Figure 5

Expression of c-Jun after LPS application. Coronal sections of motor cortex 3 days (Figs 5a, b), 2 weeks (Figs 5c – e) and 1 month (Fig. 5f) after unilateral application of LPS, or sham operation (Figs 5a, c), immunoreacted for c-Jun or CTB (insets to Figs 5b, d and f). Note that, at 3 days c-Jun is detectable in layers II, III and V at low levels immediately below the craniotomy on the control side, but is almost undetectable more medially and laterally, and that c-Jun immunoreactivity is much stronger on the treated side, predominantly in layers II, III and V, immediately below the site of LPS application. Note also the marked increase in c-Jun immunoreactivity in layers II, III and V immediately below the burr hole and site of LPS application in Fig. 5d compared to the corresponding contralateral cortex in Fig. 5c. The framed area of layer V in Fig. 5d is enlarged in Fig. 5e to show details of immunostained nuclei. The insets to Fig. 5b and d are taken from the section immediately serial to the ones shown in Figs 5b and d and demonstrates that retrogradely labelled CST neurons occupy the same area (in layer V) as neurons displaying upregulation of c-Jun expression. Some of the retrogradely labelled cells in Fig. 5d are shown at greater magnification in the inset to Fig. 5f. Note also that at one month, c-Jun immunoreactivity in layers II and III of the experimental side still involves areas medial and lateral to the site of LPS application with almost no c-Jun detectable in layer V (c-Jun immunoreactivity in the contralateral cortex is weak and largely confined to layers II and III: not shown). Scale bar = 500 μm and applies to Figs 5a – d and f); bar in Fig. 5e = 20 μm; bar in Fig. 5f inset = 50 μm.