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Updated: Jul 20, 2026

Characterizing Modulators of Protease-Activated Receptors with a Calcium Mobilization Assay Using a Plate Reader
Published on: May 24, 2024
Agonist of proteinase-activated receptor 2 increases painful behavior produced by alpha, beta-methylene adenosine
Wan-Jun Zhu1, Yi Dai, Tetsuo Fukuoka
1Department of Anatomy and Neuroscience, Hyogo College of Medicine, Nishinomiya, Hyogo, Japan.
Abstract:
Proteinase-activated receptor (PAR) 2 is expressed in a subset of primary afferent neurons and is involved in inflammatory nociception. The P2X3 ion channel is localized on nociceptors of sensory neurons. Using immunohistochemistry, we showed that many P2X3s are co-expressed with the PAR2 in rat dorsal root ganglia neurons. Nocifensive behavior induced by alphabeta-methylene adenosine 5'-triphosphate (ATP) injection to the hind paw was significantly augmented after the application of PAR2 agonists. Fos expression induced by the alphabeta-methylene ATP injection in dorsal horn neurons was also increased after the pre-application of PAR2 agonists. These findings indicate that PAR2 agonists may potentiate the sensitivity of P2X3 ion channel to noxious stimuli, and the interaction between PAR2 and P2X3 may be an important mechanism underlying inflammatory pain.
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