Figure 7

P1 versus P12 intracerebral expressions of MCP-1 and levels of CD68+ cells. MCP-1 was detected at 4 and 24 h post-HI in pups exposed to LPS +/-HI. No MCP-1 was detected 48 h after HI at P1 in brains exposed or unexposed to LPS+/-HI either by ELISA (A) or IHC (B) at 48 h post-HI. In contrast, following HI or LPS+HI at P12, MCP-1 was up-regulated in brains at 4, 24 and 48 h post-HI as shown by ELISA (A). IHC experiments (B, C) showed that this increased intracerebral MCP-1 expression (C, arrowheads) at P12 was only detected in the neocortex (C). CD68+ cells (E, arrowheads) were detected at P12 - not at P1 - at 48 h post LPS+HI in the neocortex and white matter ipsilateral to ischemia, i.e. in the areas of neocortical damage as illustrated in the schema (D). Protein detection was performed by ELISA on 3 to 4 brains assayed in duplicate at each time point under each experimental condition. IHC was performed at 48 h post-HI, in 3 to 4 brains under each experimental condition. *p < 0.05, **p < 0.01, ***p < 0.001, one-way ANOVA with Newman-Keuls post test. Scale bars = 15 μm (C, E)