敌枯双对大鼠致畸阈剂量及最大无作用剂量的研究

将60只孕鼠随机地分成A、B、C及D组,前3组于孕笫7～13d分别口服1.0、0.1及0.05mg/kg敌枯双,而D组以0.5％羧甲基纤维素钠对照。每组留3只孕鼠自然分娩,其余者于孕20d处死,检查。发现A及B组畸胎率均非常显著地高于对照组(P<0.005),亦显著高于C组(P<0.025),其子代Fb体重在2.5～3月龄间显著低于F_d(P<0.05)。提出其阈剂量及最大无作用剂量分别为0.1mg/kg及0.05mg/kg。

The Study of TTD and MNEL of N,N’-Methylene-Bis-(2-amino-1,3,4-thiadiazole) (Bis-A-TDA)on the Pregnant Rats

In order to provide scientific basis for maximum permissible concentration (MPC) of Bis-A-TDA in the surface water, the teratogenic threshold dose (TTD) and its maximun no-effect level(MNEL) of Bis-A-TDA on the pregnant rats have been studied. Sixty pregnant rats were divided into A,B,C and D groups at random. Three groups of them were respectively given the dose 1.0, 0.1 and 0.05mg/kg of Bis-A-TDA, but the control group(D)recieved 0.5% sodium carboxy methly fibrin, P.O. from 7th to 18th days during pregnancy. The 3 animals were kept for natural parturation each group and the rest was killed and examined on 20th day. It was found that the incidence of malformation was very significantly higher in the group B than that in the control one (P<0.005), and significantly higher than in group C (P<0.025), and the body-weigh of its offsprings (Fb) was significantly lower than Fd (P<0.05) between 2.5 and 3 months. So we concluded that the TTD of Bis-A-TDA on the pregnant rats is 0.1mg/kg, and MNEL in embryos is 0.05 mg/kg.