摘要: Neurons using serotonin (5-HT) as neurotransmitter and/or modulator have been identified in the central nervous system representatives from all vertebrate clades, including jawless, cartilaginous and ray-finned fishes. The aim of this review is to summarize our current knowledge about anatomical organization serotonergic Furthermore, selected key functions 5-HT will be described. main focus adult brain teleosts, particular zebrafish, which increasingly used a model organism. It answer not only genetic developmental biology questions, but also issues concerning physiology, behavior underlying neuronal networks. many evolutionary conserved features zebrafish combined with ever increasing number tools its practical advantages promise great possibilities increase understanding system. Further, comparative studies several species provide us interesting insights into evolution important