Table 1 lists a brief synopsis of experimental nociceptive/pain models of arthritis, formalin injection, colitis, and inflammatory bowel syndrome (IBS) that directly assess GluN1 subunit expression and function and expand the pain models and conditions. Studies demonstrating increased NMDA receptor agonists or inflammatory mediator levels, and preincubation with enhancing agents are also included. A comprehensive review, including NMDA receptor activation in nociceptive models for orofacial pain, has been recently published [54]. The gene discussed is GRIN1; the disease is colitis.