The teratogenicity of N-methyl-D-aspartate (NMDA) receptor antagonists

While it is generally accepted that y-aminobutyric acid type A (GABA(A))-receptor agonists decrease anxiety by facilitating the neuronal influx of chloride, the site of action within the brain is not clearly delineated. To gain further insight into the locus of anxiolytic action of GABA in the brain, we measured the distribution of GABA-stimulated chloride influx in seven regions of the brain from high- and low-anxiety rats. Our results show a significant increase in GABA-gated chloride influx in the hypothalamus of rats exhibiting low anxiety. The role of the hypothalamus in the regulation of anxiety is briefly discussed.