转豇豆胰蛋白酶抑制剂大米90天喂养实验研究

目的　观察转豇豆胰蛋白酶抑制剂 (简称CpTI)的大米是否具有潜在的毒副作用。方法　将断乳的Wistar大鼠随机分为 3组 :转基因大米组 (T)、非转基因大米组 (N)和阴性对照组 (C)。T组饲料中含 78 3%的转基因大米 ,N组饲料中含 74 7%的非转基因大米。喂养大鼠 90天 ,称量每日进食量、每周体重身长。检测中期及末期的血常规和生化指标。 90天末 ,处死动物 ,取股骨测骨密度 ,称量脏器重量 ,计算脏器系数 ,并对脏器进行病理观察。结果　大部分指标T组与其他两组差异无显著性 ,雄性T组 1月末的身长较其他两组长 ,末期的血糖及ALT较其他两组低 ,雌性T组中期的红细胞计数及血红蛋白较其他两组高 ,雌性T组末期单核细胞计数较其他两组高 (P <0 0 5 )。但这些数值都在文献报道的正常范围内。结论　用转CpTI大米喂养大鼠 90天未发现其有对健康产生毒副作用的结果。

Study on food safety of genetically modified rice which expressed cowpea trypsin inhibitor by 90 day feeding test 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 toxic or adverse effects. Methods Weanling Wistar rats were randomly divided into three groups: T, N and C group. The diet of T group contained 78.3% transgenic rice. The diet of N group contained 74.7%non transgenic rice which was the parent line of the transgenic one. The diet formula of C group was AIN93G. The macro and micronutrient content were equal in three diets. The rats were fed for 90 days. Food intakes were weight every day, body weight were weight and body length were measured every week. In the middle and at the end of feeding period, haematological value and clinical chemistry parameters were measured, at the end of the 90th day, post mortem organ coefficient were measured, organ tissues analysis was performed and bone density was measured. Results In most situation, there were no significant differences among the three groups( P >0.05) and no histopathological damage were detected. At the end of the 1st month, the male rats' body length of the T group was longer than the other two groups and at the end of the test period, the male rats' blood glucose and ALT were lower than the other two groups. In the middle of the test period, the female rats' red blood cell number and hemaoglobin were higher than the other two groups and at the end of the test period, the female rats' monocyte number was higher than the other two groups ( P <0.05). But all of the results were in the normal range which had been reported before.Conclusion From the results of the 90 days feeding test of transgenic rice on rats there did not reveal any signs of toxic and adverse effects.