I am a
Home I AM A Search Login

Papers of the Week


Papers: 14 Dec 2019 - 20 Dec 2019


Animal Studies


2019 12 12


Nat Commun


10


1

TRPV1 activity and substance P release are required for corneal cold nociception.

Authors

Li F, Yang W, Jiang H, Guo C, Huang AJW, Hu H, Liu Q
Nat Commun. 2019 12 12; 10(1):5678.
PMID: 31831729.

Abstract

As a protective mechanism, the cornea is sensitive to noxious stimuli. Here, we show that in mice, a high proportion of corneal TRPM8 cold-sensing fibers express the heat-sensitive TRPV1 channel. Despite its insensitivity to cold, TRPV1 enhances membrane potential changes and electrical firing of TRPM8 neurons in response to cold stimulation. This elevated neuronal excitability leads to augmented ocular cold nociception in mice. In a model of dry eye disease, the expression of TRPV1 in TRPM8 cold-sensing fibers is increased, and results in severe cold allodynia. Overexpression of TRPV1 in TRPM8 sensory neurons leads to cold allodynia in both corneal and non-corneal tissues without affecting their thermal sensitivity. TRPV1-dependent neuronal sensitization facilitates the release of the neuropeptide substance P from TRPM8 cold-sensing neurons to signal nociception in response to cold. Our study identifies a mechanism underlying corneal cold nociception and suggests a potential target for the treatment of ocular pain.