The effect of in utero undernutrition on skeletal muscle mitochondrial content from 14 wk old mice fed ad libitum (L) and after a 4 wk 40% calorie restriction (R). A) Crude mitochondrial yield of pooled skeletal muscle, n=6. B) Protein expression of mitochondrial complex IV (CIV) in quadriceps muscle homogenate, representative Western blot on bottom and quantification above, n=8. C,D) Tibialis anterior muscle sections were stained for cytochrome c oxidase (COX) activity, representative images (C) and quantification (D). Fiber intensity was calculated for an average of 213 ± 14 fibers per mouse, n=5. E–I) Protein expression of mitochondrial complexes I, II, III, and V relative to complex IV in isolated mitochondria, representative Western blot (I) and quantification (E–H), n=6. Values are mean ± SEM. Two-way ANOVA with Bonferroni post-hoc test, *=p<0.05, ** = p<0.01, *** = p<0.001, # = p<0.05 (C vs. U), ## = p<0.01 (C vs. U). Black = C (control offspring), white = U (in utero undernourished offspring).