Hypersynchronisation and sedation produced by GABA-transaminase inhibitors and picrotoxin: does GABA participate in sleep control?

Systemic administration of GABA-transaminase inhibitors, gamma-acetylenic GABA (100 mg/kg) or gamma-vanylic GABA (1200 mg/kg) produces behavioral picture of somnolence accompanied by EEG hypersynchronisation reminiscent of electrographic signs of petit mal epilepsy. Similarly, systemic administration of GABA antagonist, Picrotoxin (3--4 mg/kg) produces a short lasting period of sedation preceding the development of myoclonic jerks which is also accompanied by Wave-spike discharges. The role of GABA in sleep control is discussed. Although the area is not ready for firm conclusions, the results suggest that hyperactivity of GABA-ergic system as well as its hypoactivity could mediate pathological somnolence associated with different forms of epilepsy.