Figure 5.

GABAergic terminal plexuses surrounding pyramidal cells appear reduced in the tish cortex. GAD-65 immunoreactivity (green) was used to visualize GABAergic terminals, and NeuN immunoreactivity (red) was used to visualize neuronal nuclei. A, In control (Con) neocortex, GAD-65 immunoreactivity exhibits strong labeling surrounding layer V pyramidal cells. B–D, Higher magnification of the control cortex shows dense punctuate GAD-65 immunoreactivity surrounding layer V pyramidal neurons, which are labeled with NeuN. E, In the tish normotopic cortex, less intense GAD-65 immunoreactivity is observed in layer V compared with the control cortex (A). F–H, Higher magnification of the normotopic cortex reveals less dense and more dispersed GAD-65 labeling in the vicinity of layer V neurons compared with the control cortex (B, D). I, In the tish heterotopic cortex, GAD-65 labeling demonstrates an overall patchy pattern of immunoreactivity, consistent with the lack of laminar organization within the heterotopia. J–L, Higher magnification of the heterotopia demonstrates that some large pyramidal neurons are surrounded by punctate GAD-65 terminals. Arrowheads indicate smaller cell bodies that are GAD-65 immunoreactive, representing presumed interneurons. Scale bars: A, E, I, 100 μm; B–D, F–H, J–L, 25 μm. Con, Control; ttN, tish normotopic; ttH, tish heterotopic.