POSSIBLE MARKERS FOR POSTMORTEM DRUG REDISTRIBUTION

The possibility that postmortem biochemical changes in blood might par allel drug redistribution and thus serve as markers was explored in a detailed case study. Eighteen blood and 14 tissue and fluid samples we re taken at autopsy 16 h after the death of a 34-year-old female from amitriptyline overdose. Ranges of drug concentrations in blood were am itriptyline 1.8 to 20.2 mu g/mL, nortriptyline 0.6 to 7.3 mu g/mL, lev els were lowest in femoral vein and highest in pulmonary vein blood. C orresponding levels of 17 amino acids showed markedly different patter ns of site-to-site variability. There was a strong positive correlatio n between individual amino acid and drug concentrations in pulmonary b lood samples (n = 5), particularly for glycine, leucine, methionine, s erine, and valine. In blood samples from the great veins and right hea rt (n = 10), the correlation was less strong (r = 0.6 to 0.7). Methion ine showed a strong positive correlation in pulmonary samples (r = 0.9 3), and negative correlation in great veing samples (r = -0.68). Lacti c acid showed a strong negative correlation in pulmonary samples (r = -0.93) but a positive correlation in great vein samples (r = 0.71). Al anine aminotransferase, alkaline phosphatase, aspartate aminotransfera se, gamma-glutamyl transferase, glucose, and bilirubin had a weak posi tive correlation with drug levels in great vein samples but not pulmon ary samples. The results suggest that hepatic enzymes are relatively p oor markers for postmortem hepatic drug shifts but that amino acids, p articularly methionine, may be useful markers for pulmonary drug shift s.