von der Decken A, Lund B, O'Toole C
J Nutr. 1978 Aug;108(8):1274-80. doi: 10.1093/jn/108.8.1274.
Young adult rats (body weight 90 g) were given a low protein (3% casein) diet for 6 days. Under these conditions, thymus and spleen organ wet weights and DNA content decreased as compared with control rats given a high protein (20% casein) diet. The in vitro incorporation of amino acids into protein was followed using leucine as the radioactive precursor. Ribosomes of tissues from the dietary rats were incubated together with soluble enzymes from liver of rats fed a stock diet, and cofactors. Ribosomal capacity for leucine incorporation into protein diminished in thymus by 33% per mg ribosomal RNA, 77% per total ribosomal RNA, and 43% per mg DNA. In spleen the corresponding reductions were 29%, 81%, and 31%; in bone marrow the decrease was 29% per mg ribosomal RNA, 56% per total ribosomal RNA, and 19% per mg DNA. A reduction in physiological activity is thus evident in these tissues soon after protein restriction.
将年轻成年大鼠（体重90克）给予低蛋白（3%酪蛋白）饮食6天。在这些条件下，与给予高蛋白（20%酪蛋白）饮食的对照大鼠相比，胸腺和脾脏器官湿重及DNA含量降低。使用亮氨酸作为放射性前体追踪氨基酸在体外掺入蛋白质的情况。将饮食大鼠组织的核糖体与喂食常规饮食大鼠肝脏的可溶性酶及辅因子一起孵育。胸腺中核糖体将亮氨酸掺入蛋白质的能力，每毫克核糖体RNA降低33%，每总核糖体RNA降低77%，每毫克DNA降低43%。脾脏中的相应降低分别为29%、81%和31%；骨髓中每毫克核糖体RNA降低29%，每总核糖体RNA降低56%，每毫克DNA降低19%。因此，在蛋白质限制后不久，这些组织中的生理活性明显降低。
