前列腺炎疼痛对背根神经节细胞兴奋性的影响及P2X_3表达的变化

Excitability changes of DRG neurons and expression of P2X_3 receptor in DRG neurons affected by prostatitis induced by CFA

目的探讨慢性前列腺炎疼痛对P2X介导的背根神经节(dorsal root ganglion,DRG)细胞兴奋性的影响及P2X3受体表达的变化。方法采用膜片钳全细胞记录技术、蛋白免疫印迹(W estern blot)技术对急性分离的DRG细胞ATP所激发的自发放电反应及P2X3蛋白表达进行检测。结果对照组、炎症疼痛3 d组神经元膜电位波动幅度都较小,不能产生自发性动作电位。炎症疼痛10 d组神经元膜电位波动明显,部分神经元膜电位波动幅度较大,可以达到阈值产生自发动作电位,约有10.26%(4/39)神经元出现自发性电活动。炎症3 d后P2X3蛋白表达有所增加,但与对照组相比无显著性差异,炎症10 d后P2X3蛋白表达与对照组相比显著增加。结论相应节段背根节神经元兴奋性及P2X3受体表达的增加可能在前列腺炎疼痛的产生和维持中起重要作用。

Objective To explore excitability change of P2X receptor-mediated DRG neurons and expression of P2X3 receptor in the DRG neurons affected by prostatic inflammation. Mothods ATP-evoked spontaneous firing and the expression of P2X3receptor in the DRG neurons in the L6-S1 spinal cord were investigated by whole-cell patch clamp techniques, Western blotting on day 3, 10 after Complete Freund＇ s adjuvant （CFA） irritation of the rat prostate. Rosults Membrane potential of DRG neurons fluctuated spontaneously under current clamp. Membrane potential of neurons of control group and 3-day CFA irritation group were under threshold potential, and all recorded neurons had not action potential. However, 4 of 39 neurons （ 10.26% ） showed spontaneous action potential at membrane potential on day 10 after CFA irritation of prostate. Expression of P2X3 receptor increased significantly on day 10 after CFA irritation of the prostate by Western blotting. Conclusion The increase of expression and sensitivity of P2X3 receptor may play important roles in the development and maintenance of the pain owing to prostatic inflammation.