Fig. 8: Refeeding activates PVH^TrkB neurons projecting to the VMH and the LPBN.

a–c Refeeding after overnight food deprivation induced Fos expression in PVH^TrkB neurons projecting to the VMH. PVH^TrkB→VMH neurons were labeled by tdTomato and CTB488 injected into the VMH in tamoxifen-treated Ntrk2^CreER/+;Rosa26^Ai9/+ mice (a). Arrowheads denote neurons positive for tdTomato and CTB488, while arrows indicate neurons positive for tdTomato, CTB488 and Fos (b). Fos induction in PVH^TrkB→VMH neurons under fasting and refeeding conditions was quantified (c). n = 3 mice in the fasted group and three mice in the refed group. Two-tailed unpaired t test; ***P = 0.0004. d–f Refeeding after overnight food deprivation induced Fos expression in PVH^TrkB neurons projecting to the LPBN. PVH^TrkB→LPBN neurons were labeled by tdTomato and CTB488 injected into the LPBN in tamoxifen-treated Ntrk2^CreER/+;Rosa26^Ai9/+ mice (d). Arrowheads denote neurons positive for tdTomato and CTB488, while arrows indicate neurons positive for tdTomato, CTB488 and Fos (e). Fos induction in PVH^TrkB→LPBN neurons under fasting and refeeding conditions was quantified (f). n = 3 mice in the fasted group and three mice in the refed group. Two-tailed unpaired t test; **P = 0.006. Error bars indicate SEM. Scale bars represent 50 μm. Source data are provided as a Source Data file.