Fig. 2. Co-localization of -aminobutyric acid (GABA) and PV in somatosensory cortex. (A-D) Adult WT and (E-H) cD2^-/- mice. Sections, 10 µm. GABA+ (A,E) and PV+ (B,F) neurons and processes are distributed in all layers of the cortex and GABA-immunolabeled neuropil is moderately reduced in cD2^-/- compared with WT. GABA and PV overlay images (C,G) show that most GABA+ cells in the cortex contain PV; however, GABA-immunolabeled, PV-negative cortical neurons are not substantially increased in cD2^-/-. (D,H) The GABA- and PV-immunolabeled neuropil are most substantially reduced in the superficial cortical lamina. (I,J) In 40 µm sections, GFP-immunoreactive neuron numbers are reduced in cD2^-/-::GAD67^eGFP mice compared with cD2^+/+::GAD67^eGFP (see Fig. S5 in the supplementary material). Therefore, GABAergic neurons are truly lost in cD2^-/- mice.