仲丁灵原药对大鼠的亚慢性毒性试验

Experiment of the Sub-Chronic Toxicity of Pdibutalin on Rats

目的为了解新型除草剂仲丁灵原药的毒性及其亚慢性毒性的阈作用剂量和最大无作用剂量,并为长期毒性试验提供充分的毒理学资料。方法按照GB 19570-1995的要求进行。每日经口灌胃染毒1次,连续90 d。对照组给予等量2%吐温水溶液。每周用电子称称量大鼠体重。试验前及90 d后进行血液细胞学、血液生化、尿液及病理学检查。各项数据采用SPSS统计软件进行方差分析。结果各染毒组大鼠体重、血液细胞学、血清生化、尿液检查各项指标及脏器系数与对照级比较差异均无显著性。病理组织学检查可见,高剂量组部分动物肝组织出现肝细胞点状坏死,少数肝细胞浊肿,部分汇管区可见慢性炎细胞浸润;睾丸组织结构正常,部分曲细精管明显变薄,管腔增大,各级精母细胞数量变少,精子细胞及成熟精子数量级减少。结论高剂量组部分动物肝组织及睾丸组织出现病理组织学改变,低剂量对大鼠未产生比较明显的毒性作用。初步确定大鼠90 d亚慢性经口最大阈剂量雌、雄大鼠均为625.0 mg/kg,最大无作用剂量,雌、雄大鼠均为312.5 mg/kg。

[ Objective]To explore the sub- chronic toxicity of pdibutalin and the largest ineffective dosage, and provide sufficient toxicolog- ical data for longterm toxicological experiments. [Methods]According to the demand of GB 19570- 1995, the rats were randomly divided into two groups： the toxicant group and the control group. The toxicant group received garaging toxication once per day for 90 constant days. The control group received 2% polysorbate solution of the same dosage. The rats were weighted every week. Haematological, haemabiochemical, urinary and pathological examinations were conducted. [Results]No significant difference was found in the index and ratios of all the examinations. Histopathological examination indicated that the liver tissue of the large - dosage group appeared spotted necrosis. The testis tissue structure was normal with sperm cells and mature sperm amount decreasing. [Conclusion]The liver and testis show pathological changes only in the dosage of 625.0 mg/kg; the maximum ineffective dosage of both female and male rats was 312.5 mg/kg.