Figure 10.
Developmental changes in the morphology and size of γ-aminobutyric acid (GABA)ergic neurons. (A) At 23 gestational weeks, GABAergic neurons (demonstrated by glutamic acid decarboxylase (GAD65/67) immunocytochemistry) are small and round with scant cytoplasm (arrowhead). (B) At 3 postnatal months they are large with abundant cytoplasm and multiple processes. (C) At 16 postnatal months they have a mature morphology with a granular appearance and without cellular processes. There is punctate GAD65/67 immunostaining in the neuropil at this age. (D) GABAergic neuronal diameters in the frontal association cortex increase significantly with age (p < 0.001, analyzed with age as continuous variable).