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MiR-1306-3p directly activates P2X3 receptors in primary sensory neurons to induce visceral pain in rats.

ABSTRACT:

Abstract

Mounting evidence indicates that microRNAs (miRNAs) play critical roles in various pathophysiological conditions and diseases, but the physiological roles of extracellular miRNAs on the disease-related ion channels remain largely unknown. Here, we showed that miR-1306-3p evoked action potentials and induced inward currents of the acutely isolated rat dorsal root ganglion (DRG) neurons. The miR-1306-3p-induced effects were significantly inhibited by A317491, a potent inhibitor of the P2X3 receptor (P2X3R), or disappeared after the knockdown of P2X3Rs in DRG neurons. We further identified R180, K315, and R52 as the miR-1306-3p interaction sites on the extracellular domain of P2X3Rs, which were distinct from the orthosteric ATP-binding sites. Intrathecal injection of miR-1306-3p produced visceral pain but not somatic pain in normal control rats. Conversely, intrathecal application of a miR-1306-3p antagomir and A317491 significantly alleviated visceral pain in a rat model of chronic visceral pain. Together, our findings suggest that miR-1306-3p might function as an endogenous ligand to activate P2X3Rs, eventually leading to chronic visceral pain.

SUBMITTER: Wu YY

PROVIDER: S-EPMC10281022 | biostudies-literature | 2023 Jul

REPOSITORIES: biostudies-literature

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miR-1306-3p directly activates P2X3 receptors in primary sensory neurons to induce visceral pain in rats.

Wu Yan-Yan YY Wang Qian Q Zhang Ping-An PA Zhu Cheng C Xu Guang-Yin GY

Pain 20221222 7

<h4>Abstract</h4>Mounting evidence indicates that microRNAs (miRNAs) play critical roles in various pathophysiological conditions and diseases, but the physiological roles of extracellular miRNAs on the disease-related ion channels remain largely unknown. Here, we showed that miR-1306-3p evoked action potentials and induced inward currents of the acutely isolated rat dorsal root ganglion (DRG) neurons. The miR-1306-3p-induced effects were significantly inhibited by A317491, a potent inhibitor of ...[more]

PMID: 36633528

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