Immunofluorescence staining for interleukin-6 receptor (IL-6R). Representative sections of (A,C,E) lumbar and (B,D,F) cervical dorsal root ganglia (DRG) incubated for IL-6R immunohistochemical staining. Sections of L4 and C7 DRG removed from (A,B) naive rats and (C–F) from rats 3 days after chronic constriction injury (CCI) of the sciatic nerve. Immunofluorescence staining for IL-6R was increased in the large (thick arrows), medium, and small (thin arrows) neurons of lumbar and cervical DRG from both ipsilateral (DRGi) and contralateral (DRGc) sides of CCI rats compared with naive rats (DRGn). Increased IL-6R immunofluorescence was also present in satellite glial cells (SGC) of lumbar DRG ipsilateral to CCI (C, arrowhead). The sections were treated with rabbit polyclonal anti-IL-6R antibody and tetramethyl rhodamine isothiocyanate (TRITC)-conjugated donkey anti-rabbit secondary antibody under identical conditions. Scale bars = 80 μm.