过表达Pdk4对脊神经结扎小鼠线粒体及神经元电生理活性的影响  

Effects of Pdk4 overexpression on mitochondrial and neuronal electrophysiological activities in spinal nerve ligation mice

作　　者：郑军凡 林爱金 桂锋 陈述荣 陈昕 ZHENG Junfan;LIN Aijin;GUI Feng;CHEN Shurong;CHEN Xin(The First Department of Rehabilitation,Fuzhou Second General Hospital,Fuzhou,Fujian 35ooo7,China)

机构地区：[1]福建省福州市第二总医院康复一科,福州350007

出　　处：《福建医药杂志》2025年第1期73-77,共5页Fujian Medical Journal

基　　金：2023年福州市卫健系统科技计划中青年科研项目(2023-S-wq10);福建省创伤骨科急救与康复临床医学研究中心项目(2020Y2014)。

摘　　要：目的考察过表达丙酮酸脱氢酶激酶4(Pdk4)对脊神经结扎小鼠线粒体及神经元电生理活性的影响,进一步揭示神经病理性疼痛的发病机制。方法选用雄性C57BL/6小鼠构建脊神经结扎(SNL)模型并分为假手术组、SNL模型组及SNL模型+Pdk4过表达组。SNL模型+Pdk4过表达组采用脊髓背角内病毒注射法注射Pdk4过表达病毒。采用不同规格细丝检测足底机械性疼痛阈值;采用Western blot测定小鼠脊髓背角Pdk4、LC3-Ⅱ、LC3-Ⅰ蛋白表达;采用电子显微镜观察线粒体形态;采用膜片钳技术测定神经元电生理指标。结果过表达Pdk4后,小鼠机械性疼痛阈值降低(P<0.05);透射电镜观察显示线粒体肿胀更明显,嵴结构进一步紊乱且部分出现空泡化;Pdk4蛋白表达量升高(P<0.05),LC3-Ⅱ/LC3-I比值升高(P<0.05);小鼠脊髓背角内神经元自发性兴奋性突触后电流增大,动作电位释放个数增多,基强度降低,输入阻抗降低(P<0.05)。结论Pdk4表达上调使小鼠疼痛阈值降低,增加疼痛敏感性,可能与脊髓背角线粒体形态变化、自噬相关信号通路激活及神经元兴奋性增强有关。Objective To investigate the effects of Pdk4 overexpression on mitochondrial and neuronal electrophysiological activities in spinal nerve ligation mice,and to further reveal the pathogenesis of neuropathic pain.Methods Male C57BL/6 mice were selected to establish the spinal nerve ligation model,and they were divided into the sham-operation group,the SNL model group,and the SNL model+Pdk4 overexpression group.The SNL model+Pdk4 overexpression group was injected with Pdk4-overexpressing virus by intraspinal dorsal horn viral injection.Filaments of different specifications were used to detect the plantar mechanical pain threshold.Western blot was used to determine the protein expressions of Pdk4,LC3-Ⅱ,and LC3-Ⅰin the spinal dorsal horn of mice,Electron microscope was used to observe the mitochondrial morphology.The patch-clamp technique was used to measure the neuronal electrophysiological indexes.Results After Pdk4 overexpression,the mechanical pain threshold of mice decreased(P<0.05).Transmission electron microscopy showed more obvious mitochondrial swelling,further disorder of the cristae structure,and partial vacuolization.The expression level of Pdk4 protein increased(P<0.05),and the ratio of LC3-Ⅱ/LC3-Ⅰincreased(P<0.05).In the spinal dorsal horn of mice,the spontaneous excitatory postsynaptic current of neurons increased,the number of action potential releases increased,the rheobase decreased,and the input impedance decreased(P<0.05).Conclusion The up-regulation of Pdk4 expression reduces the pain threshold of mice and increases pain sensitivity,which may be related to the morphological changes of mitochondria in the spinal dorsal horn,the activation of autophagy-related signaling pathways,and the enhancement of neuronal excitability.

关 键 词：脊神经 线粒体 神经元 电生理 

分 类 号：R329.2[医药卫生—人体解剖和组织胚胎学]