l-2,4-Diaminobutyric acid and the GABA system

The effects of l-2,4-diaminobutyric acid (DABA) on GABA levels and on the activity of GABA metabolizing enzymes have been studied in a number of rat brain regions after both acute and chronic administration. Kinetic studies indicated that DABA was a non-linear, non-competitive inhibitor of GABA transaminase activity. The DABA-induced elevation of GABA levels paralleled the inhibition of GABA transaminase activity. DABA was a more effective inhibitor of GABA transaminase in vivo than in vitro, and this inhibition probably produced the elevation of GABA levels. The neurotoxicity of DABA appears to produce a use in GABA replacement therapy.