CALCIUM-CHANNEL SUBTYPES AND INTRACELLULAR CALCIUM STORES MODULATE ELECTRIC FIELD-STIMULATED AND FIELD-ORIENTED NERVE GROWTH

In culture, embryonic spinal neurites from Xenopus laevis show strikin g growth responses to steady de electric fields, at a time when endoge nous electric fields of similar size impinge on the developing nervous system. A high proportion of cultured neurites reorient, with both tu rning and branching directed cathodally. Neurite growth rates are incr eased and growth is differential (faster cathodally than anodally). Vo ltage-dependent calcium channels and calcium release from intracellula r stores are shown to control these events. However, the pharmacologic al sensitivities of these phenomena differ, indicating different contr ol mechanisms. (C) 1995 Academic Press, Inc.