Abstract: Objective To investigate the expression of intercellular adhesion molecule-1(ICAM-1) mRNA in contused skin and muscle of rats and the relationship between the ICAM-1 expression and the wound age. Methods The samples were taken at 0.5, 1, 6, 12, 18, 24 and 30 h after contusion of rats, respectively. Total RNA was extracted both from the skin and muscle samples of each group and reverse transcription polymerase chain reaction (RT-PCR) was conducted to synthesize the 1st strand cDNA. The amount of ICAM -1 mRNA in each sample was quantified using rp132 intrinsic fluorescent assay and compared by the 2(-Delta Delta Ct) method with that from control samples. Results After contusion the expression of ICAM-1 mRNA in skin increased rapidly and peaked at 0.5 h, at 24 h degraded to the amount that was seven times as much as the control group, then rised again. The expression of ICAM-1 mRNA in muscle increased significantly within 0.5 h and peaked at 6 h, reached the minimum at 18 h, then increased again. Conclusion It is suggested that ICAM-1 mRNA analysis may be useful for estimation of early wound age because of its time-related expression after contusion in skin and muscle.

Key words: forensic pathology, contusion, intercellular adhesion molecular, real-time fluorescence quantitative PCR, wound age estimation