Protein young rats

Amino acids essential for young rats (98) and fishes (99) have been reviewed. Rats preferably eat a diet with sufficient amounts of essential amino acids rather than one that is deficient (100). Each essential amino acid, consumed in self-selection, has been reviewed (101). A protein diet with an excess of essential amino acids has been described as a poor protein diet from investigations that showed remarkable growth inhibition and occurrence of fatty fiver disease in rats (102). This is called amino acid imbalance (103). 

Effect of Dietary Protein On Skeletal Integrity in Young Rats... 

By the 1930s many workers had shown that nutritionally inadequate proteins, such as zein from maize, could be effective as a source of nitrogen if supplemented by additional amino acids (for zein, tryptophan). Even if it contained all the essential amino acids, the amount of protein in the diet influenced the results. Osbome and Mendel found that if the diet contained 18% by weight casein, which is low in cystine, young rats grew, but if the amount of protein was diminished, added cystine was required to offset the relative deficiency of this amino acid. Later, after methionine had been discovered, it was shown to replace the need for cystine. 

In all experiments to be described, brains of 11-15 day old albino rats (Sprague-Dawley) were used. Young rats of this age were chosen because rapid accumulation of gangliosides and sialo-proteins have been reported to occur around this period (17). 

Stern M, Gellermann B, Wieser H. Food proteins and maturation of small intestinal microvillus membranes (MVM). III. Food protein binding and MVM proteins in rats fromnewbom to young adult age. J Pediatr Gastroenterol Nutr 1990 11 389-394. 

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