2-Arachidonoylglycerol and 1-arachidonoylglycerol activate heterologously expressed rat and human TRPV1.

<p>Current-voltage relationships after application of vehicle (Basal) or 2-arachidonoylglycerol (2-AG, 10 µM) to rat TRPV1-expressing CHO cells in the absence (A) and presence (B) of the protein kinase C inhibitor bisindoylmaleimide IV (BIM; 10 µM). Each current-voltage curve is representative of 3 cells. (C) Current traces showing responses to 10 µM 2-AG (left) and 10 µM 1-arachidonoyl glycerol (1-AG, right) in rat TRPV1-expressing CHO cells at a holding potential of −60 mV. Application of 10 µM of the TRPV1 antagonist capsazepine (Cz) immediately reversed the inward currents. (D) Excised inside-out patches from rat TRPV1-expressing CHO cells responded to 10 µM 2-AG with robust outward currents at a membrane potential of +60 mV. (E) Current-voltage relationships before and after application of 2-AG (10 µM) in HEK293 cells stably expressing human TRPV1. (F) Inward currents in HEK293 cells transiently expressing human TRPV1 at a holding potential of −50 mV. Traces show inward currents elicited by 2 µM capsaicin (CAP) and 10 µM 2-AG in a calcium free solution. Exposure to capsaicin and 2-AG a second time produced currents of similar magnitude. Data are presented as mean ± s.e.m. Kruskal-Wallis one-way ANOVA followed by Dunn's <i>post hoc</i> test was used for comparing groups of data. **<i>P</i><0.01, ***<i>P</i><0.001.