Interleukin-10 prevents transition of a physiological inflammatory reaction to a pathological state that may result in neuropathic pain. We studied bilateral changes of IL-10 in L4–L5 and C7–C8 dorsal root ganglia (DRG) after a chronic constriction injury (CCI) of spinal nerves or the sciatic nerve. Rats were left to survive for 1,3,7 or 14d, sham-operated for 3 or 14 d. IL-10 was detected by immunohistochemical staining and measured using ELISA analysis. Unilateral CCI induced a transient bilateral elevation in IL-10 not only in the homonymous lumbar but also in the heteronymous cervical DRG. Sham operations also induced bilateral elevation of IL-10 in both homonymous and heteronymous DRG. Our experiments revealed that the more proximal is a nerve injury the more rapid is the initial increase and slower the subsequent decrease of IL-10 in DRG. Changes of IL-10 in nonassociated DRG could be related to a general neuroinflammatory reaction of the nervous system to injury and thereby promote potential of the DRG neurons for regenerating their axons following a conditioning lesion.