(A) Schematic for monitoring calcium dynamics in dopamine neurons, and representative image of GCaMP6f in neurons expressing dopamine active transporter (Slc6a3, DAT neurons). Scale bar, 500 μm. (B) Average ΔF/F of GCaMP6f signals in DAT neurons of food-restricted mice following intragastric infusion of water (n=6), EtOH (n=6), or fat (n=4). (C) Heat maps reporting ΔF/F of the 490-nm signal of individual mice in (B). (D) Mean ΔF/F of the 490-nm signal in 90-s bins from mice infused with EtOH, fat, or water in (B) (n=4–6/group, two-way repeated measures ANOVA, p<0.001). (E) Maximum ΔF/F of the 490-nm signal following gastric infusion of mice in (B) (n=4–6/group, one-way ANOVA, p=ns). (F) Mean ΔF/F of the 490-nm signal from 0 to 20 min following gastric infusion of mice in (B) (n=4–6/group, one-way ANOVA, p<0.01). (G) Schematic for monitoring dopamine signaling in the nucleus accumbens (NAc), and representative image of neurons expressing the dopamine (DA) sensor. Scale bar, 500 μm. (H) Average ΔF/F of DA sensor in food-restricted mice following intragastric infusion of water, EtOH, or fat (n=5/group). (I) Heat maps reporting ΔF/F of the 490-nm signal of the recordings in individual mice in (H). (J) Mean ΔF/F of the 490-nm signal in 3-min bins from mice infused with EtOH, fat, or water in (H) (n=5/group, two-way repeated measures ANOVA, p<0.01). (K) Maximum ΔF/F of the 490-nm signal following gastric infusion of mice in (H) (n=5/group, one-way ANOVA, p=ns). (L) Mean ΔF/F of the 490-nm signal from 0 to 40 min following gastric infusion of mice in (H) (n=5/group, one-way ANOVA, p=ns). (M) Schematic for monitoring dopamine signaling in the dorsal striatum, and representative image of neurons expressing the dopamine (DA) sensor. Scale bar, 500 μm. (N) Average ΔF/F of DA sensor in food-restricted mice following intragastric infusion of water, EtOH, or fat (n=5/group). (O) Heat maps reporting ΔF/F of the 490-nm signal of the recordings in individual mice in (N). (P) Mean ΔF/F of the 490-nm signal in 3-min bins from mice infused with EtOH, fat, or water in (N) (n=5/group, two-way repeated measures ANOVA, p<0.001). (Q) Maximum ΔF/F of the 490-nm signal following gastric infusion of mice in (N) (n=5/group, one-way ANOVA, p=ns). (R) Mean ΔF/F of the 490-nm signal from 0 to 40 min following gastric infusion of mice in (N) (n=5/group, one-way ANOVA, p<0.05). Data are expressed as mean ± SEM, ns p>0.05, t-tests and post-hoc comparisons: *p<0.05, **p<0.01, ***p<0.001; ANOVA interaction: ∞∞p<0.01, ∞∞∞p<0.001; ANOVA main effect of group: ☼☼p<0.01, ☼☼☼p<0.001.