Reactive oxygen species-specific characteristics of transient receptor potential ankyrin 1 receptor and its pain modulation

Transient receptor potential ankyrin 1 (TRPA1) receptors are major polymodal nociceptors that generate primary pain responses in the peripheral nerve endings of the dorsal root ganglion neurons. Recently, we reported that the activation of TRPA1 receptors by reactive oxygen species (ROS) signaling, which is triggered by Ca2+ influx through T-type Ca2+ channels, contributes to prolonged pain responses induced by jellyfish toxin. In this review, we focus on the characteristics of the TRPA1 receptor involved in intracellular signaling as a secondary pain modulator. Unlike other transient receptor potential receptors, TRPA1 receptors can induce membrane depolarization by ROS without exogenous stimuli in peripheral and central sensory neurons. Therefore, it is important to identify the functional characteristics of TRPA1 receptors to understand pain modulation under several pathogenic conditions such as neuropathic pain syndromes and autoimmune diseases, which are mediated by oxidative signaling to cause chronic pain in the sensory system.