帕金森病与肌张力障碍患者内苍白球放电活动的特点

Differential neuronal firing in globus pallidus internus of patients with Parkinson＇s disease and dystonia

目的探讨帕金森病和肌张力障碍患者内苍白球神经元电活动特点，揭示其病理生理基础。方法时间对象为13例原发性帕金森病患者和8例原发性肌张力障碍患者，在接受立体定向手术的同时应用微电极记录技术采集内苍白球神经元电活动和肢体EMG。应用单细胞、峰间隔（ISI）、ISI变异系数（CV）等方法探讨神经元放电频率和模式。结果在帕金森病患者内苍白球中共甄别出108个神经元，除19．4％为与震颤相关的神经元放电活动外，55．6％为紧张性放电活动，平均放电频率为（103．7±25．5）Hz；25．0％为不规则放电活动，平均放电频率为（63．4±16．1）Hz。在肌张力障碍患者内苍白球中甄别出45个神经元，37．8％为紧张性放电活动，平均放电频率为（50．2±19．1）Hz。62．2％为不规则放电活动，平均放电频率为（28．5±10．5）Hz。方差分析显示两组患者内苍白球紧张性、不规则性神经元平均放电频率之间差异有统计学意义（P〈0．001），帕金森病患者内苍白球放电频率明显高于肌张力障碍患者（均P〈0．05）。结论内苍白球神经元放电频率的增加与帕金森病相关，而内苍白球神经元放电频率的减少与肌张力障碍相关，支持运动障碍病病理生理假说。

Objective To explore the neuronal activity in globus pallidus internus in patients with Parkinson＇s disease （PD） and dystonia. Methods Thirteen patients with Parkinson＇s disease and eight with dystonia undergoing stereotactic surgery of globus pallidus internus were studied. Microrecordiug in globus pallidus internus and electromyography on contralateral limbs to surgery were simultaneously performed. Single unit analysis, interspike intervals （ISI） and coefficient of variation of ISI were performed. ANOVA and Student t-test were employed to compare neuronal firing in globus pallidus internus between two patient groups. Results One hundred and eight neurons were identified from PD patients, including 19.4% tremor- related neuronal activity, 55.6% neurons with tonic firing and 25.0% neurons with irregular discharge. Further analysis revealed that neurons with tonic firing had a mean firing rate of（ 103.7 ±25.5 ） Hz; neurons with irregular discharge had a mean firing rate of （63.4± 16. 1 ） Hz. Forty-five neurons were identified from patients with dystonia, including 37.8% neurons with tonic firing and 62. 2% neurons with irregular discharge. Further analysis showed that neurons with tonic firing had a mean firing rate of（50. 2 ± 19. 1 ） Hz; neurons with irregular discharge had a mean firing rate of（28.5 ±10. 5） Hz. ANOVA showed that a significance of firing rate of tonic firing and irregular discharge in globus pallidus intemus was reached between two patient groups （P 〈 0. 001 ）. The mean firing rate of two patterns of neuronal activity in PD were significantly higher than those in dystonia （ Bonferroni test, both P 〈 0. 05 ）. Conclusion The data sopport the current view that an increased neuronal firing rate in globus pallidus internus is associated with PD whereas a decreased neuronal firing rate is associated with dystonia.