Figure 2. Both Cav1 and Cav3 Ca²⁺ channels contributed to dendritic Ca²⁺ oscillations in SNc DA neurons.

(A) Projection image of a SNc DA neuron recorded from with a somatic patch electrode containing Fura-2 showing Ca²⁺ transient in distal dendrite. From left, control condition (black trace), with bath incubation of either 1 μM isradipine (green trace) or 1 μM TTA-P2 (blue trace). Note diminished dendritic Ca²⁺ transient with 1 μM isradipine. (B and C) Box plots summarizing the average and the peak [Ca²⁺], respectively, of the control, isradipine, and TTA-P2 treatment for both proximal and distal dendrites. Sample sizes for proximal dendrites were as follows: control group, n = 28 neurons from 23 mice; isradipine-treated group, n = 6 neurons from 4 mice; and TTA-P2–treated group, n = 9 neurons from 7 mice. In distal dendrites, sample sizes were as follows: control group, n = 31 neurons from 22 mice; isradipine-treated group, n = 7 neurons from 6 mice; and TTA-P2–treated group, n = 11 neurons from 7 mice. Data were analyzed using 1-tailed Mann-Whitney U test with Dunn’s correction for multiple comparisons. *P < 0.05.