The Effects of a Gabab Antagonist on Sleep in Adult Rats

GABAergic receptors are involved in different physiological and behavioural functions of the organism. Its inhibitory function and the broad distribution of GABA receptors in the central nervous system makes it worthwhile to investigate the role of GABA on sleep. Negative results were earlier found with the GABAA agonist muscimol (Mendelson and Martin, 1990), despite the fact that benzodiazepines facilitate the action of the GABA receptor. Recently it was established that a GABAB antagonist, CGP 35348, facilitates REM sleep dose dependently (Puigcerver et al, 1996). This effect was found in old rats with quite a number of spike-wave discharges. It cannot be excluded that the increase in REM sleep is more likely to occur in these particular old and epileptic rats than in younger adult rats. Furthermore, a short wash-out period was used. The aim of the present investigation is to replicate our earlier results with CGP 35348, but now in adult Wistar rats.