Fig. 4

Mitochondrial content, muscle fiber vascularization, and intracellular lipid aggregates were increased with running and unaffected by satellite cell depletion. a Voltage dependent anion channel (VDAC) was evaluated via immunoblotting as a rough estimate of mitochondrial content. The density of the resulting immunopositive bands was quantified and normalized to actin as a loading control (arbitrary units). b Quantification of Oil Red O staining performed on plantaris muscle cross sections to depict muscle lipid droplets. c–f CD31 was used as an endothelial marker to estimate muscle fiber vascularization. Representative images from each experimental group. Scale bar = 100 μm. g Quantification of CD31⁺ events was performed using an automated thresholding program and is reported as CD31⁺ events per muscle fiber. Number sign denotes main effect of running. Data are presented as means ± SE, with significance set at p ≤ 0.05