Fig. 1. Nor/epinephrine release in the PVN is sensitive to feeding and hunger signals.
a Schematic of fluorescent NE/E reporter, GRABNE2h. b GRABNE2h was selectively expressed in Sim1 neurons, and an optical fiber was placed over the PVN to monitor in vivo NE/E dynamics. c Representative photomicrograph showing fiber tip (FT) placement over PVN neurons expressing GRABNE2h sensor. Scale: 200 μm. d Average GRABNE2h fluorescent response following access to inedible control object or food in fasted mice. e Temporal heatmap of response from individual mice and f quantification during initial (segment P1) and prolonged (segment P2) access to object and food (n = 7 mice, 2-way RM ANOVA with Tukey’s multiple comparison, *p = 0.023, **p = 0.0076). g–i PVN GRABNE2h response to intraperitoneal administration of saline (control), ghrelin (0.5 mg/kg) and 2DG (450 mg/kg), shown as average response (g), temporal heatmap from individual mice (h), and quantification of mean z-scores (i, ghrelin and 2DG: 20–60 min; n = 6 mice, two-tailed, paired t-test). *p = 0.010, **p = 0.0035. Data are presented as mean values +/− SEM.