[Characteristics of the activation of lysosomal enzymes in the rat liver after death and during resuscitation].

Alterations in activity of lysosomal acid phosphatase and cathepsin D, as well as of hepatocyte ultrastructure were studied in rat liver tissue after experimental heart arrest within 10 and 30 min and during the early post-resuscitation period. Cathepsin D free activity in a supernatant fraction as well as both enzymatic activities in lysosomal fraction were increased after 30 min heart arrest. Activity of acid phosphatase and cathepsin D in lysosomes was decreased, while the activity of the free enzymes was increased within 1 and 4 hrs after resuscitation. Triton X-100 (0.025%) caused labilization of lysosomal membranes. Alterations in ultrastructure of hepatocytes were observed within 30 min of the heart arrest and within first hour of the post-resuscitation period. The lysosomal membranes tended to normalization within 24 hrs after the post-resuscitation period, whereas the enzymatic activity remained elevated. Role of lysosomes in regulation of intracellular metabolism is discussed.