Fig. 3.
Inhibition of HVA ICa by MrgprX1 agonist depends on the Gαi/o pathway. (A) Overnight pretreatment of DRG neurons from MrgprX1 mice with PTX (2 μg/mL, to block Gαi/o) abolished the inhibition of HVA Ca2+ currents (Ica) by BAM8–22 (BAM, 5 μM). (B) Overnight pretreatment with CTX (2 μg/mL, to uncouple Gαs functionally) did not affect BAM8–22-induced inhibition. (C) Acute perfusion with U73122 (5 μM, 3 min) to inhibit the phospholipase C pathway did not affect BAM8–22-induced inhibition. (D) Amplitude of BAM8–22-induced Ica inhibition in the absence (control) and presence of different blockers, normalized by the pre-BAM8–22 baseline. Controls are presented as a combined group. *P < 0.05 vs. respective control, Student t test (n = 5–6 neurons per group).