Cholinergic modulation of gamma band activity in the reticular activating system (RAS) [137.06/B46]

KEZUNOVIC N; HYDE J; SIMON C; GOITIA B; URBANO FJ; GARCIA-RILL E

New Orleans, LA, USA

Congreso; 2012 Society for Neuroscience Meeting.; 2012

Society for Neuroscience

The Reticular Activating System (RAS) modulates fast rhythms occurring during waking and paradoxical sleep. The pedunculopontine nucleus (PPN) modulates waking through ascending projections to the parafascicular nucleus (Pf) of the intralaminar thalamus, and paradoxical sleep through descending projections to the dorsal subcoeruleus nucleus (SubCD). The presence of gamma band activity has been reported in all cells in these nuclei. The present study was undertaken to determine how cholinergic input modulates gamma band activity in these centers. Whole cell patch clamp recordings were conducted on 9-15 days old rat brainstem slices. Neurons in 9-12 day rat Pf (n=42) and PPN (n=63) showed beta and gamma frequency oscillations at around -20 mV membrane potential during depolarizing ramps. Cells that were chronically exposed to the cholinergic agonist carbachol (CAR) showed significantly higher frequencies compared to those without CAR in both nuclei (51.7±2.5 Hz vs. 24.6±2.1Hz, p