| Parkinson’s disease (PD) is a kind of motility disorder commonly in Middle and elderlypopulation, seriously threaten human health due to its high incidence and morbidity. How toremedy PD and improve patients’motor function and the quality of life becomes the focus ofattention.This study used rats as research objects, using 6-hydroxydopamine (6-OHDA) to producePD model. Behavioral differences between PD rats and the control were tested by usinghomemade ladder and treadmill models. The experimental results were verified by injecting APOand observing the histological changes.After the behavioral tests, synchronously recorded the changes of Local Field Potential(LFP )signal from the control and PD rats’Primary Motor Cortex ( M1) and Internal segment ofGlobus Pallidus (IGP) or External segment of Globus Pallidus (IGP) when they were in differentbehavior states, utilizing homemade metal microelectrodes and multi-channel physiologicalsignal acquisition and processing device. Time domain, frequency domain and time-frequencydomain analysis were managed through Matlab. The study was to uncover the changes firingpattern of M1, IGP and EGP caused by PD pathology and the correlation between M1 and IGP orEGP.Behavioral tests showed that: in the ladder experiment, compared with the sham group andthe normal group, the walking speed of PD rats was compared decreased, the walking time wasremarkably prolonged（P＜0.05）, and the walking error rate was also increased notably（P＜0.01）. In the treadmill experiment, the creeping time shortened remarkably, and the falling timein certain period also increased notably（P＜0.01）. Histological observation, the DA neurons ofthe PD rats’Substantia Nigra Pars Compacta (SNc) which injected drugs was decreasedobviously, the integrality of nucleus and cytoplasm were damaged, and the hyperplasia of glialcell hyperplasiaed obviously. Signal analysis results showed that: according to the change characteristics of waveformsignals of LFPs of M1, IGP and EGP, pointed the crawling process for three periods: the crawlprophase, the transitional period and the crawling period. No matter PD rats or the normal group,the LFP signal change which in the crawling period is the most obvious. In PD rats, 25-100 Hzfrequency band signal activity increased significantly in the LFP signal of M1 and EGP. At thesame time, 25-40Hz frequency band signal activity also increased in the LFP signal of IGP. Theresults showed that: the electric activity of M1, EGP and IGP were enhanced in PD pathologystate. And M1, EGP electrical activity increased significantly, the increase of IGP was notremarkable as M1 and EGP. And the activities of the signal were given priority to 0-12 Hzfrequency band in the normal group.The Cross-Correlation analysis showed that: the correlation coefficient of M1 with EGPwas bigger than M1 with IGP, so the signal correlation of M1 with EGP was higher than M1 withIGP. The LFP signal of IGP lagged behind M1, and the LFP signal of EGP also occurred behindM1 in resting stage, but it happened before M1 in crawling period. In PD state, the correlationcoefficient of M1 with EGP increased close to 1, showed that the discharge synchronicities wasconsistently. The correlation coefficient of M1 with IGP also increased, showed that thedischarge synchronicities was also increased, but only appeared in crawling period. At the sametime, the time difference of firing activity between M1 with EGP and M1 with IGP occurredreduction in different degree. And showed that the discharge synchronicities increased indifferent degree.Conclusion: homemade behavior model received good effect in the back of the records andanalysis the discharge characteristics of cortex and Globus Pallidus, and the correlation with thecorresponding motion state. PD lesions caused the electrical activity of the M1 and EGPenhanced significantly, and the IGP electrical activity also increased, but not as significant as M1and EGP. And caused the synchronicity of electrical activity enhanced between M1 with EGP orIGP. Reduced the signal transmission time from M1 to IGP and from EGP to M1. |
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