Fig. 9.

Photomicrographs taken under dark-field epi-illumination (left) and histograms of frequency distribution of labeling (right) illustrating the effects of high-frequency stimulation of the subthalamic nucleus and of 6-hydroxydopamine lesion of nigral dopamine neurons on GAD67 mRNA expression in the ipsilateral substantia nigra pars reticulata. Sections were processed for in situhybridization with ³⁵S-radiolabeled GAD67 oligoprobe and for emulsion autoradiography. Illustrations concern the following conditions: control (A), stimulation alone (B), dopamine lesion alone (C), and dopamine lesion and subsequent stimulation (D). Scale bar, 20 μm.