Quinolinic acid lesions of the pedunculopontine nucleus impair sleep architecture, but not locomotion, exploration, emotionality or working memory in the rat

► We studied the effects of pedunculopontine nucleus quinolinic acid lesion in the rat. ► Duration and number of SWS and REM sleep stages correlated with lesion magnitude. ► Locomotion, exploration, emotionality, and working memory were unaffected. Anatomical and functional studies have shown that the NADPH-diaphorase-positive cholinergic neurons of the pedunculopontine nucleus (PPN) send projections to several areas in the brain. The purpose of this work was to investigate whether bilateral lesions with quinolinic acid, a neurotoxin with greater selectivity for NADPH-diaphorase-positive neurons, aimed at the compact portion of the PPN would affect the performance of adaptive behaviors, such as sleep, locomotion, and spontaneous alternation. Lesioned animals were divided in a low lesion group (LL,