[Mechanism of cell damage by hematoporphyrin derivative (HPD) plus light. III. Effect of HPD plus light on lysosomes of liver and hepatoma cell].

The effects of HPD plus light on lysosome membrane and release of hydrolysis enzymes from lysosomes of normal rat liver and hepatoma cells were investigated. HPD was bound to lysosome either in vitro or in vivo. Lysosomes bound HPD plus light increased lipid peroxidation of unsaturated fatty acid of lysosome membrane and enhanced the activity of DNase, RNase, cathepsin and acid phosphatase. These effects were related to HPD concentration and exposure time but it was unchanged in the control. It was concluded that the enhancement of hydrolysis enzymes from lysosomes was due to the lysosome membrane damage under the action of siglet oxygen produced by HPD bound lysosomes following light activation.