TRP Ion Channels and Temperature Sensation

Abstract

The abilities to sense environmental and internal temperatures are required for survival, both for maintenance of homeostasis and for avoidance of tissue-damaging noxious temperatures. Vertebrates can sense external physical stimuli via specialized classes of neurons in the peripheral nervous system that project to the skin. Temperature-sensitive neurons can be divided into two classes: innocuous thermosensors (warm or cool) and noxious thermonociceptors (hot or cold). ThermoTRPs, a subset of the transient receptor potential family of ion channels, which are expressed in sensory nerve endings and in skin, respond to distinct thermal thresholds. In this review, we examine the extent to which thermoTRPs are responsible for providing a molecular basis for thermal sensation.

Somatosensory neuron types identified by high-coverage single-cell RNA-sequencing and functional heterogeneity

“…A heterogeneity analysis of signaling molecules in neuron clusters as well as previous reports implies the functionalities of these neuron clusters ( Figure 5A; Supplementary information, Data S1). TRP channels are involved in temperature sensing [12]. Trpv1 is expressed strongly in C1-1 and moderately in C1-2 and C2-1 ( Figure 5A; Supplementary information, Figure S8B).…”

“…Defined nociceptor subtypes have been termed C-fiber (C-) or Aδ-fiber (A-) mechanoheat nociceptors (MHNs), mechanical nociceptors (MNs), mechanically insensitive (MI) or sensitive afferents, and mechanoheat-cold nociceptors [5,6]. The molecular properties of DRG neurons have been extensively studied, including their expression of various receptors and ion channels such as neuropeptide Y (NPY) receptors [7], MAS-related G-protein-coupled receptors (MRGPRs) [8,9], voltage-gated Na + channels [10], transient receptor potential (TRP) channels [11,12], ATP receptors [13], acid-sensing ion channels (ASICs) [14,15] and tyrosine kinase receptors (TRKs) [16]. Gene expression profiles of DRG tissue have been also analyzed by microarray and RNA-sequencing (RNA-seq) techniques [17,18].…”

Gabapentin Attenuates the Activation of Transient Receptor Potential A1 by Cinnamaldehyde

“…Temperature-sensitive transient receptor potential ion channels (thermoTRPs) have been discovered in the peripheral sensory organs (TRPV1-4, TRPM8 and TRPA1) (Dhaka et al, 2006). Among the thermoTRPs, TRPA1 channel is emerging as an important pain sensor that is able to detect environmental, inflammatory or physical stimuli.…”

Structure of TRPV1 channel revealed by electron cryomicroscopy

“…These channels have diverse properties with respect to gating and ion selectivity, and in the few cases where they are known, diverse physiological functions (4). Some TRP channels respond to physical stimuli such as heat, cold, or osmotic stress, and some are gated by pH changes in the physiological range (5,6). They are thought in many cases to be coupled to signaling by G protein-coupled receptors, as in invertebrate vision, where they serve as the transduction channels (7).…”