<prompt> Melatonin isSerotonergicDopaminergicAdrenergicEstrogenic  <response>: A Serotonergic Melatonin is synthesized by pineal parenchymal cells and secreted by them into the blood and CSF. It is synthesized from serotonin by N-acetylation and O-methylation. Formation and metabolism of Melatonin: Tryptophan; 5-Hydroxytryptophan 5-Hydroxytryptamine Serotonin N-Acetyl -5-methoxytryptamine Melatonin N-Acetyl-Serotonin metabolism 6-Hydroxymelatonin in Liver other metabolites in brain 