Figure 8.
State-dependent contribution of Ih and INaP to respiratory rhythm. A, States of active wakefulness, quiet wakefulness, non-REM and REM sleep are determined using electroencephalogram recordings and frequency spectra in freely behaving adult rats. B, Diaphragm muscle recordings and cycle-by-cycle frequencies at each sleep–wake state with bilateral application at the preBötC of aCSF. C, Bilateral microperfusion of ZD7288 (100 μm) and riluzole (50 μm) into both preBötCs reduced significantly respiratory frequency in states of quiet wakefulness, non-REM sleep, and REM sleep, but not in active wakefulness. D, Mean data for n = 5 rats confirmed the state-dependent effect of drug microperfusion on respiratory frequency. E, Blockade of Ih and INaP did not affect diaphragm amplitude. F, Correlation of distances of perfusion sites from preBötCs and efficacy of drugs showing that close perfusion to the preBötC produced stronger effects. G, Blockade of Ih and INaP and subsequent breathing reduction also reduced time spent in non-REM sleep. Values are shown as means ±SEM. *Indicates mean values significantly different from aCSF conditions with p < 0.05.