ABSTRACT
The investigation of oxygen radical involvement in a biological system proceeds in different stages. First we study a simple chemical reaction under well defined and controlled conditions in dilute aqueous solutions. This is of course a drastic oversimplification. The second step consists of studying the reaction of these oxygen radicals with biologically important molecules, like proteins, enzymes, fatty acids, and DNA. In the third stage we approach more closely an in vivo situation. Experiments are carried out with whole cells and tissue cultures. The final stage consists of studies involving whole animals or human subjects.
