Induction of Neuropathic Pain in a Rat Model by Constriction of the Infraorbital Nerve

Secure an anesthetized rat with a shaved head in a stereotaxic frame. Apply ointment to the eyes to prevent drying and cover with a surgical drape

Disinfect the head and incise to expose the skull.

Using a dissection microscope, visualize one of the eye orbits, the bony cavity in the skull that houses the eye.

Deflect the surrounding soft tissues to expose the infraorbital nerve, which transmits sensory signals from the face to the brain.

Tie two ligatures around the infraorbital nerve to constrict it and induce nerve damage.

Suture the scalp incision and allow the rat to recover.

Following the nerve constriction, damaged neurons release signaling molecules that recruit immune cells.

These immune cells release mediators that bind to nearby intact nociceptors, sensory neurons that transmit pain.

This mediator binding sensitizes the nociceptors, increasing neuronal excitability and generating pain signals that travel to the brain, contributing to neuropathic pain.

In preparation, cut two six-centimeter pieces of 5-0 chromic gut ligature. Store them in a dish of sterile saline so that they do not stiffen up. After confirming that the rat is anesthetized by the absence of a reflex response, be