title: Regulation of dorsal raphe nucleus function by serotonin autoreceptors: a behavioral perspective.
abstract: Neurotransmission by serotonin (5-HT) is tightly regulated by several autoreceptors that fine-tune serotonergic neurotransmission through negative feedback inhibition at the cell bodies (predominantly 5-HT(1A)) or at the axon terminals (predominantly 5-HT(1B)); however, more subtle roles for 5-HT(1D) and 5-HT(2B) autoreceptors have also been detected. This review provides an overview of 5-HT autoreceptors, focusing on their contribution in animal behavioral models of stress and emotion. Experiments targeting 5-HT autoreceptors in awake, behaving animals have generally shown that increasing autoreceptor feedback is anxiolytic and rewarding, while enhanced 5-HT function is aversive and anxiogenic; however, the role of serotonergic activity in behavioral models of helplessness is more complex. The prevailing model suggests that 5-HT autoreceptors become desensitized in response to stress exposure and antidepressant administration, two seemingly opposite manipulations. Thus there are still unresolved questions regarding the role of these receptors-and serotonin in general-in normal and pathological states.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Washington, Seattle, WA 98104, USA.
authors.forename: Ross A
authors.initials: RA
authors.lastname: McDevitt
authors.forename: John F
authors.initials: JF
authors.lastname: Neumaier
mesh_terms: D000818:Animals; D017660:Autoreceptors / Q000378:metabolism*; D004644:Emotions; D006801:Humans; D051379:Mice; D018345:Mice, Knockout; D023421:Models, Animal; D009474:Neurons / Q000166:cytology / Q000378:metabolism*; D017729:Presynaptic Terminals / Q000378:metabolism; D011903:Raphe Nuclei / Q000378:metabolism*; D051381:Rats; D044403:Receptor, Serotonin, 5-HT2B / Q000235:genetics / Q000378:metabolism*; D044263:Receptors, Serotonin, 5-HT1 / Q000235:genetics / Q000378:metabolism*; D012701:Serotonin / Q000378:metabolism*; D013312:Stress, Physiological; D009435:Synaptic Transmission / Q000502:physiology
chemical_list: D017660:Autoreceptors; D044403:Receptor, Serotonin, 5-HT2B; D044263:Receptors, Serotonin, 5-HT1; D012701:Serotonin