L-type calcium channels in the regulation of neurite outgrowth from rat dorsal root ganglion neurons in culture

Dorsal root ganglion neurons from neonatal rats were grown in culture for 12 h and the extent of neurite outgrowth determined by counting the fraction of neurons with neurites. In the presence of high K+, veratridine or bradykinin the extent of neurite outgrowth was reduced by about 60%. The inhibitory effect of depolarisation was reversible and was abolished by nifedipine. gamma-Aminobutyric acid (GABA), baclofen and 2-chloroadenosine had no effect on neurite outgrowth in control cultures but abolished the inhibitory effect of depolarisation.