三聚氰胺对纤毛类原生动物梨形四膜虫的细胞毒性

三聚氰胺曾被用为牛类的非蛋白类氮源,并被非法掺入食品中从而提高其表观蛋白含量.实验利用一种单细胞真核生物模型--纤毛类原生动物梨形四膜虫(Tetrahymena pyriformis)研究了三聚氰胺的细胞毒性.结果显示,三聚氰胺对梨形四膜虫的生长速率具有抑制作用,并且这种抑制作用与三聚氰胺浓度成正相关性,其IC50值为0.78g·L-1.细胞同时发生形变.实验证明梨形四膜虫生物测定法相对于动物实验具有耗时短、成本低、操作简便的优势,在潜在毒性物质的风险性评估实验中可成为一种优良的替代模型.

Cytotoxicity Assessment of Melamine Using the Ciliated Protozoan Tetrahymena pyriforrnis

Melamine was once used as a non-protein nitrogen(NPN)source for cattle,and unethically added to food productions in order to increase the apparent protein content.In this study,the cytotoxicological impact of melamine was determined using a unicellular eukaryote bioassay model,the ciliated protozoan Tetrahymena pyriformis(T.pyriformis).The results showed a concentration-dependent inhibitory effect of melamine on the cell proliferation rate of T.pyriformis populations,and the IC50 value was estimated to be 0.78g·L-1.Deformed cells were also observed.Our experiment demonstrated that T. pyriformis bioassay,with advantages such as less time-consuming,lower cost and simpler operations,provides a good alternative in vitro method to animal experiments for the risk assessment of potentially toxic substances.