Figure 2.
Effects of tau pff injections into hippocampus are dose and time dependent. A, Different amounts of K18/PL pffs (0.05, 0.5, and 5 μg) (top) or T40/PS pffs (0.05, 0.5, and 5 μg) (bottom) were injected into hippocampus, and mice were killed at 1, 2, and 4 weeks after injection. Each panel shows medial part of CA3 and dentate gyrus. Brain sections were stained with MC1 (left) and AT8 (right). Scale bar, 100 μm. B–E, Quantitative analyses of MC1-positive neurons in ipsilateral hippocampus (B), contralateral hippocampus (C), ipsilateral entorhinal cortex (D), and contralateral entorhinal cortex (E). Animals used for quantitative analyses were combined from both T40/PS and K18/PL injections. n = 5 for 1 week, n = 4 for 2 weeks, n = 8 for 1 month, n = 8 for 3 months, and n = 7 for 6 months. Significant differences between pairwise comparisons were marked with stars. *p < 0.05, **p < 0.01, ***p < 0.001. F, Quantitative analysis of NeuN-positive neurons at different time points after injection. There is no significant difference between any postinjection periods. The number of animals used for this analysis was the same as B–E. Ent Cortex, Entorhinal cortex.