甲胺磷对小鼠的行为致畸

实验选用多项行为检测指标及定量组织学方法,以对硫咪唑为阳性对照,研究了有机磷农药甲胺磷的小鼠行为致畸效应。结果表明小鼠围产期接触对硫咪唑和低剂量甲胺磷影响其仔代的躯体发育、反射发育及学习能力,并导致大脑皮质神经元密度增加。

Behavioral toxicity in the offspring of mice following maternal exposure to mathamidophos

Previous studies have demonstrated that methamidophos markedly inhibited ChE activity in rat brain. Developmental retardation in rats produced by in utero exposure to methamidophos was also reported. This study was designed to examine the effects of perinatal methamidophos exposure in mice at lower dose levels (1/6 LD50-1/60 LD50) on the development of behaviour and cerebral cortex in their off spring. Methamidophos 0,0.4, 2.2 and 4mg/ (kg·d) were given to adult Kunming female mice from the 16 th gestation day to the 21 th postnatal day (the weaning day of the offspring) with feeding needles. A positive control group exposed to an antithyroid drug, methimazole (100 mg/ (kg·d) at the same time. The offsprings were assessed on a series of tests referring to the Cincinnatipsychoteratogenicity screening test battery. Differences between methamidophos (2.2,4 mg/ kg) and normal control group were observed in gestation length, eye opening, surface righting, auditory startle, reflex suspension, swimming development, T-water maze and neuron density in cerebral cortex. Treatment with 0.4 mg/kg methamidophos significantly delayed auditory startle and swimming ability development, shortened the time of reflex suspension and lowered T-water maze learning abilities of the offspring. The results showed that methamidophos produced evidence of both physical and behavioral toxicity in developing mice at lower dose levels.