Figure 9From: Chronic stress enhances microglia activation and exacerbates death of nigral dopaminergic neurons under conditions of inflammation Effect of stress and lipopolysaccharide in astroglia in the substantia nigra. (A) Coronal section showing glial fibrillary acidic protein (GFAP) immunoreactivity in a vehicle-injected nonstressed animal (arrow points to injection site). A limited alteration restricted to the needle tract is observed. (B) High-magnification image of the area within the box in (A). (C) GFAP immunoreactivity in a lipopolysaccharide (LPS)-injected nonstressed animal. There is an area lacking GFAP immunoreactivity around the injection track (dotted encircled area). (D) High-magnification image of the square box in (C); the arrow shows the injection site. (E) GFAP immunoreactivity in a LPS-injected stressed animal. The area lacking GFAP immunoreactivity is bigger (dotted encircled area). (F) High magnification of the square box in panel E showing hypertrophic astrocytes surrounding the injection site. Scale bars: (A), (C) and (E), 500 μm; (B), (D) and (F), 100 μm. Abbreviations: V, vehicle; S, stress; L, lipopolysaccharide; SL, lipopolysaccharide injected into stressed animals; SLR, lipopolysaccharide injected into stressed animals treated with RU486 (mifepristone (11β-[p-(dimethylamino)phenyl]-17β-hydroxy-17-(1-propynyl)estra-4,9-dien-3-one)). (G) Quantification of the areas lacking GFAP immunoreactivity on the substantia nigra at the end of the treatments. Results are mean ± SD of at least four independent experiments expressed in millimetres squared. P < 0.001 by analysis of variance followed by least significant difference post hoc test for multiple comparisons. a, compared with vehicle (V); b, compared with stress (S); c, compared with lipopolysaccharide (L). SL, stressed animals injected with lipopolysaccharide; SLR, lipopolysaccharide injected into stressed animals treated with RU486.Back to article page