Forensic Medicine Investigation Into The Changes Of Mast Cell Ultrastructure And Substance P Of Sudden Erethistic Death Guinea Pigs

Objective Guinea pig anaphylactic shock modes were established using heterologous serum. The morphologic changes were observed, and the concentrations of Substance P (SP) in plasma were tested. We are trying to seek objective and sensitive methods to diagnose anaphylactic shock for forensic experts. Method 18 guinea pigs were divided into two groups randomly, the experimental group and the control group, each of which contains 9 guinea pigs. Guinea pigs in the experimental group were made into anaphylactic shock modes with human sera. Plasma, throat, lung, stomach and colon were kept. We did the follow investigations, (1) Levels of SP in plasma were tested using radioimmunologic method; (2) Routine HE staining; (3) SP was stained using immunohistochemical method, and the images of SP were analyzed by BI-2000 image analyzer, and the positive indexes (PI) were calculated; (4) The form of mast cells were observed under transmission electron microscope. Results (1) The concentrations of SP of the experimental group are higher than that of the control group; (2) The specimens of the anaphylactic shock cavies show non-specificity sudden death changes, while the ones of the control group have no obvious changes; (3) Expressions of SP in throat, lung, stomach and colon of the experimental group's cavies are stronger than that in the control group's ones (P＜0.01); (4) Mast cells have released their granules. Conclusion Staining SP and measuring the plasma level of SP, combined with the ultrastructure of mast cell, may be a helpful method to diagnose anaphylactic shock for forensic experts.