The actions of neurotransmitters involved in the sleep-wakefulness cyc
le on neurons located in the ventral part of the oral pontine tegmentu
m were studied in a rat brain-slice preparation. Results show that glu
tamate and histamine evoke depolarizations and spike firing while sero
tonin and gamma-aminobutyric acid evoke hyperpolarizations. The excita
tory and inhibitory actions of these neurotransmitters increase pontin
e neuron activity during the conditions occurring during paradoxical s
leep. (C) 1998 Elsevier Science B.V. All rights reserved.