AbstractsBiology & Animal Science

In this work the electrophysiological properties of SN DA neurons from juvenile and adult WT and CaV1.3 KO mice were studied in in vitro brain slices with patch-clamp techniques (whole-cell, perforated-patch and on-cell). The data indicates that CaV1.3 L-type calcium channels, and the related calcium signalling, are important for the AHP of murine SN DA neurons, as well as for determining their maximal firing frequency, as buffering internal calcium seemed to abolish the normally present depolarisation block in those neurons. Furthermore, experiments analysing the D2-autoreceptor response of SN DA neurons from juvenile mice revealed that the general loss of the L-type calcium channel CaV1.3 was compensated via T-type calcium channel activity in CaV1.3 KO mice. The compensatory T-type calcium channel activity enhances calcium mediated NCS-1 (neuronal calcium sensor 1)/D2-autoreceptor interaction and thus prevents the D2-autoreceptor desensitization in SN DA neurons from juvenile CaV1.3 KO mice.