CACNA1D and Parkinson disease: Of particular importance, we detected a functional Cav3.1 T-type Ca2+ channel compensation in SN DA neurons from Cav1.3 L-type Ca2+ channel KO mice, providing a novel homeostatic link between those channels, with implications for the intended chronic pharmacological block of Cav1.3 channels as PD-therapy, where this flexible signalling network might also need to be considered.