Postmortem changes of triazolam concentrations in body tissues

Postmortem changes of triazolam concentrations in body tissues were examined using rats, in order to find the most suitable tissue samples for toxicological analysis. Triazolam was orally given to rats (5 mg/kg), and then the rats were sacrificed 1 hour after administration. Tissue samples were collected 0, 1 and 2 days after storage at 22-24°C, and the triazolam concentration in each sample was measured using gas chromatography with a nitrogen phosphorus detector. Triazolam concentrations were markedly increased in the spleen, the abdominal muscle, the liver and the kidney, and were slightly increased in the blood and the lung. On the other hand, no changes were observed in the thigh muscle or the brain, and the value in the thigh muscle was similar to those in the blood samples collected immediately after death. The results indicate that triazolam diffuses into the surrounding tissues through the stomach wall after death, so that the thigh muscle and the brain have to be analyzed as well as the blood for a correct diagnosis of triazolam ingestion.