Abstract: Objective To study the expression of substance P (SP) in human sudden erethistic death, and to seek objective morphological supports to diagnose sudden erethistic death for forensic medicine. Methods The expression of SP was detected with immunohistochemical technique on 15 human laryngopharynx and gastrointestine of sudden erethistic death, and 20 sudden death of heart attack as control. The images of SP were analyzed by image analyzer, and the positive indexes(PI) were calculated. Results SP expression in the experimental groups was significantly stronger than that in the control one (P<0.001). Conclusion SP expression can offer an objective morphological reference support for forensic diagnosing sudden erethistic death.

Key words: substance P, sudden erethistic death, immunohistochemistry