CAJ | 학술논문

目的研究钙离子通道对大鼠黑质致密部(SNc)多巴胺能神经元暴发式放电模式产生和维持的机制.方法应用全细胞膜片钳的方法,施加N-甲基-D-天冬氨酸(NMDA)诱导神经元放电模式转变,观察并记录其相应放电模式的特点,记录并比较加入10 μmol/L NMDA前后全钙离子流和L-钙电流的变化情况,通过外液加入河豚毒素、维拉帕米、氯化镍后,分析暴发式放电产生和维持与L-钙通道激活之间的联系.结果加入NMDA后神经元放电模式转变为暴发式放电,该暴发式放电为平台电位及其上的动作电位构成;L-钙通道电流密度峰值在加入NMDA后明显增加,从(2.86±0.26) pA/pF(n =28)增加到(3.75 ±0.18) pA/pF(n =34),差异具有统计学意义(t=7.52,P=0.0028);采用L-钙阻断剂维拉帕米后暴发式放电中的平台电位几乎消失.结论 NMDA能够诱导SNc多巴胺能神经元转变为暴发式放电模式,而L-钙通道参与暴发式放电产生和维持的过程.
목적 연구개리자통도대대서흑질치밀부(SNc)다파알능신경원폭발식방전모식산생화유지적궤제.방법 응용전세포막편겸적방법,시가N-갑기-D-천동안산(NMDA)유도신경원방전모식전변,관찰병기록기상응방전모식적특점,기록병비교가입10 μmol/L NMDA전후전개리자류화L-개전류적변화정황,통과외액가입하돈독소、유랍파미、록화얼후,분석폭발식방전산생화유지여L-개통도격활지간적련계.결과 가입NMDA후신경원방전모식전변위폭발식방전,해폭발식방전위평태전위급기상적동작전위구성;L-개통도전류밀도봉치재가입NMDA후명현증가,종(2.86±0.26) pA/pF(n =28)증가도(3.75 ±0.18) pA/pF(n =34),차이구유통계학의의(t=7.52,P=0.0028);채용L-개조단제유랍파미후폭발식방전중적평태전위궤호소실.결론 NMDA능구유도SNc다파알능신경원전변위폭발식방전모식,이L-개통도삼여폭발식방전산생화유지적과정.
Objective To evaluate the role of calcium channel in the mechanism of the generation and maintenance of bursting firing of substantia nigra pars compacta (SNc) dopaminergic neurons in rats.Methods Using the patch clamp technique,we observed the firing pattern switching features after adding 10 μmol/L N-methyl-D-aspartic acid (NMDA),compared the changes of whole-calcium current and L-type calcium current with or without NMDA,and analyzed the correlation between the generation of burst firing and L-type calcium channel activation.Results After NMDA treatment,the firing pattern of SNc dopaminergic neurons changed to burst firing,which was compromised by a charastistic high plateau potential and series of action potential on it.The current density of L-type calcium current increased significantly after adding NMDA,which,from (2.86 ±0.26) pA/pF (n =28),significantly increased to (3.75 ± 0.18) pA/pF (n =34 ; t =7.52,P =0.002 8).The high plateau potential was almost abolished with the application of verapamil,a specific antagonist of L-type calcium channel.Consiusion NMDA could induce the firing pattern changed to burst firing in SNc dopaminergic neurons,while L-type calcium channel contributes to the process of generation and maintenance of burst firing.