Figure 1.

Increased food intake in NPF-specific insulin receptor knock-down flies. (A) Food intake in flies with InR RNAi knockdown in NPF+ neurons was significantly increased (n ≥ 9, 5 animals per replicates). (B) Unaltered activity in flies with InR RNAi knockdown in NPF+ neurons (n ≥ 29 animals). (C) Glycogen storage in flies with InR RNAi knockdown in NPF+ neurons was significantly increased (n ≥ 8, 10 animals per replicates), one-way ANOVA with Welch's correction. (D) Flies with InR RNAi knockdown in NPF+ neurons survived longer under starvation (n = 32 animals). (E) Assessment of Cre-recombination at the level of genomic DNA in central and peripheral tissues of IR^lox/lox and IR^lox/lox;NPY^Cre/+ mice. A 435 bp band confirms the rearrangement of the IR locus. (F) IR^lox/lox,tm and IR^lox/lox;NPY^Cre/+,tm mice were injected with 3 doses of tamoxifen (75 mg/kg body weight) and assessment of Cre-recombination at the level of genomic DNA in central and peripheral tissues. (G) IR^lox/lox and IR^lox/lox;NPY^Cre/+ mice or (H) IR^lox/lox,tm and IR^lox/lox;NPY^Cre/+,tm were i.c.v. injected with either saline or insulin (2.5 mU in 2 μl), and PFA perfused brains were extracted and processed for immuno-histochemistry with antibodies to p-Akt. Representative photomicrographs showing p-Akt (Green), mCherry (Red), and colocalization (Yellow) in the ARC of the hypothalamus. (I–K) IR^lox/lox and IR^lox/lox;NPY^Cre/+ mice were fasted overnight and i.c.v. injected with saline or insulin (10 mU in 2 μl, 2 h), RNA was isolated from hypothalami and expression of Pomc, Agrp, and Npy mRNA were determined using quantitative RT-PCR. Rpl19 was used as control. (E–K, n = 3–5 per group). Data are means ± SEM. *p < 0.05.