Figure 6

Mef2c is required for normal glycogen utilization in response to exercise. (A, B, C, D) Glycogen content was qualitatively analyzed in the soleus muscle from exercised (Run) and unexercised (No Run) control (ctl) and Mef2c ^SkMKO (cko) mice by periodic acid Schiff’s (PAS) stain at 10× magnification. Arrowheads depict regions of glycogen accumulation in exercised mice (C, D). Red staining marks glycogen staining. (E) Glycogen concentration was quantified by measuring the amount of glucose resulting from the breakdown of glycogen in the gastrocnemius muscle from unexercised (No Run) and exercised (Run) control and Mef2c ^SkMKO mice. Mef2c ^SkMKO mice abnormally accumulated glycogen in muscle in response to exercise compared to unexercised Mef2c ^SkMKO mice and compared to exercised control mice, *p < 0.05. Data are presented as milligrams of glucose per gram of muscle tissue used in the assay. Values shown are mean + standard deviation, n = 9.