Objective:To explore the possible underlying mechanism by investigating the effect of electroacupuncture(EA)treatment on the primary motor cortex and striatum in a unilateral 6-hydroxydopamine(6-0HDA)induced rat Parkinson's disease(PD)model.Methods:Male Sprague-Dawley rats were randomly divided into sham group(n=16),model group(n=14),and EA group(n=14).EA stimulation at Dazhui(GV 14)and Baihui(GV20)was applied to PD rats in the EA group for 4 weeks.Behavioral tests were conducted to evaluate the effectiveness of EA treatment.Metabolites were detected by 7.0 T proton nuclear magnetic resonance.Results:Following 4 weeks of EA treatment in PD model rats,the abnormal behavioral impairment induced by 6-0HDA was alleviated.In monitoring changes in metabolic activity,ratios of myoinositol/creatine(Cr)and N-acetyl aspartate(NAA)/Cr in the primary motor cortex were significantly lower at the injected side than the non-injected side in PD rats(P=0.024 and 0.020).The ratios of glutamate+glutamine(Glx)/Cr and NAA/Cr in the striatum were higher and lower,respectively,at the injected side than the non-injected side(P=0.046 and 0.008).EA treatment restored the balance of metabolic activity in the primary motor cortex and striatum.In addition,the taurine/Cr ratio and GIx/Cr ratio were elevated in the striatum of PD model rats compared to sham-lesioned rats(P=0.026 and 0.000).EA treatment alleviated the excessive glutamatergic transmission by down-regulating the striatal Glx/Cr ratio(P=0.001).The Glx/Cr ratio was negatively correlated with floor plane spontaneous locomotion in PD rats(P=0.027 and P=0.0007).Conclusions:EA treatment is able to normalize the metabolic balance in the primary motor cortex and striatum of PD rats,which may contribute to its therapeutic effect on motor deficits.The striatal GIx/Cr ratio may serve as a potential indicator of PD and a therapeutic target of EA treatment.
