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：1993
卷号：39
期号：2
页码：141-150
DOI：10.3177/jnsv.39.141
出版社：Center for Academic Publications Japan
摘要：The effects of dietary protein restriction on protein synthe-sis were investigated in perfused rat hindlimb. The fractional rate of protein synthesis was measured with [ 3H ] phenylalanine in young adult (7-week-old) rats fed a low protein (5% casein) diet and a protein-free diet for 3 weeks. The low protein diet (LPD) allowed a moderate gain in body weight. The fractional rate of protein synthesis fell to 70% of the control value in LPD group and further fell to less than a half in the protein-free diet (PFD) group. Thus, the protein synthesis rate decreased as the dietary protein content was reduced. The fall of protein synthesis was mainly accompanied by the reduction of RNA activity (mg pro-tein/mg RNA/day) rather than RNA concentration (RNA/protein). The rate of protein breakdown was calculated by subtracting growth rate from protein synthesis rate. The breakdown rate was decreased in LPD group and increased slightly in PFD group. From the low rates of protein synthesis and breakdown, it appears that dietary protein restriction, at least allowing a gain in body weight, makes the turnover rate slow down. The overall changes in protein synthesis obtained in the perfused hindlimb are consistent with the reported results in vivo.
关键词：perfused rat hindlimb;protein synthesis;protein breakdown;skeletal muscle;low protein diet;protein-free diet;RNA activity;RNA concentration
