Modulation of noradrenergic neuronal firing by selective serotonin reuptake blockers.
Using in vivo extracellular unitary recording, the effect of short term (2-day) and long-term (21-day) administration of the selective 5-HT reuptake inhibitor (SSRI) paroxetine (10 mg kg(-1) day(-1), s.c. using osmotic minipumps) was examined on the spontaneous firing activity of locus coeruleus noradrenergic neurons. Long-term but not short-term treatment significantly decreased firing activity. Thus, it appears that enhancing 5-HT neurotransmission by sustained SSRI administration leads to a reduction of the firing rate of noradrenergic neurons. The SSRI paroxetine therefore alters the activity of noradrenergic neurons with a delay that is consistent with its therapeutic action in depression and panic disorder.
Szabo
S T
ST
Neurobiological Psychiatry Unit, McGill University, Montreal, Canada.
de Montigny
C
C
Blier
P
P
D000818:Animals; D015283:Citalopram / Q000494:pharmacology; D005071:Evoked Potentials / Q000187:drug effects*; D008125:Locus Coeruleus / Q000187:drug effects / Q000502:physiology; D008297:Male; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D017374:Paroxetine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology*
D015283:Citalopram; D017374:Paroxetine; D017367:Selective Serotonin Reuptake Inhibitors