title: Serotonin 5-HT4receptors modulate the development of glutamatergic input to the dorsal raphe nucleus.
abstract: The dorsal raphe nucleus (DRN) is a major serotonin (5-hydroxytryptamine, 5-HT)-producing region in the central nervous system. It receives glutamatergic inputs from several brain regions, which are reciprocally modulated by serotonergic signals. We investigated whether serotonin 5-HT4receptors (5-HT4Rs) play a role in the development of glutamatergic control of the DRN, with an emphasis on cortical inputs. Double-label immunohistochemistry and confocal microscopy were used to quantify vesicular glutamate transporter 1 (vGluT1)-immunoreactive terminals in the DRN of mice with a null-mutation in the 5-HT4R gene. We found no significant change in the overall density of vGluT1-positive terminals in homozygous and heterozygous mice, but heterozygous mice had a significantly higher density of vGluT1-positive terminals contacting serotonergic neurons. These results suggest that altered 5-HT4R expression may affect the development of cortical glutamatergic control of the DRN.
authors.affiliation: Department of Psychological and Brain Sciences, University of California, Santa Barbara, CA 93106-9660, USA.
authors.forename: Angela
authors.initials: A
authors.lastname: Chen
authors.affiliation: Department of Psychological and Brain Sciences, University of California, Santa Barbara, CA 93106-9660, USA.
authors.forename: Katherine D
authors.initials: KD
authors.lastname: Hubbert
authors.affiliation: Department of Psychological and Brain Sciences, University of California, Santa Barbara, CA 93106-9660, USA.
authors.forename: Pasha F
authors.initials: PF
authors.lastname: Foroudi
authors.affiliation: Department of Psychological and Brain Sciences, University of California, Santa Barbara, CA 93106-9660, USA.
authors.forename: Vivian F
authors.initials: VF
authors.lastname: Lu
authors.affiliation: Department of Psychological and Brain Sciences, University of California, Santa Barbara, CA 93106-9660, USA. Electronic address: skirmantas.janusonis@psych.ucsb.edu.
authors.forename: Skirmantas
authors.initials: S
authors.lastname: Janušonis
mesh_terms: D000818:Animals; D018698:Glutamic Acid / Q000378:metabolism*; D006579:Heterozygote; D006720:Homozygote; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation; D017729:Presynaptic Terminals / Q000378:metabolism; D011903:Raphe Nuclei / Q000502:physiology*; D044422:Receptors, Serotonin, 5-HT4 / Q000235:genetics / Q000502:physiology*; D059326:Serotonergic Neurons / Q000378:metabolism; D050598:Vesicular Glutamate Transport Protein 1 / Q000378:metabolism
chemical_list: D050598:Vesicular Glutamate Transport Protein 1; D044422:Receptors, Serotonin, 5-HT4; D018698:Glutamic Acid
keywords: Brain development; Brainstem; Glutamatergic; Serotonin; Synaptogenesis