TRH对离体脊髓内在调控运动神经元通路的影响  

Effects of thyrotropin-releasing hormone on the intraspinal regulation pathway at spinal cord motoneurons in vitro

作　　者：漆黎明 汪萌芽[1] QI Liming;WANG Mengya(Cell Electrophysiology Laboratory,Wannan Medical College,Wuhu 241002,China)

机构地区：[1]皖南医学院细胞电生理研究室,安徽芜湖241002

出　　处：《皖南医学院学报》2022年第1期5-9,共5页Journal of Wannan Medical College

基　　金：国家自然科学基金项目(31271155)。

摘　　要：目的:探讨促甲状腺激素释放激素(TRH)对脊髓内在调控运动神经元(MN)通路激活诱发的兴奋性突触后电位(EPSP)的影响。方法:选用8~14日龄的新生SD大鼠制备脊髓切片,应用脊髓切片MN细胞内记录技术,观察TRH对MN膜电学特性及同侧中央管周围区(iPCC)电刺激诱发的EPSP(iPCC-EPSP)的影响。结果:对25个MN灌流0.2μmol/L TRH,其静息电位从(-66.07±3.36)mV变化至(-58.14±4.99)mV,显示可产生去极化反应(P<0.01),其作用具有浓度依赖性,并伴有膜电阻增大(P<0.01)且可增加MN的放电频率。对18个MN给予0.2μmol/L TRH后除可产生去极化外,还可致使iPCC-EPSP产生锋电位发放,或使iPCC-EPSP的幅度从(2.41±1.02)mV增大至(3.34±1.29)mV(P<0.01)、曲线下面积从(44.58±27.11)mV·ms增大至(72.13±41.84)mV·ms(P<0.01)、时程从(47.67±17.59)ms延长至(69.00±24.96)ms(P<0.01)。结论:TRH具有易化iPCC-EPSP的作用,可以增强脊髓iPCC内在调控通路而调节MN的活动。Objective:To investigate the effects of thyrotropin-releasing hormone(TRH)on excitatory postsynaptic potential(EPSP)in motoneurons(MN)evoked by intraspinal regulation pathway.Methods:Neonatal SD rats(8-14 days old)were used to prepare transverse spinal cord slices.Intracellular recording technique for MN was used to observe the effects of TRH on the electrical properties of MN and EPSP evoked by ipsilateral pericentral canal(iPCC)electrical stimulation(iPCC-EPSP).Results:After perfusion with 0.2μmol/L TRH in 25 MN,the resting potential was changed from(-66.07±3.36)mV to(-58.14±4.99)mV,which indicated depolarization(P<0.01).The induced effects were in concentration-dependent manner,with increased membrane resistance and firing frequency of MN.In addition to a depolarization,bath of 0.2μmol/L TRH in 18 MN also induced spike discharges of iPCC-EPSP,or resulted in enhanced amplitude from(2.41±1.02)mV to(3.34±1.29)mV(P<0.01)as well as area under curve from(44.58±27.11)mV·ms to(72.13±41.84)mV·ms(P<0.01),and duration from(47.67±17.59)ms to(69.00±24.96)ms(P<0.01)of iPCC-EPSPs.Conclusion:TRH can facilitate iPCC-EPSP to modulate the MN activity by influencing the intraspinal regulation pathway from iPCC to MN.

关 键 词：促甲状腺激素释放激素 脊髓 运动神经元 同侧中央管周围区 兴奋性突触后电位 

分 类 号：R-332[医药卫生] R338.21