Ketamine suppresses c-fos expression in dorsal horn neurons after acute constrictive sciatic nerve injury in the rat.

Fos immunoreactivity within the spinal cord in a model of neuropathic pain was studied. Dorsal horn neurons in laminae I and II exhibited selective expression within the tibial, peroneal and posterior cutaneous nerve territories which, in turn, was suppressed during ketamine but not halothane anesthesia. Fos immunoreactive neurons have a unique response pattern to neuropathic pain which is sensitive to ketamine.