The mammalian cerebral cortex is critical for sensory and motor integrations and, for higher-order cognitive functions. The construction of mammalian cortical circuits involves the coordinated interplay between cellular processes such as proliferation, migration and differentiation of neural and glial cell subtypes followed by accurate connectivity evolving in complexity in primates. Alteration in cortical development may induce the emergence of various pathological traits and behaviours. Among the large array of factors that regulate the assembly of cortical circuits, serotonin (5-HT) plays important role as a developmental signal that impacts on a broad diversity of cellular processes. 5-HT plays distinct roles during specific sensitive periods and is produced from various sources depending on the perinatal stage. Its roles are mediated by more than fourteen 5-HT receptors that are all G-protein coupled receptors except the ionotropic 5-HT type 3A receptor (5-HT3A) mediating rapid neuronal activation. Importantly, 5-HT metabolism and signalling are influenced by numerous epigenetic and genetic factors, including nutrition and gut microbiota, perinatal stress, infection and inflammation. In this review, we will recapitulate some evidences showing that dysregulation of 5-HT homeostasis and 5-HT3A signalling impairs distinct steps of cortical circuit formation leading to the predisposition of the onset of various psychiatric diseases.
Part of the book: Serotonin