Stimulatory effect of intracerebroventricular administration of orexin A on food intake in the zebrafish, Danio rerio

► The number of orexin A-containing neuronal cells increases in zebrafish fasted for 7 days. ► Orexin precursor mRNA levels also increase in fish fasted for 7 days. ► ICV administration of orexin A increases food consumption in zebrafish. ► Orexin A-induced orexigenic action is blocked by treatment with SB334867.