Up and Down 法与寇氏法测定破伤风毒素LD50的比较

摘要

目的 比较研究Up and Down 法与寇氏法测定破伤风毒素LD50值.方法 NIH小鼠皮下注射破伤风毒素,分别使用寇氏法和Up and Down 法计算LD50值.结果同一破伤风毒素经寇氏法计算得LD50值为4.97ng/Kg体重,Up and Down 法计算LD50值为4.93 ng/Kg体重,95%置信区间为(4.71～5.13)ng/Kg体重.结论 应用Up and Down 法可测出与寇氏法相同结果的LD50值,且动物使用数量仅用8只.%Objective To compare the efficacy of Dixon and Mood up-and-down method and Karber method in determining tetanus toxin LD50 in mice. Methods Tetanus toxin in a dose of 0. 5 mL at concentration of 0. 329 , 0. 311 , 0.295, 0.280, 0.267 or 0.256 ng/mL was subcutaneously injected into NIH mice. The LD50 of tetanus toxin was determined by Dixon and Mood up-and-down procedure and Karber test. Results The LD50 of tetanus toxin was 4. 97 ng/ kg body weight measured by Karber method, and 4. 93 ng/Kg body weight by the up-and-down procedure. Conclusions Both Dixon and Mood up-and-down procedure and Karber test can achieve the same LD50 of tetanus toxin, but the up-and-down procedure is more simple and convenient, and 8 animals are enough for this test.