Development of Neuropathic Pain Model with 1% Phenol Injection in Rat Sciatic Nerve

ABSTRACT

OBJECTIVE: The purpose of this study is to develop a new neuropathic pain model in the rat. METHOD: Each male adult rat was anesthetized and the sciatic nerve was exposed. Each exposed nerve was injected with 0.03 cc of 1% phenol solution. Normal saline 0.03 cc was injected to the placebo group. Rats were tested for the presence of mechanical allodynia by von Frey hair. Spontaneous pain behavior (paw shaking, paw elevation) was examined for 5 minutes in the cage. RESULTS: Phenol injected group developed allodynia after the second post-injection day for up to 1 month. Allodynia was also observed in the contralateral legs of phenol injected group. The control group did not develop allodynia. Spontaneous pain behavior was not observed in either group. CONCLUSION: Neuropathic pain model was developed by 1% phenol solution injection to the rat sciatic nerve. This study suggests an easier method for making the neuropathic pain model.