Histopathological analysis of pale tremor ( plt ) skeletal muscle. Hematoxylin and eosin staining (A) and (B) and succinate dehydrogenase staining (C) and (D) of cryosections from quadriceps of control (wild-type (WT)/littermate (LM)) and plt animals. Scale bars = 50 μm. (E) Quantitation of myofiber size from quadriceps muscle of 4-week-old plt and WT animals. There were significant reductions in myofiber size: 2,649 μm2 ±70 for WT vs 1,185 μm2 ± 32 for plt (n = 400 per condition, P < 0.0001).