Objective:To investigate the role of serotonin reuptake transporter(SERT)and {2}2X3 receptor of dorsal root ganglion(DRG)in regulating visceral hypersensitivity of rats with irritable bowel syndrome(IBS)by electroacupuncture(EA).Methods:Male Sprague-Dawley and SERT^(-/-)rats were subjected to preparing IBS visceral hypersensitivity models with 2,4,6-trinitrobenzene sulfonic acid(TNBS)enema.Three weeks post-modeling,interventions including EA,intrathecal injection,and EA plus intrathecal injection were applied,respectively.Hematoxylin-eosin staining and abdominal withdrawal reflex(AWR)score were used to confirm the successful establishment of the IBS model.AWR score,whole-cell patch clamp technique,and Western blotting assay were used to evaluate the changes in visceral pain sensitivity,electrophysiological properties of DRG neurons,and the expression of DRG {2}2X3 receptor and SERT in IBS rats.Results:Compared to the model group,the AWR score in the EA group decreased significantly({2}<0.05),the resting membrane potential({2}<0.05)and the number of action potentials({2}<0.05)of DRG neurons reduced,and the baseline intensity increased({2}<0.05);additionally,the expression of {2}2X3 receptor in DRG decreased({2}<0.01),and the SERT expression increased({2}<0.05).Compared to the {2}2X3 receptor agonist group,the SERT protein expression in DRG was higher in the EA group.In SERT^(-/-)rats,the {2}2X3 receptor expression in DRG increased in the EA group compared to the model group({2}<0.01).Conclusion:EA modulates the electrophysiological characteristics of intestinal primary sensory neurons by regulating the expression of SERT and {2}2X3 receptor in DRG of IBS rats.This modulation may contribute to the mechanism by which EA alleviates peripheral sensitization of visceral pain in IBS rats.
