Figure 4. Oxidative capacity and mitochondrial respiration rate of PGC-1β^{(i)skm−/−} muscles.

(a,b) Histological staining of tibialis anterior from 18 and 26-week-old control and PGC-1β^{(i)skm−/−} mice for NADH (a) and succinate (b) dehydrogenase activity (left panels), and quantification of unstained fibers (right panels; n=6). Scale bar, 100 μm. (c) Mitochondrial respiration rates determined on saponin-skinned quadriceps fibers of 26-week-old control and PGC-1β^{(i)skm−/−} mice in the absence (V₀) and presence of ADP (V_MAX). (n=9). Data are represented as mean±s.e.m. *P<0.05, Student's t-test.