低剂量镉预处理对高剂量镉致胎鼠畸形作用的影响

Influence of low dose cadmium pretreatment on teratogenic effect of fetal rats induced by high dose cadmium

目的观察低剂量镉预处理是否对较高剂量镉对胎鼠的致畸作用存在拮抗作用,为环境中镉浓度控制提供依据。方法采用随机区组法将60只Sprague-Dawley孕鼠分为4组,即对照组、实验1组(0.06 mg·kg-1Cd2+组)、实验2组(0.06 mg·kg-1+5.00 mg·kg-1Cd2+组)、实验3组(5.00 mg·kg-1Cd2+组),每组15只。采用腹腔注射法染毒,每天测体质量,孕19 d颈椎脱臼处死孕鼠,剖腹检查子宫、卵巢形态,分别记录活胎数、吸收胎和死胎数,测活胎体质量、颅尾长和尾长,观察活胎外形。结果实验2组和实验3组部分孕鼠卵巢出现积液和出血。实验2组、实验3组的吸收胎率和死胎率均高于对照组和实验1组,窝均体质量均低于对照组和实验1组(P<0.05);实验2组死胎率和吸收胎率低于实验3组(P<0.05),窝均体质量高于实验3组(P<0.05);各组的肋骨畸形分布情况差异有统计学意义(P<0.05)。结论腹腔注射0.06 mg·kg-1的镉预处理可在一定程度上拮抗较大剂量镉对胎鼠的致畸作用。

Objective To observe whether the low dose cadmium pretreatment on fetal rats can antagonize the teratogenic effect induced by high dose cadmium,and provide the basis for the control of cadmium concentration in the environment.Methods A total of 60 pregnant Sprague-Dawley rats were randomly divided into control group,experiment group 1（ 0.06 mg·kg^-1 Cd^2＋ dose group）,experiment group 2（ 0. 06 mg·kg^-1 Cd^2＋ 5. 00 mg·kg^-1 Cd^2＋ dose group） and experiment group 3（ 5. 00 mg·kg^-1 Cd^2＋ dose group）,15 rats in each group. Intraperitoneal injection and daily weighing were adopted in these groups. Pregnant rats after 19 d were sacrificed by cervical dislocation. The uterine and ovarian morphology were checked by abdominal examination. The number of live births,resorption and fetal deaths were recorded,live fetus weight,tail length and tail length of skull were measured,the outlines of live fetus were observed. Results Ovarian effusion and hemorrhage occurred in experiment group 2 and 3. The stillbirth rate,absorbed fetus rate of experiment group 2 and 3 were significantly higher than those of control group and experiment group 1（ P〈0. 05） in which the average body weight in fossa were significantly lower than control group and experiment group 1（ P〈0. 05）. The stillbirth rate and absorbed fetus rate in experiment group 2 were significant lower than those in experiment group 3（ P〈0. 05）,while the average body weight in fossa was significantly higher than that in experiment group 3（ P〈0. 05）. The rib deformity rate among the groups had significant difference（ P〈0. 05）. Conclusion Intraperitoneal injection of 0. 06 mg·kg^-1 Cd^2＋ can antagonize the teratogenic effect induced by large dose of cadmium to a certain degree.