Calcium channel subtypes and intracellular calcium stores modulate electric field-stimulated and -oriented nerve growth

In culture, embryonic spinal neurites from Xenopus laevis show striking growth responses to steady dc electric fields, at a time when endogenous electric fields of similar size impinge on the developing nervous system. A high proportion of cultured neurites reorient, with both turning and branching directed cathodally. Neurite growth rates are increased and growth is differential (faster cathodally than anodally). Voltage-dependent calcium channels and calcium release from intracellular stores are shown to control these events. However, the pharmacological sensitivities of these phenomena differ, indicating different control mechanisms.