Figure 4. ApoE4 Impairs GABAergic Interneurons and GABA Release in the Hippocampus.
(A–D) Immunostaining of GAD67-positive GABAergic interneurons in the hilus of female wildtype (A), apoE-KO (B), apoE3-KI (C), and apoE4-KI (D) mice at 6–7 months of age.
(E) Numbers of GAD67-positive GABAergic interneurons in different mice at 6–7 months of age. Values are mean ± SD (n = 4–7 mice per genotype). * p < 0.05 vs. wildtype and apoE3-KI mice (t test).
(F, G) Positive correlation between the number of GAD67-positive interneurons and the number of BrdU+/NeuN+ neurons among female wildtype, apoE3-KI, and apoE4-KI mice at 6–7 months of age (F, n = 12 mice) and at 3 months of age (G, n = 15 mice).
(H) GABA release in hippocampal slices, determined by mass spectrometry. Values are mean ± SD (n = 4–7 mice per genotype). * p < 0.05 vs. wildtype and apoE3-KI mice (t test).