Involvement of trigeminal ganglionic Na_v1.7 in hyperalgesia of inflamed temporomandibular joint is dependent on ERK1/2 phosphorylation of glial cells in rats

Abstract

Trigeminal ganglionic Nav 1.7 has an important function in the hyperalgesia of the inflamed TMJ, which is dependent on the communication with the satellite glials.

A new hypothesis of sex-differences in temporomandibular disorders: Estrogen enhances hyperalgesia of inflamed TMJ through modulating voltage-gated sodium channel 1.7 in trigeminal ganglion?

“…In addition, the nociceptor-specific knockout of Nav1.7 [19] and the knock-down of Nav1.7 [20] in primary afferents abrogate inflammatory hyperalgesia. Our previous study also found trigeminal ganglionic Nav1.7 is involved in hyperalgesia of inflamed TMJ [22]. These findings strongly suggest that Na v 1.7 plays an important role in pain.…”

“…A nucleotide polymorphism in Nav1.7 alters pain perception in patients with either knee or hip osteoarthritis [21]. Furthermore, our previous study also showed that trigeminal ganglionic Nav1.7 was involved in hyperalgesia of inflamed TMJ [22].…”

“…The vehicle group and Nav1.7 antibody group will be injected with 50 µl of CFA into the bilateral TMJs to induce TMJ inflammation. The Nav1.7 antibody group will be microinjected with Nav1.7 antibody into the trigeminal ganglion performed as previously described [22]. Then head withdrawal threshold and food intake (another indicator for TMJ nociception [3]) will be measured.…”

Differential Diagnostics of Pain in the Course of Trigeminal Neuralgia and Temporomandibular Joint Dysfunction

“…The increase in the amplitude of vibrations damages the permeability of ion channels, leading to nerve injury. The disorder is characterized by recurrent, paroxysmal attacks of sudden, intense, and piercing pain within the region supplied by the trigeminal nerve, comparable to an electric shock [5–7, 9–19, 30]. …”

“…Neuralgia of this type may be a symptom of numerous diseases within the region of the posterior cranial fossa, such as basal tumors or cerebellopontine angle tumors. This type of neuralgia may also be observed in alcohol, mercury, or nicotine intoxication [8–13, 15, 18, 30]. …”