HCN通道对大鼠脊髓背角神经元P2X受体功能的调节作用  

HCN channels modulate P2X receptor function in cultured rat spinal dorsal horn neurons

作　　者：杨舒蕾 雷晓露 刘晓红 Yang Shulei;Lei Xiaolu;Liu Xiaohong(Department of Physiology,Henan Vocational University of Science and Technology,Zhoukou Henan 466000,China;Department of Physiology,Zunyi Medical University,Zunyi Guizhou 563099,China)

机构地区：[1]河南科技职业大学生理学教研室,河南周口466000 [2]遵义医科大学生理学教研室,贵州遵义563099

出　　处：《遵义医科大学学报》2023年第6期546-552,共7页Journal of Zunyi Medical University

基　　金：国家自然科学基金(NO:81960161);黔科合平台人才[NO:(2017)5733-018]。

摘　　要：目的观察HCN通道对培养的大鼠脊髓背角神经元嘌呤能P2X受体激活诱发的[Ca^(2+)]i的调节作用。方法培养乳鼠脊髓背角神经元,分七组:对照组;ATP组(100μmol/L);无钙液+ATP组(无钙液预先孵育20 min,再加入ATP);PPADS+ATP组(50μmol/L PPADS预先孵育10 min,再加入ATP);ZD7288+ATP组(1、10、100、1000μmol/LZD7288预先孵育10 min,再加ATP);8-Br-cAMP+ATP组(100μmol/L 8-Br-cAMP孵育10 min后加ATP);ZD7288+8-Br-cAMP+ATP组(先加100μmol/L ZD7288孵育10 min,再加100μmol/L 8-Br-cAMP孵育10 min,最后加ATP)。采用激光共聚焦显微镜检测神经元[Ca^(2+)]i的变化。结果ATP(100μmol/L)可显著增加背角神经元的[Ca^(2+)]i,P2X受体拮抗剂PPADS可阻断该作用(P<0.05);HCN通道拮抗剂ZD7288(10~1000μmol/L)可剂量依赖性地抑制ATP(100μmol/L)诱发的[Ca^(2+)]i升高;8-Br-cAMP(膜透性cAMP类似物,一种PKA激活剂,100μmol/L)可显著增强ATP诱发脊髓背角神经元[Ca^(2+)]i升高的效应,而ZD7288(100μmol/L,预孵育10 min)可减弱8-Br-cAMP增强ATP诱发背角神经元[Ca^(2+)]i升高的效应(P<0.05),这说明阻断HCN通道活化可通过降低胞内cAMP-PKA活性而抑制脊髓背角神经元P2X受体功能。结论HCN通道可通过改变cAMP-PKA活性而调节脊髓背角神经元P2X受体功能。Objective To investigate the regulatory effect of HCN channel on[Ca^(2+)]i elevation induced by purinergic P2X receptor activation in cultured rat spinal dorsal horn neurons.Methods Spinal dorsal horn neurons of newborn SD rat were cultured and divided into 7 groups:Control;ATP(100μmol/L);Ca^(2+)-free solution(for 20 min)+ATP;PPADS(50μmol/L for 10 min)+ATP;ZD7288(1,10,100,1000μmol/L for 10 min)+ATP;8-Br-cAMP(100μmol/L for 10 min)+ATP;ZD7288(100μmol/L for 10 min)+8-Br-cAMP(100μmol/L for 10 min)+ATP.Changes of[Ca^(2+)]i in neurons were detected by laser scanning confocal microscopy.Results ATP(100μmol/L)significantly increased the[Ca^(2+)]i of spinal dorsal horn neurons,which was blocked by P2X receptor antagonist PPADS(P<0.05).HCN channel antagonists ZD7288(10-1000μmol/L)inhibited ATP-induced[Ca^(2+)]i increase with a dose-dependent manner.8-Br-cAMP(membrane permeability cAMP analogue,also known as an activator of PKA,100μmol/L)significantly enhance the[Ca^(2+)]i elevation induced by ATP in spinal dorsal horn neurons,while ZD7288(100μmol/L,preincubation for 10 min)attenuated the 8-Br-cAMP enhanced ATP-induced[Ca^(2+)]i elevation(P<0.05).These results suggest that blocking HCN channel activation may inhibit P2X receptor function in spinal dorsal horn neurons by reducing intracellular cAMP-PKA activity.Conclusion HCN channel may regulate P2X receptor function in spinal dorsal horn neurons by modifying intracellular cAMP-PKA activity.

关 键 词：HCN通道 脊髓 神经元 P2X受体 

分 类 号：R338.8[医药卫生—人体生理学]