Inhibition of glutamate and acetylcholine release in behavioral improvement induced by electroacupuncture in parkinsonian rats

Prior evidence shows that acupuncture improves symptoms in both Parkinson's disease (PD) patients and animal models. We examined the effects of high-frequency (100 Hz) electroacupuncture (EA) on behavior in a rat PD model induced by medial forebrain bundle (MFB) transection. Neurotransmitters levels in the striatum were measured using in vivo microdialysis and high performance liquid chromatography (HPLC). High-frequency EA stimulation at Dazhui (GV14) and Baihui (GV20) acupoints decreased rotational behavior induced by apomorphine (APO) and improved motor coordination, protected axotomized dopaminergic neurons from degeneration in the substantia nigra (SN), it did not increase striatal dopamine (DA) levels. However, EA stimulation at acupoints significantly decreased the abnormally elevated glutamate (Glu) and acetylcholine (ACh) levels in the lesioned side of striatum. Moreover, the Glu levels correlated significantly with survival ratios of dopaminergic neurons in the SNc and rotational bahavior. These data suggested that behavioral alleviation with EA stimulation may be associated with modulation of neurotransmitters release, such as Glu and ACh in the striatum, rather than with DA restoration. (c) 2012 Elsevier Ireland Ltd. All rights reserved.