Figure 3. Effect of acute central injection of RFRP-3 on food intake and expression of genes encoding hypothalamic peptides NPY and POMC in ad-libitum fed female jerboas at spring and autumn.

(A,B) Cumulative food intake (g food intake/100 g body weight) was measured 1 h, 2 h, 3 h, 5 h, and 24 hours following icv injection of 5 μg RFRP-3 or vehicle (0.9% NaCl) in ad-libitum fed female jerboas captured in spring (A) or autumn (B). Statistical evaluation was performed using two-way repeated measures ANOVA followed by Student-Newman-Keuls test; data are expressed as mean ± SEM (n = 4 per group). ***p < 0.001, **p < 0.01 and *p < 0.05 for significant differences between RFRP-3 and vehicle injected groups; (C,D) Semi-quantitative analysis of the labeling intensity of Npy mRNA in the arcuate nucleus (C) and quantitative measure of the number of neurons expressing Pomc mRNA in the arcuate nucleus (D) 1h30 after 5 μg RFRP-3 (black bars) or vehicle (grey bars) icv injections in spring and autumn female jerboas. Statistical evaluation was performed using two-way ANOVA followed by a post hoc Holm-Sidak test; data are presented as mean ± SEM (n = 4 per group). **p < 0.01 and *p < 0.05 for significant differences between RFRP-3 and vehicle injected group. Representative images of Npy (C) and Pomc (D) mRNA labeling in the arcuate nucleus of female jerboas of spring sacrificed 1h30 after RFRP-3 or vehicle icv injections are shown. Scale bars represent 100 μm. AU: arbitrary units; 3v, third ventricle; Veh, vehicle; ME, median eminence.