电针调节P2X7R介导的细胞焦亡途径对骶上脊髓损伤后尿潴留型神经源性膀胱大鼠膀胱排尿功能的影响OACSTPCD

Objective To observe the effects of electroacupuncture on bladder voiding function in rats with neurogenic bladder(NB)featuring urinary retention after suprasacral spinal cord injury(SCI),and to explore the potential mechanisms of electroacupuncture in regulating the pyroptosis pathway mediated by purinergic receptor P2X ligand-gated ion channel 7(P2X7R).Methods Twelve from 48 female SD rats were randomly selected as the sham-operated group.The remaining rats were used to establish a rat model of NB featuring urinary retention by T8 complete spinal cord transection.Of the 27 successfully modeled rats,24 were randomized into model group and electroacupuncture group,with 12 rats in each group,and the remaining three model rats were reserved for experimental backups.The electroacupuncture group received intervention on the 19th day after operation for 10 consecutive days,while the other two groups were only restrained.After the intervention,urodynamic tests were first performed on the rats in each group,followed by rapid separation of bladder tissue for examination.HE staining was used to observe the morphological changes in bladder tissue;transmission electron microscopy was used to observe the ultrastructural changes of bladder tissue;TUNEL staining was used to examine cell damage in bladder tissue;ELISA was used to check the level of adenosine triphosphate(ATP)in bladder tissue;immunohistochemistry and Western blot were used to examine the protein expression levels of P2X7R,NOD-like receptor thermal protein domain associated protein 3(NLRP3),cysteinyl aspartate specific proteinase-1(Caspase-1),and interleukin-1β(IL-1β)in bladder tissue.Results Compared with the sham-operated group,the bladder leak point pressure,maximum bladder pressure,and maximum bladder capacity in the model group significantly increased(P<0.01),with bladder volume increase accompanied by urinary retention as the main manifestations.The model group rats showed significant inflammatory reaction and pathological changes in bladder tissue,with obvious swelling,deformation,and other signs of cell damage in the ultrastructure of bladder tissue,and a significantly increased cell damage rate(P<0.01).The ATP content,the positive expression and protein expression levels of P2X7R,NLRP3,Caspase-1,and IL-1β in bladder tissue significantly increased(P<0.01).Compared with the model group,the bladder leak point pressure,maximum bladder pressure,and maximum bladder capacity of the rats in the electroacupuncture group decreased(P<0.05),with milder symptoms of urinary retention and improved bladder voiding function.The electroacupuncture group showed alleviated inflammatory reaction and pathological damage,significantly improved ultrastructural changes,significantly reduced cell damage rate(P<0.01),and significantly reduced ATP content,positive expression and protein expression levels of P2X7R,NLRP3,Caspase-1,and IL-1β in the bladder tissue(P<0.01).Conclusion Electroacupuncture can effectively improve the bladder voiding function in rats with NB featuring urinary retention after suprasacral SCI,alleviate the symptoms of urinary retention,and reduce the degree of pathological damage and inflammatory response in bladder tissue.Its mechanism is related to the inhibition of the expression of pyroptosis protein in P2X7R/NLRP3 signaling pathway in bladder tissue.