Correlation of Nav1.8 and Nav1.9 Sodium Channel Expression with Neuropathic Pain in Human Subjects with Lingual Nerve Neuromas

Abstract

BackgroundVoltage-gated sodium channels Nav1.8 and Nav1.9 are expressed preferentially in small diameter sensory neurons, and are thought to play a role in the generation of ectopic activity in neuronal cell bodies and/or their axons following peripheral nerve injury. The expression of Nav1.8 and Nav1.9 has been quantified in human lingual nerves that have been previously injured inadvertently during lower third molar removal, and any correlation between the expression of these ion channels and the presence or absence of dysaesthesia investigated.ResultsImmunohistochemical processing and quantitative image analysis revealed that Nav1.8 and Nav1.9 were expressed in human lingual nerve neuromas from patients with or without symptoms of dysaesthesia. The level of Nav1.8 expression was significantly higher in patients reporting pain compared with no pain, and a significant positive correlation was observed between levels of Nav1.8 expression and VAS scores for the symptom of tingling. No significant differences were recorded in the level of expression of Nav1.9 between patients with or without pain.ConclusionsThese results demonstrate that Nav1.8 and Nav1.9 are present in human lingual nerve neuromas, with significant correlations between the level of expression of Nav1.8 and symptoms of pain. These data provide further evidence that changes in expression of Nav1.8 are important in the development and/or maintenance of nerve injury-induced pain, and suggest that Nav1.8 may be a potential therapeutic target.

Effect of duration from lingual nerve injury to undergoing microneurosurgery on improving sensory and taste functions: retrospective study

“…To determine the abundance ratio of Schwann cells, the area of immunoreactivity against anti-S100β antibodies was measured using ImageJ software in three fields of view from the central side of the traumatic neuroma to the peripheral side. The abundance ratio of Schwann cells in each sample was calculated as the average of the immunoreacted area against anti-S100β antibodies per tissue area in three fields of view [23][24][25].…”

Topical Ambroxol 20% for the Treatment of Classical Trigeminal Neuralgia – A New Option? Initial Clinical Case Observations

“…Earlier, the Na v 1.8 channel subtype also was found in trigeminal ganglia. 17 Na v 1.8 as well as the coexpressed Na v 1.7 are enriched in thin peripheral trigeminal neurons 35,36 and dorsal root ganglia (DRG), 37 but of particular importance also in gingival tissue of patients suffering from trigeminal neuralgia 8 (Table 2). Both subtypes are blocked by ambroxol.…”

A Feasibility Research on Restoration of Demyelination in Trigeminal Nerve with Transnasal Administration of BDNF/ NGF Loading on PEG-PLA Nanoparticles

“…Previous studies have found the up-regulation of Nav1.8 in trigeminal nerve [25][26][27]. As the trigeminal root is compressed, the nerve fibers are demyelinated, which induces the Nav1.8 emerge in the compressed site and leads to subthreshold membrane potential oscillation (SMPO); when the membrane potential reaches the threshold, ectopic action potentials are ignited; when these messy impulses transmit to the central, paroxysmal pain attacks [28].…”