Abstract: Objective To determine the electrical conductivity （EC） of the liver, spleen and kidney of rats at different postmortem intervals （PMIs） within 24 hours for investigating the relationship between EC of different organs and early PMI. Methods Totally 45 SD rats were sacrificed by cervical dislocation and kept at a constant temperature of 25 ℃. Tissues were taken from the liver, spleen, and kidney of rats at 0, 3, 6, 9, 12, 15, 18, 21 and 24 h. Impregnating solution with a mass concentration 0.1 g/mL was prepared using deionized water. The EC value of impregnating solution with different organs was separately determined. The regression equations of EC and PMI for different organs were established, respectively. The relationship between EC of different organs and early PMI was analysed in deceased rats. Results The relationship between PMI and EC of the liver and spleen was well fitted with the linear equation. The liver showed the best fitting degree followed by the spleen, while the EC of the kidney showed no significant changes within 24 h. There was a good linear relationship between early PMI and the EC of the liver and spleen. Conclusion A good linear relationship between early PMI and the EC of the liver and spleen can be found in rats after death, which can be used for the early PMI estimation.

Key words: forensic pathology, postmortem interval, electrical conductivity, liver, spleen, kidney, rats