Electroacupuncture diminishes P2X2 and P2X3 purinergic receptor expression in dorsal root ganglia of rats with visceral hypersensitivity

Electroacupuncture at Shangjuxu (ST37) and Tianshu (ST25) can improve visceral hypersensitivity in rats. Colorectal distension was used to establish a rat model of chronic visceral hypersensitivity. Immunohistochemistry was used to detect P2X₂ and P2X₃ receptor expression in dorsal root ganglia from rats with chronic visceral hypersensitivity. Results demonstrated that abdominal withdrawal reflex scores obviously increased following establishment of the model, indicating visceral hypersensitivity. Simultaneously, P2X₂ and P2X₃ receptor expression increased in dorsal root ganglia. After bilateral electroacupuncture at Shangjuxu and Tianshu, abdominal withdrawal reflex scores and P2X₂ and P2X₃ receptor expression decreased in rats with visceral hypersensitivity. These results indicated that electroacupuncture treatment improved visceral hypersensitivity in rats with irritable bowel syndrome by reducing P2X₂ and P2X₃ receptor expression in dorsal root ganglia.