Deep brain stimulation on the external segment of the globus pallidus improves the electrical activity of internal segment of globus pallidus in a rat model of Parkinson's disease

Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by the progressive degen-eration of neurons in the substantia nigra pars compacta. Deep brain stimulation (DBS) is an effective treatment for PD cardinal motor symptoms. DBS of GPe has been recognized as an effective treatment option for motor symptoms of PD, but the mechanism is still essentially unknown. To investigate the impact of DBS in the external segment of globus pallidus (GPe) on the pathway of the basal ganglia (BG), we recorded the electrical activities of single neurons and local field potential (LFP) of the internal segment of globus pallidus (GPi). The results showed that the firing rate of GPi neurons in the 6-OHDA lesioned rats returned to the normal level after GPe-DBS for two weeks. Moreover, the CV value of GPi neurons is significantly lower than that in the PD group. The different frequency bands of GPi LFP in PD rats have improved correspondingly. These findings indicate that the improvement of the electrical activity of GPi by GPe-DBS in PD rats may be an important electrophysiological mechanism for treating PD.