Changes in TRP Channels Expression in Painful Conditions

Mahendra Bishnoi,Louis S Premkumar

doi:10.2174/1876386301306010010

Abstract

Over the last fifteen years after the successful cloning of the first nociceptive Transient Receptor Potential (TRP) channel, TRP Vanilloid 1, other members of the TRP channel family have been cloned, characterized and implicated in different modalities of pain. Tremendous progress has been made with regard to the specific role of these TRP channels in nociception using electrophysiological and molecular methods, along with behavioral models combined with gene disruption techniques. This review summarizes the evidence supporting the role of TRP channels (TRP Vanilloid 1, TRP Vanilloid 2, TRP Vanilloid 3, TRP Vanilloid 4, TRP Ankyrin 1, TRP Melastatin 2, TRP Melastatin 3, TRP Melastatin 8, TRP Mucolipin 3 and TRP Canonical 1, 6) involved in nociception. The review also highlights the current status and future avenues for developing TRP channel modulators as analgesic agents.

Highlights

"Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage"
We suggest that TRANSIENT RECEPTOR POTENTIAL VANILLOID 4 (TRPV4), TRPC6 and TRPC1 participate in mechanical hyperalgesia and primary afferent nociceptors sensitization
Members of the Transient Receptor Potential (TRP) channel family are constantly being added to the list of nociceptive TRP channels as their relevance is revealed by their expression pattern, gene disruption studies and specific antagonists

Summary

Introduction

"Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage". TRPV1 expressed at the peripheral terminals of nociceptors and is activated by heat (>42oC) and responsible for transmitting acute noxious thermal sensation and inflammatory thermal hypersensitivity. Both peripheral and central nerve terminals at the spinal cord can be targeted to induce pain relief by TRPV1 agonists [11].

Results

Conclusion