Abstract: Objective To increase the death rate of fatal anaphylaxis in guinea pigs and the detectable level of the tryptase of mast cell in blood serum. Methods Seventy-four guinea pigs were randomly divided into five groups： original model group, original model control group, improved model group, improved model control group, improved model with non-anaphylaxis group. Using mixed human serum as the allergen, the way of injection, sensitization and induction were improved. ELISA was used to detect the serum mast cell tryptase and total IgE in guinea pigs of each group. Results The death rate of fatal anaphylaxis in original model group was 54.2% with the different degree of hemopericardium. The severe pericardial tamponade appeared in 9 guinea pigs in original model group and original model control group. The death rate of fatal anaphylaxis in improved model group was 75% without pericardial tamponade. The concentration of the serum total IgE showed no statistically difference between original model group and original model control group（P>0.05）, but the serum mast cell tryptase level was higher in the original model group than that in the original model control group （P<0.05）. The concentration of the serum total IgE and the serum mast cell tryptase level were significantly higher in improved model group than that in the improved model control group （P<0.05）. Conclusion The death rate of the improved model significantly increases, which can provide effective animal model for the study of serum total IgE and mast cell tryptase.

Key words: forensic pathology, anaphylaxis, models, animal, guinea pigs