THE CARBOHYDRATE N-ACETYLGLUCOSAMINE IS INVOLVED IN THE GUIDANCE OF NEURITES FROM CHICK CILIARY GANGLION NEURONS THROUGH THE EXTRACELLULAR-MATRIX OF RAT SKELETAL-MUSCLE FIBER

In the present work we study the functional role of muscle cell extrac ellular matrix components in axonal guidance during synaptic regenerat ion. We focused on components recognized by the N-acetylglucosamine-sp ecific lectin called wheat germ agglutinin (WGA) that has been shown t o bind to the muscle cell extracellular matrix. We have used a cryocul ture bioassay which is based on the ability of chick ciliary ganglion neurons to grow on rat skeletal muscle cryostat sections [Covault, J., et al., J. Neurosci., 105 (1987) 2479-2488.]. In control cultures, ne urites extended upon the muscle sections closely associated to the mus cle cell surface. Masking WGA lectin receptors on the muscle cell surf ace perturbed the behavior of neurites. On WGA-treated sections, most of the neurites extended indiscriminately on intercellular and intrace llular regions. These results indicate that N-acetylglucosamine-bearin g molecules on muscle cell surfaces may play functional roles in the g uidance of neurites through the extracellular matrix.