Chronic Constriction of the Sciatic Nerve and Pain Hypersensitivity Testing in Rats

The overall goal of this procedure is to perform chronic constriction, injury of the sciatic nerve, a commonly used rodent model of neuropathic pain, and quantitatively measure the resulting pain behaviors. This is accomplished by first placing four chromic gut ligatures around the exposed sciatic nerve at mid thigh level to create a constriction injury to the sciatic nerve. Next, monitor pain behaviors in the hind paw at desired time points by quantitatively measuring paw withdrawal threshold to mechanical stimulus using a von fray anthes and paw withdrawal latency to thermal stimulus using a plantar analgesia meter.

Ultimately results can be obtained that show the existence of mechanical and thermal pain, hypersensitivity of the injured hind paw through the measurement of evoked withdrawal responses to both mechanical and thermal stimuli. This method of peripheral nerve injury first developed by bene and Z can help us answer key questions in the field of chronic pain, such as what are the peripheral and central mechanisms by which neuropathic pain is generated. The implications of this technique extend toward therapy of neuropathic pain because this model provides the basis to examine novel strategies to reduce pain hypersensitivity.