Inhibition by γ‐hydroxybutyrate of chlorpromazine‐induced increase in homovanillic acid

Abstract

1 γ-Hydroxybutyrate and its lactone precursor, γ-butyrolactone, when administered in anaesthetic doses block the increase in the cerebral concentration of homovanillic acid normally observed after administration of chlorpromazine or haloperidol. 2 Other hypnotics such as glutethimide, urethane, chloralose, chloral hydrate and thiopentone do not have this ability even when administered in anaesthetic doses. 3 The ability of γ-hydroxybutyrate to block the neuroleptic-induced increase in cerebral homovanillic acid is not due to a reduction in body temperature since a similar effect is observed in rats treated under conditions (32° C) in which body temperature remains normal. 4 Possible mechanisms for this action of γ-hydroxybutyrate are discussed.