A project is proposed to study the biochemical and physiologic ontogeny of gamma hydroxybutyric acid (GHB) in rat brain pre- and postnatally. These studies will encompass the development of synthetic pathways of GHB from its precursors, succinic semialdehyde and gamma-amino butyric acid (GABA), the development of electroencephalographic (EEG) and behavioral responses of the developing animal to GHB and the effects of pre- and postnatal treatment of ethosuximide on the electrical and behavioral effects of GHB in the developing animal. Electrical studies will encompass cortical and depth recordings with computer analysis of the EEG. Other biochemical studies will include the subcellular localizatin of GHB in brain and determination of specific GHB binding sites in brain.