Comparison of the toxicity of APBMV and its composition AP-III

Aim:In order to apply antineoplastic polypeptide from Buthus Martensii venom(APBMV) and antineoplastic polypeptide Ⅲ from APBMV(AP Ⅲ) to clinical treatment at maximum safe degree, and to evaluate the toxicosis medicinalis and side effect. Methods: 120 mice(20～22 g) were divided at random into 12 groups(10 mice/group), and injected by ip with APBMV(Group1～6) or AP Ⅲ(Group7～12) in 0.2 ml/20 g of different concentrations. The conduct and pathological changes in organs of animals were observed after drug injected.The LD 50 and L 95 of APBMV or AP Ⅲ were evaluated with the method of complex count. Results: 1～5 min after injecting APBMV or AP Ⅲ in higher concentration, the changes of animal behaviours were found from screaming, jumping, lapping the injected position, slobbering to irregular breath. With the prolongation of survival time, the animals were quiescent, spastic paralystic, breathed quickly, stifled, and were convulsive until dead. Most animals were dead in 90 min after injection and then anatomized. The pathological change was not found by naked eye in important internal organs of dead animals. According to the drug and dead rate, the LD 50 of APBMV was 9.738 mg/kg and L 95 was from 8.211 mg/kg to 11.265 mg/kg,the LD 50 of AP Ⅲ was 8.17 mg/kg and L 95 was from 6.898 mg/kg to 9.456 mg/kg. Conclusion: The LD 50 of AP Ⅲ is lower than APBMV’s, which means the acute toxicity of the former is higher than that of the latter.