期刊名称:Journal of Nutritional Science and Vitaminology
印刷版ISSN:0301-4800
电子版ISSN:1881-7742
出版年度:1978
卷号:24
期号:5
页码:527-533
DOI:10.3177/jnsv.24.527
出版社:Center for Academic Publications Japan
摘要:Experiments were performed to investigate the mechanisms of the nutritional anemia caused by the excess methionine in rat, and the alleviative effects of glycine on it. After two months of feeding with 2.5% L-methionine on 9% casein diet, a moderate degree of anemia was manifested, but, the addition of glycine to the excess methionine diet prevented this phenomenon. The activity of heme-α-methenyl oxygenase, the key enzyme in the metabolic pathway of hemoglobin degradation, in the liver was not altered by the supplementation of either methionine or glycine to the diet. In order to investigate the mechanisms of the alleviation of the toxic effects of excess methionine by glycine, and also, whether glycine is the only amino acid which has the alleviative effect on the toxicities of excess methionine, two amino acids other than glycine, Lleucine and L-alanine had been chosen as the supplemental amino acid to the excess methionine diet. Deposition of iron in the spleen was greatly increased in the rat fed excess methionine diet, but not in the rat fed methionine + glycine diet. Activity of 5-aminolevulinic acid synthetase (ALAS), the key enzyme in .the hemoglobin biosynthesis, in the bone marrow was remarkably elevated by the addition of methionine, and only glycine could prevent this phenomenon. According to the results obtained, it is considered that the excess methionine would lower the biosynthesis of globin because of the amino acid imbalance. But the addition of glycine enhanced the metabolism of excess methionine, and this helps the accerelation of globin synthesis in the rat to promote the biosynthesis of hemoglobin.