食物蛋白质对幼鼠脑核酸、蛋白质含量和超微结构的影响

Influence of Dietary Proteins on Contents of DNA,RNA and Protein, and Changes of Morphology in Brain

本文研究了不同来源食物蛋白质对出生５及２６日龄Ｗｉｓｔａｒ大鼠脑中ＤＮＡ、ＲＮＡ和蛋白质含量及脑超微结构的影响。结果表明：全蛋、鱼肉及补充蛋氨酸和牛磺酸后的大豆组３者间，脑ＤＮＡ、ＲＮＡ和蛋白质含量无显著性差异（Ｐ＞０．０５），全谷组则均显著低于其它各组（Ｐ＜０．０５）。相关分析表明，食物蛋白质氨基酸评分与脑ＤＮＡ含量呈正相关（Ｐ＜０．０５）。透射电镜下观察到全谷组大脑皮质及海马区有神经元固缩，核锯齿样变，线粒体肿胀、嵴断裂，粗面内质网扩张、核蛋白体颗粒脱落，神经毡区水肿等异常改变；而补充后的大豆组和全蛋组则结构正常。提示：在大鼠脑发育的快速增长期，脑细胞数及与蛋白质合成密切相关的膜性细胞器最易受到蛋白质营养不良的影响。

The contents of DNA. RNA, protein and morphological changes were derermined in the brains of the rats,aged 5 and 26 days, fed diets with either whole egg(EP), carp fish (FP ),soy + 0. 3 % methionine(Soyl ), soy + 0. 3 % methionine + taurine(Soy2 )or corn + gluten (CP ). The contents of DNA, RNA,protien of brain were lower in the groups of Soyl and CP than the diets with EP,Soy2 and FP. DNA contents were positively correlated with the amino acid score of the food proteins.When compared to rats fed either EP or Soy2, CP feeding caused several morphological changes in cerebral cortex and hippoccampus areas of rats brain: shrinkage of nucleus and cell body. swelling of mitochondria. dilatation of rough endoplasmic reticulum with detachment of ribosomes. The results suggest that the nutritional values of dietary protein affected the development of brain at early age.