Zebrafish is an emerging vertebrate model used in many different studies, such as developmental biology, genetics, neurochemistry and toxicology. ATP is a ubiquitous molecule that exerts several actions on CNS. Besides the energetic role, this nucleotide can act on purinergic signaling as neurotransmitter or co-transmitter, released with different molecules, like dopamine, serotonine and acetylcholine. ATP acts on specific P2 receptors, subdivided in two classes: ionotropic P2X receptors and metabotropic P2Y receptors. Inactivation of ATP signal is perfomed by cell-surface enzymes, named ectonucleotidases. The NTPDase family (nucleoside triphosphate diphosphohydrolase) cleaves tri and diphosphonucleosides into monophosphonucleosides, and an ecto-5'-nucleotidase is able to cleave AMP until the neuromodulator adenosine. Adenosine can trigger on inhibitory A1 and A3 and on facilitatory A2A and A2B receptors. Our laboratory investigates ectonucleotidase activities and purinergic signaling in central nervous system of zebrafish. The relationship between purinergic and cholinergic neurotransmission is also our research fields.