Fig. 5. Primary cultures of myoblasts express Cx43. (A) Primary cultures of satellite cell-derived myoblasts maintained for 48 hours in differentiation medium were fixed with ethanol and Cx43 was detected by immunofluorescence. Scale bar: 20 µm. (B) Western blot analysis of Cx43 in aliquots (100 µg of protein) of myoblast homogenates obtained at 0, 24 and 48 hours of differentiation. The non-phosphorylated (NP) and phosphorylated (P) forms of Cx43 are indicated.