Autoradiographic study of mitochondrial complex I and glutamate receptors in the basal ganglia of rats after unilateral subthalamic lesion

A unilateral lesion of the subthalamic nucleus (STN) induced, in the short-term (≤ week), an ipsilateral decrease in [³H]dihydrorotenone binding to complex I in entopeduncular nucleus and substantia nigra pars reticulata (SNr). A slight reduction of [³H]MK-801 binding to N-methyl-d-aspartate (NMDA) receptors in the ipsilateral SNr was also found, whereas no changes in [³H]α-amino-3-hydroxy-5-methylisoxazole propionic acid binding were observed. The complex I decrease likely reflects a reduction in neuronal activity subsequent to the interruption of excitatory signaling from STN. The unexpected decrease in [³H]MK-801 binding in SNr may be related to presynaptic NMDA receptor modifications.