GNAI1 and psychiatric disorder: Activation of Gi-coupled pathways on pvMΦs via 5-HT1B receptors is also a potential mechanism for the regulation of macrophage polarization and inflammatory responses by tonic 5-HT release within the DRN, which may be relevant to the increasing importance of neuroinflammatory pathways in the etiology of psychiatric disorders (Brisch et al., 2017; Howerton et al., 2014; Watkins et al., 2014).