Abstract
Male-weanling rats were fed on a basal protein and a high-quality protein made of the basal protein pius 4 amino acids of L-threonine, L-methionine, L-lysine and L-trygtvphan. Levels of urinary α-aminoketanes (AK) of δ-aminolevulinic acid (ALA) and aminaacetone (AA) were assayed.
Urinary AK levels of rats on the high-quality protein were about 4 times higher than those of rats on the basal protein. It was supposed that the above-mentioned high levels originated from either quality of fed protein or any amino acid supplemented to the basal protein. With single supplementation of each of essential amino acids and glycine to the basal protein, it was clearly indicated that urinary AK levels were greatly risen by threonine, but were fallen by methionine. The other amino acids had not such properties. Furthermore, it was proved that change of urinary AK levels depended on that of AA levels without any relation to ALA levels.
