Usefulness of Current Withdrawal Threshold on Evaluation of the Neuropathic Pain in Animal Model

Song, Eun Beom; Yang, Jung Hoon; Kang, Yoon Kyoo; Kim, Sei Joo

Abstract

OBJECTIVE
To evaluate usefulness of the current withdrawal threshold (CWT) on evaluation of the neuropathic pain in animal model. METHOD: Surgical neuropathy was induced in 40 Sprague-Dawley rats. Fourteen days after the surgery, neuropathic rats were evaluated by von Frey hair. The CWT was determined by various stimulus intensities which induce the tail-withdrawal response or vocalization of rats. The experimental group was compared with the control group by CWT. Then the experimental group was subdevided to two groups. The experimental group 1 was injected with beta-methasone 0.1 mg/kg, intra-peritoneally and experimental group 2 was injected with normal saline with the same amount as steroid. The CWT of two experimental subgroups were measured before and 30 minutes after injections.
RESULTS
The experimental group showed significant decrease of the CWT compared with the control group after the neuropathic pain was induced. The CWT of experimental group 1 was increased after steroid administration (p<0.01).
CONCLUSION
This preliminary study suggests that the measurement of CWT would be an useful tool to study the neuropathic pain in experimental animal model.