[The role of immune system in inflammatory pain pathophysiology].

Despite of many years of research, the data regarding interactions between the peripheral nervous system and the immune system remain incomplete. Most discoveries concern nociceptive signaling pathways. Among pain conditions with the utmost social implications, a large percentage exhibits the inflammatory process as an underlying cause. Here the most prominent are several disorders associated with the trigeminal nerve, including migraine, trigeminal neuralgia, and temporomandibular disorders. The molecular mechanisms of the trigeminal nociceptive transmission in general, and chronic trigeminal pain in particular, are almost completely unknown. Recent studies have shown that cytokines IL-1beta, IL-6 and TNF-alpha play a very important role in the pathogenesis of the immune response within the peripheral endings of trigeminal ganglion neurons. It has also been demonstrated that some proinflammatory cytokines (e.g., IL-1beta, TNF-alpha) are capable of sensitizing nociceptive neurons. Modulation of inflammatory response can thus influence pain reaction.