Abstract: | Maintenance of wakefulness is established to accomplish muscarinic (M-) cholinergic receptor activation in the ventrolateral preoptic area of the hypothalamus. The "muscarinic" wakefulness is characterized by enhancement of electroencephalogram (EEG) power spectra in the 0.75-12 Hz band and by increase in brain temperature. Activation of nicotinic (N-) cholinergic receptors of the area produces an increase in the duration of slow wave sleep, EEG power spectra reduction in the 0.75-7 Hz band, a decrease in brain temperature. And its hyperactivation leads to wakefulness, during its episodes the brain temperature decreases. During M- and N-cholinergic receptor blockade, the sleep-wakefulness and thermoregulation changes opposite to their activation were found. It is suggested that M- and N-cholinergic receptors of the ventrolateral preoptic area in pigeons participate in the sleep-wakefulness regulation and this effect is related to influence of this area on GABA-ergic system. |