Fig. 2

Cross- (A, B) and longitudinal sections (C–G) from the uvula muscle of healthy subjects (A) and an OSA patient immunostained for desmin (DES, green) and laminin (white, except E). Bar graphs show the percentage of desmin negative fibers (H) and disorganized fibers (I) in healthy subjects and patients (* p<0.05, ** p<0.01). Muscle fibers showing typical positive DES expression are marked 1, fibers lacking DES are marked 2, and fibers with weak DES staining are marked 3. In the OSA patient, muscle fibers with segmental lack of DES are marked 4 and fibers with disorganized DES are marked 5. Note the higher variability in fiber size, connective tissue content, and irregularity in the distribution of DES in fibers from the patient compared to the healthy subjects. Note also the lower capillarization in the sample from the patient. Scale bar panels A–C=50μm, panels D–G = 25μm