Fig. 6

TAAR1 increases membrane excitability in TG neurons. a through c Representative traces (right panel) and summary data (right panel) demonstrating that 0.1 µM tyramine had no effects on Na⁺ channel currents (n = 9 cells, a), high-voltage-activated Ca²⁺ channel currents after 2 µM ω-conotoxin-GVIA treatment (n = 8 cells, b), or low-voltage-activated T-type Ca²⁺ channel currents (n = 11 cells, c) in small TG neurons. d Representative traces (left panel) and summary data (right panel) indicating that 0.1 µM tyramine decreased the action potential (AP) firing rate (n = 16 cells). **p < 0.01 vs. control, paired t test. e and f Tyramine at 0.1 µM shortened the first-spike latency (E, n = 16 cells) and lowered the AP threshold (F, n = 16 cells). *p < 0.05 vs. control, paired t test. g Summary data demonstrating that EPPTB (3 µM) treatment prevented the tyramine-induced increase in the AP firing rate (n = 13 cells). h and i Representative traces (left panel) and summary data (right panel) demonstrating that treatment with either PKC_θ-siRNA (n = 10 cells, h) or Kv1.4-siRNA (n = 11 cells, i) abolished the tyramine-induced increase in the AP firing rate