P2X3 Receptor in Primary Afferent Neurons Mediates the Relief of Visceral Hypersensitivity by Electroacupuncture in an Irritable Bowel Syndrome Rat Model

Fang Zhang; Zhe Ma; Zhijun Weng; Min Zhao; Handan Zheng; Luyi Wu; Yuan Lu; Chunhui Bao; Yanan Liu; Huirong Liu; Huangan Wu

doi:10.1155/2020/8186106

P2X₃ Receptor in Primary Afferent Neurons Mediates the Relief of Visceral Hypersensitivity by Electroacupuncture in an Irritable Bowel Syndrome Rat Model

Gastroenterol Res Pract. 2020 Sep 16:2020:8186106. doi: 10.1155/2020/8186106. eCollection 2020.

Authors

Fang Zhang¹, Zhe Ma¹, Zhijun Weng¹, Min Zhao², Handan Zheng¹, Luyi Wu², Yuan Lu¹, Chunhui Bao¹, Yanan Liu¹, Huirong Liu¹, Huangan Wu¹

Affiliations

¹ Shanghai Research Institute of Acupuncture and Meridian, Shanghai University of Traditional Chinese Medicine, Shanghai, China.
² Shanghai University of Traditional Chinese Medicine, Shanghai, China.

Abstract

Background: Electroacupuncture (EA) has been confirmed effectiveness in the treatment of irritable bowel syndrome (IBS), and P2X₃ receptors in the peripheral and central neurons participate in the acupuncture-mediated relief of the visceral pain in IBS.

Objective: To reveal the neurobiological mechanism that P2X₃ receptor of colonic primary sensory neurons in the dorsal root ganglia of the lumbosacral segment is involved in the alleviation of visceral hypersensitivity by EA in an IBS rat model.

Methods: The IBS chronic visceral pain rat model was established according to the method of Al-Chaer et al. EA at the bilateral He-Mu points, including ST25 and ST37, was conducted for intervention. The behavioral studies, histopathology of colon, electrophysiology, immunofluorescence histochemistry, and real-time polymerase chain reaction assays were used to observe the role of P2X₃ receptor in the colon and related DRG in relieving visceral hypersensitivity by EA.

Results: EA significantly reduced the behavior scores of the IBS rats under different levels (20, 40, 60, 80 mmHg) of colorectal distention stimulation and downregulated the expression levels of P2X₃ receptor protein and mRNA in colon and related DRG of the IBS rats. EA also regulated the electrical properties of the membranes, including the resting membrane potential, rheobase, and action potential of colon-associated DRG neurons in the IBS rats.

Conclusion: EA can regulate the P2X₃ receptor protein and mRNA expression levels in the colon and related DRG of IBS rats with visceral pain and then regulate the excitatory properties of DRG neurons.