Skip to main content
. 2019 Dec 18;13:557. doi: 10.3389/fncel.2019.00557

Figure 3.

Figure 3

Dopamine activates Kv7/M in VTA DA neurons through dopamine D2 receptor and related cell signaling. (Ai,ii). Example of time-course of Kv7/M currents activated by DA in the presence of D2 receptor inhibitor sulpiride (300 nM) and D1 receptor inhibitor SCH23390 (1 μM). (Aiii) Summarized effects of D2 receptor agonist quinpirole (300 nM), sulpiride (300 nM), SCH23390 (1 μM) and Kv7/M channel inhibitor XE991 (3 μM) on DA-induced activation of Kv7/M currents in VTA DA neurons. ***p < 0.001, **p < 0.01, *p < 0.05; N.S., not significant, paired t-test. N = number of animals; n = number of recordings. (B) Effect of sulpiride (300 nM) and SCH23390 (1 μM; i,ii) on the resting membrane potential of VTA DA neurons. Summarized effects of sulpiride and SCH23390 on DA-induced hyperpolarization of VTA DA neurons (iii). *p < 0.05; N.S., not significant, One-way repeated-measures ANOVA with Bonferroni test. (C) Example traces from cell-attached recordings of VTA DA neurons activated by DA in the presence of sulpiride and SCH23390 are shown in (Ci). (Cii) Summarized effects of DA, sulpiride and SCH23390 on DA-induced inhibition of the spontaneous firing in VTA DA neurons. *p < 0.05; N.S., not significant, paired t-test. (D) Pre-treating VTA DA neurons with Pertussis toxin (PTX) for 6–9 h abolished the DA-induced activation of Kv7/M channels. N.S, not significant; paired t-test. (E) Reducing agent dithiothreitol (DTT) blocked the DA-induced activation of Kv7/M channels in VTA DA neurons. ***p < 0.01; N.S. not significant; one-way repeated-measures ANOVA with Bonferroni test. (F) Pretreating VTA DA neurons with ACSF for 6–9 h did not affect the DA-induced activation of Kv7/M channels. *p < 0.05; paired t-test. (G) Repeated application of DA induced a similar degree of Kv7/M activation. **p < 0.01, paired t-test. N = number of animals; n = number of recordings.