Figure 5.
Enhanced expression of TNF-α and IL-1β in the RVM at 14 d after CCI-ION. A, Western blots illustrating that the levels of TNF-α (left) and IL-1β (right) are increased in the RVM in CCI-ION rats compared with sham-operated rats (*p < 0.05; n = 3 per group). The anti-TNF-α antibody identifies both the transmembrane TNF-α precursor (26 kDa) and matured TNF-α (17 kDa). Both TNF-α precursor and matured TNF-α exhibit an increase in the RVM at 14 d after CCI-ION. Error bars indicate SEM. B, Immunostaining of TNF-α and IL-1β in RVM. a, d, Low power of a tissue section at the rostral medulla level. b, e, Enlarged RVM region corresponds to the rectangle area in a and d, respectively. Compared with naive rats (b, e), there is an increase in TNF-α IR and IL-1β IR in RVM at 14 d after CCI-ION (c, f). The arrowheads indicate positively labeled cells. C, RVM tissue sections at 14 d after CCI are double stained for TNF-α (a, d; red) and GFAP (b; green) or NeuN (e; green). The arrowheads indicate positively labeled cells. Overlap of a and b reveals that the TNF-α IR is colocalized with GFAP IR in RVM cells (c; yellow, arrows), suggesting its presence in astrocytes. Overlap of d and e shows a lack of TNF-α in RVM neurons (f). D, RVM tissue sections were double stained for IL-1β (a, d; red) and GFAP (b; green) or NeuN (e; green). The arrowheads indicate positively labeled cells. Overlap of a and b reveals that the IL-1β-labeled cells are GFAP immunoreactive in RVM (c; yellow, arrows), suggesting its presence in astrocytes. Overlap of d and e shows a lack of IL-1β IR in these RVM neurons (f). Scale bars: Ba,d, 0.1 mm; Bb,c,e,f, 0.03 mm; C, D, 0.03 mm.
