Fig. 5: The antinociceptive effects of l-CDL were mediated by the D1–D2DR complex in CCI rats.

a–c The time course of the MWTs and TWLs of CCI rats after coadministration of the D1DR agonist SKF 38393 (2 μg/20 μL, i.t.), D2DR agonist quinpirole (2 μg/20 μL, i.t.), and D1–D2DR heteromer agonist SKF 83959 (2 μg/20 μL, i.t.) with l-CDL (15 mg/kg, p.o.). d–f The time course of the MWTs and TWLs of CCI rats after coadministration of the D1DR agonist SKF 38393 (2 μg/20 μL, i.t.), D2DR agonist quinpirole (2 μg/20 μL, i.t.), and D1–D2DR heteromer agonist SKF 83959 (2 μg/20 μL, i.t.) with l-CDL (15 μg/20 μL, i.t.) (n = 6; ###P < 0.001 vs the control group; *P < 0.05, **P < 0. 01, ***P < 0.001 vs the CCI group; $P < 0.05, $$P < 0. 01, $$$P < 0.001 vs the l-CDL group).