Fig. 4

Microglia observed in hippocampus CA1 region from the saline and LPS injection groups. a, coronal section containing parts of the CA1 and CC regions from saline injected rats (n = 3), immunostained with anti-Iba-1 serum. b, high magnification of the framed area in the CA1 region from A, showing ramified microglia in this area that are probably in the resting state. c, representative image of CA1 region abutted by CA2 on a coronal section following LPS injections (n = 3) at the day 3, immunostained by anti-Iba-1 serum. d-f, high amplification images from the framed areas in c, showing that many Iba-1 labeled hyper-ramified cells with hypertrophic somata are clustered together (d and e, wide, open arrows), and some Iba-1 positive cells manifest hypertrophic pseudopodia either (F, small arrowheads). G, CA1 region near and above the SB from LPS injection group at the day 6 --- 3 days after cessation of the injections. h, high magnification of the framed area from the g, in which clustered Iba-1 positive cells with hypertrophic somata are still visualized, but clusters contain fewer somata (wide, open arrows). Scale bars in a, c and g are 150 μm, and in b, d, e, f and h are 25 μm. SB, subiculum