标题：Effects of Valine on 15N Incorporation into Serum and Tissue Protein and Non-protein Fractions Following 15N-L-Leucine Administration to Normal and Liver-Injured Rats
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：1989
卷号：35
期号：6
页码：559-567
DOI：10.3177/jnsv.35.559
出版社：Center for Academic Publications Japan
摘要：Effect of proportion of three branched-chain amino acids (leucine, valine, and isoleucine: BCAA) for nitrogen utilization was studied in vivo by an intragastric administration of 15N-L-leucine to control rats and liver-injured rats treated with carbon tetrachloride (CCl4-rats). Following the administration of isonitrogenous dose of three amino acid solutions [Standard (i 5N-L-leucine, L-valine, L-isoleucine, and L-alanine; 11, 8, 6, 18 mg/ml), Low-Val (11, 2, 6, 23 mg/ml), and High-Val (11, 32, 6, 0 mg/ml)], 15N enrichments in serum albumin, liver, skeletal muscle, and brain proteins and non-protein fractions, and urea nitrogen were compared by using 15N-analyzer. In CCl4-rats, the 15N enrichment in liver protein fraction was significantly lower in the High-Val group than in the Low-Val group. However, the difference of 15N enrichment in serum albumin between Low-Val and High-Val groups in CCl4-rats was unclear. The 15N enrichments in non-protein fractions of the brains in CCl4-rats were about twofold those in the skeletal muscles and the highest 15N enrichment was recognized in the Low-Val group. In the non-protein fraction of skeletal muscle in CCl4-rats, significantly low 15N enrichment was shown in the High-Val group compared with the Low-Val group. The 15N enrichment in urinary urea was significantly higher in the High-Val group than in the Low-Val group in CCl4-rats. In the Standard group of control rats, 15N enrichments in serum albumin and protein fraction of skeletal muscle were higher than in other groups. In non-protein fractions of control rats, the lowest 15N enrichment in liver and the highest 15N enrichment in skeletal muscle were recognized in the Standard group. These results suggest that a large amount of valine supplement among BCAA is less useful for leucine utilization in liver-injured rats than in normal rats.
关键词：branched-chain amino acid;15N-leucine;valine;15N enrichment;liver-injured rat
