title: Acute and repeated administration of fluoxetine, citalopram, and paroxetine significantly alters the activity of midbrain dopamine neurons in rats: an in vivo electrophysiological study.
abstract: We examined the effect of the administration of the selective serotonin reuptake inhibitors (SSRIs) fluoxetine, citalopram, and paroxetine on the activity of spontaneously active dopamine (DA) neurons in the substantia nigra pars compacta (SNC) and ventral tegmental area (VTA) in anesthetized adult male Sprague-Dawley rats. This was accomplished using the technique of in vivo extracellular recording. A single injection of 2.5 mg/kg (i.p.) of fluoxetine significantly increased the number of spontaneously active SNC and VTA DA neurons. In contrast, a single injection of either 1 mg/kg (i.p.) of paroxetine or 5 mg/kg of fluoxetine significantly increased the number of spontaneously active VTA DA neurons. The repeated administration (one injection per day for 21 days) of all of the SSRIs produced a significant increase in the number of spontaneously active VTA DA neurons. Overall, our results indicate that the systemic administration of SSRI alters the activity of midbrain DA neurons with differential effects on VTA compared with SNC DA neurons.
authors.affiliation: Department of Psychiatry and Neurology, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan.
authors.forename: Yoshimoto
authors.initials: Y
authors.lastname: Sekine
authors.forename: Katsuaki
authors.initials: K
authors.lastname: Suzuki
authors.forename: P Veeraraghavan
authors.initials: PV
authors.lastname: Ramachandran
authors.forename: Thomas P
authors.initials: TP
authors.lastname: Blackburn
authors.forename: Charles R
authors.initials: CR
authors.lastname: Ashby
mesh_terms: D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000704:Analysis of Variance; D000818:Animals; D015283:Citalopram / Q000008:administration & dosage*; D004298:Dopamine / Q000378:metabolism*; D004334:Drug Administration Schedule; D005473:Fluoxetine / Q000008:administration & dosage*; D008297:Male; D008636:Mesencephalon / Q000166:cytology*; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D017374:Paroxetine / Q000008:administration & dosage*; D051381:Rats; D017207:Rats, Sprague-Dawley; D017367:Selective Serotonin Reuptake Inhibitors / Q000008:administration & dosage*
chemical_list: D015283:Citalopram; D004298:Dopamine; D005473:Fluoxetine; D017374:Paroxetine; D017367:Selective Serotonin Reuptake Inhibitors