[Distribution of rat embryonal fibroblasts through cell cycle phases in the presence of inhibitors of active oxygen species formation and N-acetylcysteine].

Intracellular level of reactive oxygen species (ROS) and distribution of primary rat embryo fibroblast throughout the cell cycle have been studied. Serum-starved cells were activated by the addition of 10% serum to the culture medium in the presence on N-acetyl-cystein (NAC) and ROS-inhibitors, diphenileniodonium (DPI) and rothenone. It has been shown that serum starvation could block the cells at the G1/S boundary. Activation of serum-starved cells by the addition of serum reactivated the cell cycle and caused cell progression into S phase, which was paralleled with the increase in the intracellular level of ROS. Effects of NAC, PAI and rothenone, similar to that of serum starvation, blocked cell progression into S phase and decreased ROS formation due to the action of serum growth factors. The antiproliferative effect of NAC is discussed.