Determination of endogenous GABA released from the cerebral cortex slices of the rat by high-performance liquid chromatography with a series-dual electrochemical detector.

A new, simple, rapid and sensitive method for the determination of ?-aminobutylic acid (GABA) has been developed by high-performance liquid chromatography with electrochemical detection (LCEC). A new and unique technique for LCEC by using the reductive-oxidative mode of a dual electrochemical detector provided a simple and sensitive assay method for GABA. The standard curve was linear over a concentration range of 1-1000 ng. The detection limit for GABA was less than 0.5 ng. This new method was adapted to the assay of the transmitter released endogenously from the cerebral cortical slices of the rat. Endogenous GABA release evoked by high K(+) was reduced when superfusion was performed in the presence of 100 ?M forskolin.