Fig. 2.

Glucose ingestion and Agrp neurons control substrate utilization independently. a Control and Agrp^Trpv1 mice received a bolus of saline or glucose (2 g kg⁻¹) via gavage followed by peripheral injection of capsaicin (10 mg kg⁻¹, intraperitoneal (i.p.)). b Respiratory exchange ratio (RER). c Mean RER after gavage (interaction: F_1, 40 = 9.82, P = 0.003; gavage solution: F_1, 40 = 8.20, P = 0.006; genotype: F_1, 40 = 71.31, P < 0.0001). d Fat utilization. e Mean fat utilization after gavage (interaction: F_1, 40 = 7.91, P = 0.007; gavage solution: F_1, 40 = 6.07, P = 0.01; genotype: F_1, 40 = 79.82, P < 0.0001). f Carbohydrate utilization. g Mean carbohydrate utilization after gavage (interaction: F_1, 40 = 8.29, P = 0.006; gavage solution: F_1 40 = 5.26, P = 0.02; genotype: F_1, 40 = 37.44, P < 0.0001). In c, e and g statistical analysis was performed using two-way analysis of variance (ANOVA) on the mean response after gavage and capsaicin injection; genotype (control vs. Agrp^Trpv1) and gavage infusion (saline vs. glucose) were used as factors for the ANOVA. Holm–Sidak’s multiple comparisons test (MCT) was used to find post hoc differences among groups. MCTs are indicated as *P < 0.05, **P < 0.01, ***P < 0.001 and ****P < 0.0001 in figure panels. Control mice + saline gavage (n = 11); control mice + glucose gavage (n = 12); Agrp^Trpv1 mice + saline gavage (n = 10); Agrp^Trpv1 mice + glucose gavage (n = 11). Dashed gray line indicates time of oral gavage and capsaicin injection