Figure 7.

Recovery of the skeletal muscle mass in mice after replacement of a tryptophan (Trp)-deficient diet with a standard diet. (a) Body weight changes measured twice per week. Female C57BL/6 mice (nine-week-old) were fed a Trp-deficient diet for 21 days, followed by 21 days of a normal diet (n = 5). (b) Serum Trp levels on days 21 and 42. (c) Weights of the tibialis anterior and gastrocnemius on days 21 and 42. (d) Diameters of muscle fibers in the hematoxylin- and eosin-stained tibialis anterior. (e) Serum myostatin levels on days 21 and 42. (f) Correlation between serum tryptophan and myostatin levels in C57BL/6 mice (n = 15). The Pearson product-moment correlation coefficient (r = 0.64) and p < 0.01. * p < 0.05.