title: Stress-related serotonergic systems: implications for symptomatology of anxiety and affective disorders.
abstract: Previous studies have suggested that serotonergic neurons in the midbrain raphe complex have a functional topographic organization. Recent studies suggest that stimulation of a bed nucleus of the stria terminalis-dorsal raphe nucleus pathway by stress- and anxiety-related stimuli modulates a subpopulation of serotonergic neurons in the dorsal part of the dorsal raphe nucleus (DRD) and caudal part of the dorsal raphe nucleus (DRC) that participates in facilitation of anxiety-like responses. In contrast, recent studies suggest that activation of a spinoparabrachial pathway by peripheral thermal or immune stimuli excites subpopulations of serotonergic neurons in the ventrolateral part of the dorsal raphe nucleus/ventrolateral periaqueducal gray (DRVL/VLPAG) region and interfascicular part of the dorsal raphe nucleus (DRI). Studies support a role for serotonergic neurons in the DRVL/VLPAG in inhibition of panic-like responses, and serotonergic neurons in the DRI in antidepressant-like effects. Thus, data suggest that while some subpopulations of serotonergic neurons in the dorsal raphe nucleus play a role in facilitation of anxiety-like responses, others play a role in inhibition of anxiety- or panic-like responses, while others play a role in antidepressant-like effects. Understanding the anatomical and functional properties of these distinct serotonergic systems may lead to novel therapeutic strategies for the prevention and/or treatment of affective and anxiety disorders. In this review, we describe the anatomical and functional properties of subpopulations of serotonergic neurons in the dorsal raphe nucleus, with a focus on those implicated in symptoms of anxiety and affective disorders, the DRD/DRC, DRVL/VLPAG, and DRI.
authors.affiliation: School of Psychological Science, La Trobe University, Melbourne, Australia.
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Hale
authors.forename: Anantha
authors.initials: A
authors.lastname: Shekhar
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Lowry
mesh_terms: D000818:Animals; D001007:Anxiety / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D019070:Cell Lineage / Q000235:genetics; D006801:Humans; D019964:Mood Disorders / Q000150:complications / Q000378:metabolism / Q000473:pathology*; D059326:Serotonergic Neurons / Q000378:metabolism / Q000473:pathology; D012701:Serotonin / Q000378:metabolism*; D013315:Stress, Psychological / Q000150:complications / Q000378:metabolism / Q000473:pathology*
chemical_list: D012701:Serotonin