Representative photomicrographs of astrocytes (A to C, SN; D to F, striatum) in the rat brain after LPS injection. As shown by GFAP immunostaining in the SN (A) and striatum (D) in the control rat brain, some GFAP positive cells were detected and most of those cells were in resting status with fine processes extending from the main cellular processes (arrows indicated A and D). Significantly increased numbers of reactive astrocytes showing hypertrophy of cellular processes (arrows indicated in B and E) were observed in SN (B) and striatum (E) of the rat brain following neonatal LPS exposure. Celecoxib treatment reduced the number of reactive astrocytes stimulated by LPS in the above areas (C, F and G). The scale bar shown in A represents 50 μm for A to F. Quantitation of the number of GFAP + cells (G) and the percentage area of image that contained GFAP staining (H) in the SN and striatum were performed as described in Methods. The results are expressed as the mean ± SEM of six animals in each group, and analyzed by one-way ANOVA. *P <0.05 represents a significant difference for the LPS + Vehicle group as compared with the Saline + Vehicle group. #
P <0.05 represents a significant difference for the LPS + Celecoxib group as compared with the LPS + Vehicle group.