Wallerian degeneration after crush or chronic constriction injury of rodent sciatic nerve is associated with a depletion of endoneurial interleukin-10 protein.

We used enzyme-linked immunoassay (ELISA), immunohistochemistry (IHC), and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) to determine whether interleukin (IL)-10 protein is changed after unilateral crush or chronic constriction injury (CCI) of mouse or rat sciatic nerve and whether IL-10 protein and mRNA are differentially regulated. In the mouse sciatic nerve, IL-10 protein declined rapidly to 10-20% of baseline early after crush or CCI, while the IL10 mRNA was up-regulated with a maximum on Days 1 and 3. In the rat sciatic nerve, IL-10 protein was significantly reduced on Day 3 after CCI, and IL-10 mRNA was up-regulated in both models. These results suggest that changes of the local cytokine network during wallerian degeneration include an early deficiency of the antiinflammatory cytokine IL-10 despite up-regulation at the mRNA level.