Effects of photosensitized and ionizing irradiation on the activity of antioxidant and phase II enzymes in Ehrlich ascites cells

Abstract

Hematoporphyrin dimethyl ester (Hpde)-sensitized photoirradiation of Ehrlich ascites cells or their ionizing irradiation (2 Gy) in the presence or absente of Hpde insignificantly influenced the activity of the antioxidant enzymes catalase, superoxide dismutase and glutathione reductase determined 2 h after irradiation. The above procedures as well as Hpde in the dark decreased the activities of the phase II enzymes glutathione-S-transferase and DT-diaphorase. The possible significance of these phenomena in combined tumour therapy is discussed. Keywords: photosensitization, ionizing irradiation, catalase, superoxide dismutase, glutathione reductase, glutathione-S-transferase, DT-diaphorase