RESUMEN
A collagen film in which the collagen fibers were aligned was prepared and characterized by scanning electron microscopy. Cell orientation on this film was studied in vitro using human fibroblasts and chick embryo myoblasts. Ninety-four percent of innoculated fibroblasts were aligned along the direction of the collagen fiber. The cell orientation was disturbed when cytochalasin B or colchicine was added to the culture medium. The myoblasts showed a similar alignment along the direction of collagen fiber. The scanning electron microscopic observation revealed that none of the cytoplasmic extensions had consistent relationships to the direction of collagen fiber. Myoblast fusion was accelerated on the aligned membrane as compared to a randomly oriented film, suggesting some role of contact guidance in muscle cell differentiation.