Effect of noradrenergic denervation of medial prefrontal cortex and dentate gyrus on recovery after sleep deprivation in the rat

The noradrenergic-locus coeruleus (LC) system has a regulatory influence on forebrain neuronal networks. We have previously shown that the amygdala is strongly implicated in the mechanism of rebound seen after a 10 h sleep de privation (SID). In the present study, our objective was to determine wheth er the medial prefrontal cortex and dentate gyrus (DG) which receive an imp ortant innervation from the LC, play a role in the rebound mechanisms. We f ound that microinjection of the specific noradrenergic neurotoxin, N-(2-chl oroethyl)-N-ethyl-2-bromobenzylamine, into these regions had no effect on t he increase in paradoxical sleep duration seen after SID, suggesting that n oradrenergic (NA) innervation of the prefrontal cortex and DG are not invol ved in sleep rebound regulation. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.