Objective
To investigate the analgesic effect of needle electrical stimulation (NES) according to the electrode placement in acute arthritic rat model. Method: Male Sprague-Dawley rats (120 rats, 250⁑50 g) were injected with a mixture of 3% carrageenan and 3% kaolin into the right knee joint. Rats were randomly assigned into one of four groups: Group I, control group (n=30); Group II, arthritic limb-induced control group (n=30); Group III, NES application group on the ipsilateral arthritic limb (n=30); Group IV, NES application group on the contralateral arthritic limb (n=30). We applied the NES (2 Hz, 200μs, 20 min) to group III and IV. We assessed the change of paw withdrawal latency (PWL) and the immunoreactivity of c-fos by immunohistochemistry at baseline, 4, 8, 12 and 24 hours after induction of arthritis. Results: NES was more effective in Group III and IV than group II 8 hours after the induction of arthritis (p＜0.001) based on the results of PWLs and c-fos immunoreactivity. The analgesic effects of Group III were greater than those of group IV (p＜0.001). Conclusion: Contralateral NES on arthritic limb reduced pain in arthritic rat model as effectively as ipsilateral NES. (J Korean Acad Rehab Med 2007; 31: 143-149)
