Impaired glutamatergic projection from the motor cortex to the subthalamic nucleus in 6-hydroxydopamine-lesioned hemi-parkinsonian rats.

Impaired glutamatergic projection from the motor cortex to the subthalamic nucleus in 6-hydroxydopamine-lesioned hemi-parkinsonian rats. Exp Neurol. 2017 Nov 07;: Authors: Wang YY, Wang Y, Jiang HF, Liu JH, Jia J, Wang K, Zhao F, Luo MH, Luo MM, Wang XM Abstract The glutamatergic projection from the motor cortex to the subthalamic nucleus (STN) constitutes the cortico-basal ganglia circuit and plays a critical role in the control of movement. Emerging evidence shows that the cortico-STN pathway is susceptible to dopamine depletion. Specifically in Parkinson's disease (PD), abnormal electrophysiological activities were observed in the motor cortex and STN, while the STN serves as a key target of deep brain stimulation for PD therapy. However, direct morphological changes in the cortico-STN connectivity in response to PD progress are poorly understood at present. In the present study, we used a trans-synaptic anterograde tracing method with herpes simplex virus-green fluorescent protein (HSV-GFP) to monitor the cortico-STN connectivity in a rat model of PD. We found that the connectivity from the primary motor cortex (M1) to the STN was impaired in parkinsonian rats as manifested by a marked decrease in trans-synaptic infection of HSV-GFP from M1 neurons to STN neurons in unilateral 6-hydroxydopamine (6-OHDA)-lesioned rats. Ultrastructural analysis with electron microscopy revealed that excitatory synapses in the STN were also impaired...
Source: Experimental Neurology - Category: Neurology Authors: Tags: Exp Neurol Source Type: research