Expression levels of mRNAs encoding key appetite-regulating peptides in the brain (A–D) and hypothalamus (E–L) of male (left) and female (right) zebrafish (ZF) 1 h after intraperitoneal administration of 100 and 1,000 ng/g body wt of phoenixin-20 (PNX-20). NPY, neuropeptide Y; POMCa, proopiomelanocortin a; CART, cocaine- and amphetamine-regulated transcript; GHSRa, growth hormone secretagogue receptor-a; GOAT, ghrelin O-acyltransferase. Data obtained by real-time quantitative PCR are presented as means ± SE (n = 6 fish/group). ★P < 0.05, significant differences between control and treated groups. One-way ANOVA followed by Tukey’s multiple-comparison test was used for statistical analysis.