Figure 5. Optogenetic stimulation of VMH^Ano4 neurons promotes food intake, induces hyperglycemia, and transmits a positive valance.

(A) Schematic representation of injection of AAV2-EF1a-DIO-hChR2 (H134R)-EFYP into the VMH and implantation of optical fiber in Ano4-P2A-Cre mice (male, 8–12 weeks of age). (B and C). Effects of optogenetic stimulation of VMH^Ano4 neurons on food intake in satiated (B) and fasted condition (C) (n = 12). (D–K) Effects of optogenetic stimulation of VMH^Ano4 neurons on blood glucose in a basal state (D and E), in GTT (F and G), in ITT (H and I) or during glucopenia induced by 2-DG (J and K) (n = 12). (L–N) Time spent and distance travelled and velocity in each respective chamber for Ano4-P2A-Cre mice with injection of AAV2-EF1a-DIO-hChR2 (H134R)-EFYP into the VMH during real-time place preference test (n = 12). (O–Q) Distance travelled, velocity, and time spent in the center for Ano4-P2A-Cre mice with injection of AAV2-EF1a-DIO-hChR2 (H134R)-EFYP into the VMH during open field test. BS refers to baseline (n = 12). Data are expressed as mean ± SEM. Significant differences between groups are shown as *P < 0.05 and **P < 0.01 determined by 2-way ANOVA followed by Bonferroni tests for D, H and J, 2-tailed paired Student’s t test for B, E, I and K, and 2-tailed unpaired Student’s t-test for L). Red arrows indicate where glucose (F), insulin (H) or 2-DG (J) was injected.