Читать книгу The Esophagus - Группа авторов - Страница 46

QX‐314 is a novel lidocaine formulation that inhibits hypersensitivity by acting on the vagal afferent C fiber [101]. These fibers express a capsaicin‐responsive channel TRPV1, which is also activated by non‐selective cations such as protons. Under normal conditions, the cell membrane is impermeable; however, activation of this TRPV1 channel opens pores for QX‐314 delivery; this subsequently causes inhibition of somatosensory transmission, and therefore pain, without impairing motor function [102–105]. Hu et al. demonstrated that reflux lowers the pH sufficiently to activate the TRPV1 channel and enable QX‐314 inhibition. They also demonstrated that this effect is activated only when acid reflux occurs in the esophagus and is localized to the nociceptive afferent C type fibers. While any effect on neurogenic inflammatory response has not been well studied, the preliminary results highlight a novel pathway focus for treatment of esophageal chest pain [101].