The effect of amino-oxyacetic acid on brain catecholamines.

Abstract

Abstract— —Administration of amino‐oxyacetic acid (AOAA) to rats induced a pronounced decrease of midbrain norepinephrine (NE) and adrenal epinephrine (E) after 30 min, at which time the GABA level of midbrain had increased to 117 per cent of the initial value. The concentrations of NE in the pons‐medulla and of dopamine (DA) in the cerebral hemispheres were not changed.Further increases in brain GABA were accompanied by a rise of NE in midbrain and pons‐medulla beginning 1 hr after AOAA administration. A rise of cerebral DA level was observed only after 4 hr. Six hours after AOAA administration the levels of both NE and DA in brain were reduced.From the results of these and other studies, where administration of small amounts of GABA were shown to affect brain NE and serotonin levels, it is suggested that monoamines may be involved in the physiological action of GABA in the brain.