Photochemical model

This is a neuropathy model induced by chemical dye material and laser light. Under appropriate anesthesia, the sciatic nerve of the rodent is exposed under the laser light for certain time after chemical dye material intravenous injection. All animals are allowed to recover from surgery for at least 7 days. A decrease of pressure threshold of the ipsilateral paw comparing with baseline (before surgery) indicates a neuropathic pain (allodynia) produced. Effective antiallodynia agents will bring the decreased threshold toward baseline or completely reverse it.