Serotonin and brain development: Role in human developmental diseases

Serotonin is known to play a role in brain development prior to the time it assumes its role as a neurotransmitter In the mature brain. Serotonin regulates both the development of serotonergic neurons (termed autoregulation of development) and the development of target tissues. In both cases, the astroglial-derived protein, S-100 beta plays a role. Disruption of serotonergic development can leave permanent alterations in brain function and behavior. This may be the case in such human developmental illnesses as autism and Down Syndrome. (C) 2001 Elsevier Science Inc.