentalization was a factor in modification of thermal sensitivity. Cytoplasmic and mitochondrial GSH were isolated from CHO cells immediately after a hyperthermic treatment consisting of 2 h at 42 degrees C. Under these experimental conditions differential GSH depletion between the cytosol and mitochondrial compartments were observed. For example, 12 microM DEM was needed to deplete cytoplasmic GSH by 50% compared to 24 microM DEM needed to deplete mitochondrial GSH to the same level. Further, an ln-ln plot of the relative cytosolic GSH concentration vs the DEM concentration indicated a linear relationship (slope = -1.0). In contrast, the mitochondrial GSH plot exhibited a shoulder followed by a linear removal (slope = -0.90). Essentially the two linear curves were parallel. Analysis of thermal dose-response curves for cells exposed to between 10 and 100 microM DEM indicated that cell survival was unaffected by the addition of DEM until a critical concentration was surpassed. This threshold response was interpreted to mean that mitochondrial GSH depletion was the limiting factor.