Fig. 2. (A) Percentage of BA-D5-immunopositive fibers (slow) and unstained fibers (fast) is shown for 2-, 4- and 6-week-old neurotrophin 4/5 (NT-4/5)-treated soleus and untreated contralateral soleus muscle. Values represent means ± S.E.M. *=P<0.05 vs untreated. (B–E) Representative images taken from histological sections of rat soleus muscle obtained at 4 weeks and 6 weeks of age: untreated contralateral soleus (B,D); NT-4/5-treated soleus (C,E). Each section was stained with monoclonal antibody BA-D5, which is specific to the slow or I/b myosin heavy chain (MyHC) isoform. Immunopositive fibers were visualized with peroxidase-conjugated goat anti-mouse secondary antibody. Scale bar, 50 µm.