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Dopaminergic neurons of the substantia nigra pars compacta are autonomous pacemakers. This activity is responsible for the sustained release of dopamine necessary for the proper functioning of target structures, such as the striatum. Somatodendritic L-type Ca²⁺ channels have long been viewed as important, if not necessary, for this activity. The studies reported here challenge this viewpoint. Using a combination of optical and electrophysiological approaches in brain slices, it was found that antagonism of L-type Ca²⁺ channel effectively stopped dendritic Ca²⁺ oscillations but left autonomous pacemaking unchanged. Moreover, damping intracellular Ca²⁺ oscillations with exogenous buffer had little effect on pacemaking rate. Although not necessary for pacemaking, L-type channels helped support pacemaking when challenged with cationic channel blockers. Simulations suggested that the insensitivity to …