Fukami M H, Flatmark T
Biochim Biophys Acta. 1986 Oct 31;889(1):91-4. doi: 10.1016/0167-4889(86)90012-1.
The cellular compartmentation of catalase was studied in digitonin-permeabilized rat hepatocytes. A biphasic dose-response curve was observed for the unmasking of catalase activity by digitonin in latency studies. About 40-60% of the total catalase activity was seen in the range of 5-200 microM digitonin compared to 13% free activity in control preparations without digitonin. The free catalase activity began to increase again above 300 micron digitonin, and all latency was lost around 500 microM and above. These results indicate that there exists in rat hepatocytes catalase with two levels of crypticity to digitonin, only one of which was seen in a mixed organelle preparation containing peroxisomes.
在洋地黄皂苷通透处理的大鼠肝细胞中研究了过氧化氢酶的细胞区室化。在潜伏期研究中，观察到洋地黄皂苷使过氧化氢酶活性去掩盖呈现双相剂量反应曲线。与无洋地黄皂苷的对照制剂中13%的游离活性相比，在5-200微摩尔洋地黄皂苷范围内可见约40-60%的总过氧化氢酶活性。洋地黄皂苷浓度高于300微摩尔时，游离过氧化氢酶活性又开始增加，在500微摩尔及以上时所有潜伏期消失。这些结果表明，大鼠肝细胞中存在对洋地黄皂苷具有两种隐匿水平的过氧化氢酶，其中只有一种在含有过氧化物酶体的混合细胞器制剂中可见。
