Figure 1. Somatodendritic dopamine release is strongly decreased in Syt-1 cKO^DA mice.

(A and B) Schematic of recording (A) in the substantia nigra pars compacta (SNc) and of Syt-1 cKO^DA mice (B) generated as described before.²⁹ Exon numbers refer to coding exons.

(C–E) Example traces (C) and quantification of amplitude (D) and charge (E, area under the curve) of D2-IPSCs evoked by a single stimulus. Syt-1 control 20 cells/6 mice, and Syt-1 cKO^DA 23 cells/6 mice.

(F–H) Example traces of D2-IPSCs evoked by two electrical stimuli with a 1 s interval (F), and quantification of the first peak amplitude (G) and ratio of the amplitude of the second to the first D2-IPSC (H, paired pulse ratio). Syt-1 control 17 cells/7 mice, and Syt-1 cKO^DA 10 cells/4 mice. Data are mean ± SEM; ***p < 0.005 as determined by Mann Whitney rank-sum tests (D, E, and G) or an unpaired Student’s t test (H). For basal electrical properties, see Figure S1; for D2-IPSC rise times, see Figure S2.