title: [Effect of concurrent treatment of SSRI on the tyrosine hydroxylase immunoreactivity in the rat locus coeruleus treated with chronic variable stress].
abstract: Locus coeruleus (LC) is the major component of noradrenergic neurons in the brain. corticotropine-releasing hormone (CRH) and norepinephrine (NE) are suggested to play significant roles in the pathophysiology of depression, although the involvement of the serotonergic system in the CRH-NE systems is not elucidated. Chronic inescapable and unpredictable stress can result in a sustained dysregulation of both of CRH and NE systems. In the present study we have investigated the TH immunoreactivity in the LC by immunohistochemical staining in rats treated with chronic variable stress (CVS) and concurrent administration with clomipramine or fluvoxamine. There was a significant decrease in TH levels 24 h after the last stressor of CVS, followed by a further decrease in that of 72 h later, whereas a marked increase was observed in TH levels immediately after the last stress of CVS 13 d. Concurrent clomipramine and fluvoxamine treatment prevented the sensitization of TH reactivity and the delayed decrease until 72 h later. These data suggest that an increase in serotonin availability would contribute to the normalization of both hypoactivity and sensitization of LC-NE neurons modified under "chronically stressful" situations.
authors.affiliation: Department of Neuropsychiatry, St. Marianna University School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, 216-8511 Japan.
authors.forename: Sachiko
authors.initials: S
authors.lastname: Fujii
authors.forename: Mikio
authors.initials: M
authors.lastname: Asakura
authors.forename: Shigeto
authors.initials: S
authors.lastname: Kanai
authors.forename: Daisuke
authors.initials: D
authors.lastname: Tanaka
authors.forename: Takuji
authors.initials: T
authors.lastname: Hishinumai
authors.forename: Hideaki
authors.initials: H
authors.lastname: Nagashima
mesh_terms: D000818:Animals; D000929:Antidepressive Agents, Tricyclic / Q000494:pharmacology* / Q000627:therapeutic use; D002908:Chronic Disease; D002997:Clomipramine / Q000494:pharmacology* / Q000627:therapeutic use; D003346:Corticotropin-Releasing Hormone / Q000502:physiology; D004195:Disease Models, Animal; D016666:Fluvoxamine / Q000494:pharmacology* / Q000627:therapeutic use; D007150:Immunohistochemistry; D008125:Locus Coeruleus / Q000201:enzymology*; D008297:Male; D009638:Norepinephrine / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000502:physiology; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D013315:Stress, Psychological / Q000188:drug therapy / Q000201:enzymology*; D013997:Time Factors; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism*
chemical_list: D000929:Antidepressive Agents, Tricyclic; D002997:Clomipramine; D003346:Corticotropin-Releasing Hormone; D016666:Fluvoxamine; D009638:Norepinephrine; D012701:Serotonin; D017367:Selective Serotonin Reuptake Inhibitors; D014446:Tyrosine 3-Monooxygenase