FIGURE 7.

MuRF1^−/− mice are protected against high CO₂-induced muscle atrophy. MuRF1^−/− mice and wild-type littermates (MuRF1^+/+) were exposed to 10% CO₂ (HC) for 21 days or maintained in room air (CT), and soleus muscles were excised, frozen, and cryosectioned (8-μm thickness). A, measured grip strength from MuRF1^−/− mice and wild-type littermates. n ≥ 6. Results are represented normalizing the average grip of each mouse by the body weight (BW) at the corresponding day. B, soleus muscles from MuRF1^−/− mice and wild-type littermates were immunostained with laminin antibody and fiber CSA was analyzed. n ≥ 3). Scale bars, 50 μm. C, fiber size distribution histograms from MuRF1^−/− mice and wild-type littermates (n ≥ 6). *, p < 0.05.