Western blot analysis of interleukin (IL)-6 protein levels. Western blot analysis of IL-6 protein levels in dorsal root ganglia (DRG) at (A) L4-L5 and (B) C7-C8 from naive rats (0), rats with unilateral chronic constriction injury (CCI) of the sciatic nerve after 1, 3, 7, and 14 days, and rats with sham surgery after 1 and 3 days. Upper panels illustrate representative western blotting bands of ipsilateral (I) and contralateral (C) DRG from two naive, two CCI, and two sham rats for each period of survival. Equal loading of proteins was confirmed by α-tubulin staining (Tu). Lower panels show mean density ± SD of individual IL-6 protein bands in triplicate analysis after normalization to tubulin, with the mean density of the IL-6 bands from naive DRG taken as 1.