Figure 11.

DL-175 acts as an orthosteric agonist of GPR84. Similar experiments to those of Figure 9 using GPR84-Gα_i2 expressing membranes assessed how the potency or DL-175 might be modulated in the presence of increasing concentrations of 2-HTP (A) or PSB-16671 (B). Increasing concentrations of antagonist 837 altered the observed potency of DL-175 in a manner consistent with the two ligands binding competitively. Schild slope = 1.04 ± 0.05, pA2 compound 837 = 8.84 ± 0.06 (C). By contrast, the effect of antagonist 837 on the function of PSB-16671 was consistent with noncompetitive interactions (D). Data are means ± SEM. n ≥ 3.