Fig. 3: Effects of chemogenetic activation of VTADA neurons during punishment.
a TH::Cre+ rats received Cre-dependent excitatory hM3D DREADD bilaterally into the VTA. b hM3D expression across animals included in analyses (N = 10). c Example expression of hM3D within VTA. d Timeline of task sessions, with arrows indicating when subjects received i.p. injections of CNO and/or vehicle control (Veh). A-CNO vs. A-Veh groups received CNO vs. Veh (respectively) before the first 2 sessions of punishment. All groups received CNO vs. Veh (within-subjects, order counterbalanced) in subsequent punishment expression, choice, and locomotor tests. e Mean ± SEM lever suppression ratios by acquisition group across last day of training (T) and punishment acquisition sessions. Grey shaded area indicates injection sessions. CNO acutely (but incompletely) reduced responding. On subsequent non-injection days, A-CNO rats exhibited a persistent deficit in punishment avoidance. f Mean ± SEM lever-press latencies by acquisition group across last day of training (T) and punishment acquisition sessions. CNO administration did not significantly affect lever-press latencies acutely. However, A-CNO rats pressed the punished R1 lever significantly faster than A-Veh rats on subsequent non-injection days. g Mean ± SEM lever suppression ratios during punishment expression tests. CNO injections acutely (but incompletely) reduced responding across acquisition groups. A-CNO rats continued to press punished R1 more than A-Veh rats during control injections. h Mean ± SEM lever-press latencies during punishment expression tests. i Mean ± SEM suppression ratios during choice tests. j Mean ± SEM distance traveled during locomotor tests. CNO acutely increased distance traveled across groups. *p < 0.05.
