Fluoxetine and Stress Inversely Modify Lateral Septal Nucleus-mPFC Neuronal Responsivity.

Fluoxetine and Stress Inversely Modify Lateral Septal Nucleus-mPFC Neuronal Responsivity. Behav Brain Res. 2018 Jun 07;: Authors: Contreras CM, Gutiérrez-García AG, Sánchez-Salcedo JA Abstract Several clinically effective antidepressants increase the neuronal firing rate in the lateral septal nucleus (LSN), a forebrain structure that is anatomically related to medial prefrontal cortex (mPFC) regions. mPFC function is related to depression and the regulation of fear. However, unknown is whether antidepressant treatment or chronic stress modifies the responsivity of neuronal LSN-mPFC connections. We performed single-unit extracellular recordings in the anterior cingulate cortex (ACC) and prelimbic (PL) and infralimbic (IL) regions of the mPFC during stimulation of the LSN in anesthetized male Wistar rats that received fluoxetine (1 mg/kg, 21 days) or were subjected to chronic mild stress (5 weeks). The results were compared with a control group (saline treatment, devoid of behavioral manipulations). Stimulation of the LSN produced an initial excitatory paucisynaptic response, followed by an afterdischarge, characterized by an increase in the neuronal firing rate. Opposite changes were induced by fluoxetine treatment and chronic stress exposure. Peristimulus histograms and unit-activity ratio analyses indicated that LSN-mPFC responsivity differed between fluoxetine treatment and chronic stress exposure. Fluoxetine reduced neuronal ...
Source: Behavioural Brain Research - Category: Neurology Authors: Tags: Behav Brain Res Source Type: research