The role of leptin on arousal [648.09/E64]

BECK P; URBANO FJ; KEZUNOVIC N; WILBOURN A; GARCIA-RILL E

New Orleans, LA, USA

Congreso; 2012 Society for Neuroscience Meeting.; 2012

Society for Neuroscience

Leptin, a hormone regulating appetite and energy expenditure, is increased in obese individuals, although these individuals often exhibit leptin resistance. Obesity is characterized by sleep/wake disturbances such as increased REM sleep, increased night-time arousals, and decreased percentage of total sleep. Several studies have shown that short sleep duration is highly correlated with decreased leptin levels in both animal and human models. Arousal and REM sleep are regulated by the cholinergic arm of the reticular activating system, the pedunculopontine nucleus (PPN). The goal of this project is to determine the role of leptin in the PPN, and thus the possible link between obesity and related sleep disorders. Experiments were conducted on 9-17 day old rat brainstem slices. Population recordings showed that leptin potentiated the NMDA response within the PPN, an effect blocked by 2-amino-5-phosphovaleric acid (APV), a NMDA receptor antagonist. Whole cell patch recordings of PPN neurons showed that leptin decreased action potential (AP) amplitude (n=28), AP frequency (n=10, p