Morgan B L, Naismith D J
J Nutr. 1980 Apr;110(4):618-26. doi: 10.1093/jn/110.4.618.
The study describes three experiments of similar design relating dietary protein to growth over a period of 16 days in rats prematurely weaned at 19 days of age. In experiment 1, group 1 was fed ad libitum a 10% caseindiet. Group 2 was pair-fed an isoenergetic 40% casein diet. Groups 3 and 4 received 3 g of the 10% casein and 40% casein diets, respectively. The experiment demonstrated that protein may be used to sustain growth when energy intake is restricted. In experiment 2, all rats were given 3 g of diet per day. Group 1 was given the 10% casein diet, group 2 the 40% casein diet, group 3 a diet with 10% casein plus 30% of a mixture of dispensable amino acids and group 4 the 10% casein diet plus an energy supplement. Results showed that amino nitrogen seems to be a requisite for organ protein synthesis. In experiment 3, group 1 ate the 10% casein diet, group 2 the amino acid-supplemented diet and group 3 the latter minus glycine. Group 3 showed increased liver and kidney growth. The inclusion of glycine in group 2 caused a further increment in organ protein content.
该研究描述了三项设计相似的实验，研究了在19日龄时提前断奶的大鼠中，饮食蛋白质与16天内生长情况之间的关系。在实验1中，第1组随意进食10%酪蛋白饮食。第2组配对喂食等能量的40%酪蛋白饮食。第3组和第4组分别摄入3克10%酪蛋白饮食和40%酪蛋白饮食。该实验表明，当能量摄入受限的时候，蛋白质可用于维持生长。在实验2中，所有大鼠每天给予3克饮食。第1组给予10%酪蛋白饮食，第2组给予40%酪蛋白饮食，第3组给予含10%酪蛋白加30%必需氨基酸混合物的饮食，第4组给予10%酪蛋白饮食加能量补充剂。结果表明，氨基氮似乎是器官蛋白质合成的必要条件。在实验3中，第1组进食10%酪蛋白饮食，第2组进食补充氨基酸的饮食，第3组进食后者减去甘氨酸的饮食。第3组肝脏和肾脏生长增加。第2组中加入甘氨酸导致器官蛋白质含量进一步增加。
