Laminin directs and facilitates migration and fiber growth of transplanted serotonin and norepinephrine neurons in adult brain

Laminin is a strong adhesive glycoprotein present in basement membrane, where it provides attachment for many cell types. This chapter describes and provides direct evidence that laminin has effects on neurite outgrowth of developing neurons in vivo, and demonstrates that laminin can be applied to increase fiber outgrowth of transplanted neurons and to guide the growing fibers in a given target direction, using transplantation of fetal neurons. The hypothesis of neuronal migration guided by glia in the cerebellum may be mediated by laminin, which is produced by glia in the cerebellum during development. The results presented in this chapter are consistent with the hypothesis that laminin provides adhesion for neuronal attachment and promotes neurite outgrowth. Laminin placed in the brain evidently provides preferential adhesion for developing neurons and their extending fibers. Laminin may prove to be clinically significant, as it can provide a means to stimulate and direct the growth of neuronal systems into selected target areas.