Fig. 3.

Selective activation of POMC neurons in the Arc suppresses food intake in fasted viral POMC-ChR2 mice. (A) Blue light stimulation of POMC neurons induced a reduction of food intake in 4-h fasted viral POMC-ChR2 mice, F(2, 40) = 18.99, P < 0.0001; ****P < 0.0001; n = 21 mice. (B) Light stimulation of POMC neurons led to an increased latency for the mice to lick their paws during the hot-plate test, F(2, 30) = 8.82, P < 0.01; **P < 0.01; n = 16 mice. (C) Increased latency induced by light stimulation was blunted by pretreatment with opioid antagonist naloxone (10 mg/kg) in the hot-plate test, F(2, 28) = 6.797, P < 0.01; *P < 0.05; **P < 0.01; n = 15 mice. Repeated-measures one-way ANOVA followed by Turkey’s test were used for all above statistics. Box plots show median, mean (+), lower and upper quartiles (boxes), and minima and maxima (whiskers).