TRPC3 Is Dispensable for β-Alanine Triggered Acute Itch

Area of Science:

• Neuroscience
• Molecular Biology
• Dermatology

Background:

• Pruritic (itchy) stimuli detection involves receptors and channels on primary sensory neurons.
• The G protein-coupled receptor (GPCR) MRGPRD is a molecular receptor for the itch-inducing chemical beta-alanine, found on specific mouse non-peptidergic nociceptors.
• The downstream electrical signaling channels activated by MRGPRD remain largely unknown.

Purpose of the Study:

• To investigate the role of the canonical transient receptor potential C3 (TRPC3) channel in the MRGPRD signaling pathway.
• To determine if TRPC3 functions as a downstream channel mediating beta-alanine-induced itch.

Main Methods:

• Utilized TrpC3 null mice to assess behavioral responses to beta-alanine.
• Examined beta-alanine-induced calcium influx in cultured dorsal root ganglion (DRG) neurons from TrpC3 null and wild-type mice.

Main Results:

• TrpC3 null mice exhibited normal itch responses to beta-alanine.
• Beta-alanine-triggered calcium influx in DRG neurons was not significantly different between TrpC3 null and wild-type mice.
• TRPC3 is highly expressed in MRGPRD+ nociceptors, but its function in this pathway was not essential.

Conclusions:

• Mouse TRPC3 is dispensable for beta-alanine-induced acute itch.
• TRPC3 does not appear to function as a critical downstream channel in the MRGPRD signaling pathway for beta-alanine itch.