Glutamate and GABA in depression

Clinical and preclinical studies have shown that depression and chronic stress adversely impact both GABA and glutamate pathways, with clinical studies showing reductions in the volume of prefrontal cortex and hippocampus, reductions in the levels of synaptic markers, decreased somatostatin interneuron markers, and decreased levels of glutamic acid decarboxylase.⁷ Chronic stress has been shown to change the structure and reduce the function of glutamate neurons; the resulting atrophy of glutamate neurons is thought to contribute to the reduction in volume of cortical and limbic structures observed in depression.⁷

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