Figure 3.
2-AG inhibits locomotion in C. elegans quadruple dopamine receptor mutants remodeled to detect acute dopamine release. Wild-type, mutant, and remodeled animals were incubated in 2-AG, and locomotion was assayed as body bends/20 s, as described in Materials and Methods. a, To detect acute 2-AG-stimulated DA release, the Gαo-coupled D2-like receptor DOP-3 was expressed in the cholinergic motor neurons of DA receptor quadruple-null (DA quad) animals under the assumption that any 2-AG-dependent DA release would activate DOP-3 on the motor neurons, inhibit acetylcholine release, and inhibit locomotion. b, DA or 2-AG-dependent locomotory inhibition was restored in DA quad animals designed to measure acute DA release. The unc-17β promoter drives expression in the cholinergic motor neurons. * Indicates significantly different from wild-type animals at 15 min; † indicates significantly different from the same animals at time 0 (p ≤ 0.05). Data are presented as the mean ± SE (n) and were analyzed by two-tailed Student's t test using GraphPad software.