Multimodal antidepressant vortioxetine increases frontal cortical oscillations unlike escitalopram and duloxetine--a quantitative EEG study in rats.
OBJECTIVE
EEG studies show that 5-HT is involved in regulation of sleep-wake state and modulates cortical oscillations. Vortioxetine is a 5-HT3 , 5-HT7 , and 5-HT1D receptor antagonist, 5-HT1B partial agonist, 5-HT1A agonist, and 5-HT transporter inhibitor. Preclinical (animal) and clinical studies with vortioxetine show positive impact on cognitive metrics involving cortical function. Here we assess vortioxetine's effect on cortical neuronal oscillations in actively awake rats.


METHODS
Telemetric EEG recordings were obtained with the following treatments (mg·kg(-1) , s.c.): vehicle, vortioxetine (0.1, 1.0, 3.0, 10), 5-HT1A agonist flesinoxan (2.5), 5-HT3 antagonist ondansetron (0.30), 5-HT7 antagonist SB-269970-A (10), escitalopram (2.0), duloxetine (10) and vortioxetine plus flesinoxan. Target occupancies were determined by ex vivo autoradiography.


RESULTS
Vortioxetine dose-dependently increased wakefulness. Flesinoxan, duloxetine, ondansetron, but not escitalopram or SB-269970-A increased wakefulness. Quantitative spectral analyses showed vortioxetine alone and with flesinoxan increased θ (4-8 Hz), α (8-12 Hz) and γ (30-50 Hz) power. Duloxetine had no effect on θ and γ, but decreased α power, while escitalopram produced no changes. Ondansetron and SB-269970 (≈31-35% occupancy) increased θ power. Flesinoxan (≈41% occupancy) increased θ and γ power.


CONCLUSIONS
Vortioxetine increased wakefulness and increased frontal cortical activity, most likely because of its 5-HT7 and 5-HT3 antagonism and 5-HT1A agonism. Vortioxetine differs from escitalopram and duloxetine by increasing cortical θ, α and γ oscillations. These preclinical findings suggest a role of vortioxetine in modulating cortical circuits known to be recruited during cognitive behaviours and warrant further investigation as to their clinical impact.
Department of BioAnalysis & Physiology, Lundbeck Research USA, Inc., Paramus, NJ, USA.
S C
SC
Leiser
A L
AL
Pehrson
P J
PJ
Robichaud
C
C
Sanchez
D000818:Animals; D000928:Antidepressive Agents / Q000494:pharmacology*; D015283:Citalopram / Q000494:pharmacology; D000068736:Duloxetine Hydrochloride; D004569:Electroencephalography; D005625:Frontal Lobe / Q000187:drug effects* / Q000502:physiology; D008297:Male; D010879:Piperazines / Q000494:pharmacology*; D016601:RNA-Binding Proteins / Q000502:physiology; D017207:Rats, Sprague-Dawley; D011985:Receptors, Serotonin / Q000502:physiology; D013440:Sulfides / Q000494:pharmacology*; D013876:Thiophenes / Q000494:pharmacology; D000078784:Vortioxetine; D014851:Wakefulness / Q000187:drug effects
D000928:Antidepressive Agents; D010879:Piperazines; D016601:RNA-Binding Proteins; D011985:Receptors, Serotonin; C482440:Sert1 protein, rat; D013440:Sulfides; D013876:Thiophenes; D015283:Citalopram; D000078784:Vortioxetine; D000068736:Duloxetine Hydrochloride