转豇豆胰蛋白酶抑制剂大米的致畸作用研究

目的　用表达杀虫蛋白CpTI(豇豆胰蛋白酶抑制剂 )的大米喂养Wistar大鼠 ,研究其是否具有致畸作用。方法　将断乳的Wistar大鼠随机分为 4组 ,转基因大米组、非转基因大米组、阴性对照组和阳性对照组 ,敌枯双为阳性对照物。转基因大米组含 78 3%转基因大米 ,非转基因大米组含 74 7%与转基因大米同品系的非转基因大米 ,两个对照组的饲料为AIN93G ,三种饲料的宏量及微量营养素的含量相同。大鼠性成熟后 ,进行传统的致畸实验 ,观察母鼠及胎鼠的情况。结果　转基因大米组的孕鼠增重、胎鼠体重、身长和尾长显著高阳性对照组 ,畸形率 (包括外观畸形、骨骼畸形和内脏畸形 )显著低于阳性对照组 (P <0 0 1) ,转基因大米组、非转基因大米组及阴性对照组间的所有指标均无显著性差异 (P >0 0 5 )。结论　此种转CpTI基因的大米对大鼠无母体毒性、胚胎毒性和致畸作用。

Study on the teratogenicity effects of genetically modified rice which expressed cowpea trypsin inhibitor on rats

Objective Rats were fed by transgenic rice which expressed insecticidal protein CpTI (cowpea trypsin inhibitor) to study if the transgenic rice possessed potential teratogenicity effects.Methods Weanling Wistar rats were randomly divided into four groups: transgenic rice group, non transgenic rice group, negative control group and positive control group. The diet of transgenic rice group contained 78.3% transgenic rice. The diet of non transgenic rice group contained 74.7% non transgenic rice which was the parent line of the transgenic one. The diet formula of the two control groups was AIN93G. The marco- and micronutrient content were equal in three diets. When the sexual maturation period of rats arrived, conventional teratogenicity test was performed. Results The body weight gain of pregnant rats and body weight, body length and tail length of fetal rats in transgenic rice group were significant higher than those in positive control group(P<0.01).The malformation rate of fetus in transgenic rice group was significant lower than that in positive control group(P<0.01). Conclusion There were no significant differences of all indexes among transgenic rice group, non transgenic rice group and negative control group (P>0.05). Judging from these results, the transgenic rice modified with CpTI was considered to have no maternal toxicity, embryotoxicity and teratogenicity effects.