抄録
Membrane-bound glutathione S-transferase (MGST1) is abundantly distributed in microsomes and mitochondria (MT) of rat liver. In our laboratory it has been demonstrated that microsomal MGST1 is activated by reactive oxygen species (ROS) and heating. Since mitochondria are important role for ROS generation in oxidative stress, we examined whether MT-MGST1 is activated by ROS generated within mitochondria. MT was prepared after perfusion of the liver with 1.15% KCl containing benzamidine from non-treated S.D. rats. When MT was incubated with substrates for the respiration chain, ROS (hydroxyl radical) was detected by ESR spectrometer and MT-MGST1 activity was increased 2-fold. MT-ROS generation was increased with incubation temperature whereas MGST1 activity was decreased at 55 oC in spite of large amount of ROS generation. These results suggest that MT-MGST1 is regulated by ROS generated in MT.
