Fig. 2

AIS integrity coincides with microglial inflammatory response. a–f Microglia, visualized by Iba-1 immunolabeling, display a surveying phenotype with long, highly branched processes in saline-treated mice (a). Microglia display a highly reactive morphology with retracted, thickened processes at 6 h post-LPS injection (b) and maintain this morphology at 24 h (c), 3 days (d), and 1 week (e) post-LPS injection. Microglia appear to return to a surveying morphology at 2 weeks (f) post-LPS. Scale bar = 10 μM. g–l mRNA expression of inflammatory mediators in isolated cortical microglia from saline- and LPS-treated mice. Consistent with microglial morphologies, inflammatory markers are significantly upregulated by 6 h post-LPS injection. Maintenance of this pro-inflammatory phenotype is supported by the persistence of significantly elevated NOX2 expression which does not return to baseline levels until 1 week post-injection. Similarly, markers associated with resolution of inflammation are reduced following LPS injection, and expression of these markers does not return to control levels until 1 week post-injection. mRNA expression was evaluated by quantitative RT-PCR; values were normalized using the 2^−ΔΔCT method and were reported as mean expression ± SEM. An asterisk indicates significant difference (p < 0.05) from saline, and a ¥ indicates a difference between time points post-LPS injection