[Development of connective tissue in mouse skeletal muscle]

The development of the connective tissue in the dorsal forelegs of mouse embryos and sucklings was investigated with the aid of immunofluorescence and electron microscopy. Collagen type III is visible earlier in the muscular connective tissue than collagen type I. However, it seems that collagen does not play a fundamental role in the organization of the muscular tissue. The occurrence of collagen is rather an indication of the mechanical development of the muscles. In early embryos (day 13 to day 15) some desmosome-like cell contacts are visible between fibroblasts and myoblasts, as well as myotubes.