Hematoporphyrin-sensitized photodamage of alkaline phosphatase and lactate dehydrogenase in Yoshida hepatoma cells

Alkaline phosphatase and lactate dehydrogenase activities are inhibited by hematoporphyrin (HP) bound to live Yoshida hepatoma cells in the dark and, to a higher extent, upon illumination. The mechanistic implications of this observation are discussed and the proposal to investigate marker enzymes as sensitive probes of cell photodamage is presented.