Enzyme histochemistry of the liver in autopsy material at different post-mortem times

The authors report the enzyme histochemistry of the liver obtained from autopsy material in 22 corpses (2 to 12 hours post-mortem) and performed to evaluate the sensitivity of enzyme activities to the autolysis process and the use of enzymes to estimate time in forensic pathology. The earliest sample was at 2 hours post-mortem; there was five cases up to 5 hours; eight case up to 8 hours and eight cases up to 12 hours since death. Active phosphorylase (PHYLA a) and total phosphorylase (PHYLA t) were negative two hours after death. PHYLA t reaction represents the activity of PHYLA a increased with the inactive phosphorylase b which can be activated by the addition of ATP and Mg2+ to the incubation medium for phosphorylase a; this activation proved to be ineffective in the post-mortem periods of this study. Glucose-6-phosphatase (G6P-A) also showed a tendency to be sensitive to the autolysis process, displaying a reaction progressively weaker or negative in the post-mortem periods of observation. The results indicate these enzymes as a possible tool to estimate time in forensic pathology deserving further investigation. Lactate dehydrogenase (L-D), alpha-glycerophosphate dehydrogenase (alpha-GP-D) and beta-hydroxybutyrate dehydrogenase (beta-HOB-D) instead showed stronger reactions as the autolysis process evolved.