Immuno-gold labeled glutamate particles in VGLUT1-labeled and -unlabeled terminals.

<p>(A) <b>Control</b>. Electron photomicrographs of VGLUT1-labeled (L-NT) and -unlabeled (UN-NT) nerve terminals making asymmetric synaptic contacts (arrow) onto dendritic spines (SP). The 10 nm gold particles within the nerve terminals (see arrowhead in the L-NT) indicate the location of an antibody against glutamate. The inserts show labeled details of a terminal containing VGLUT1-immunoreactive synaptic vesicles (above) and a terminal containing unlabeled synaptic vesicles (below). (B) <b>6-OHDA lesion</b>. L-NT and UN-NT both make asymmetric synaptic contacts (arrows) with SPs. The density of immuno-gold labeling within these terminals is similar to that of the control group (A). (C) <b>6-OHDA/STN lesion</b>: L-NT and UN-NT make asymmetric synaptic contacts (arrows) with SPs. The density of nerve terminal immuno-gold labeling is significantly reduced compared to the control (A) and 6OHDA (B) tissue. (D) <b>6-OHDA/STN stimulation</b>. Both L-NT and UN-NT make asymmetrical synaptic contacts (arrows) with SPs. The density of nerve terminal glutamate immuno-gold labeling is similar to that seen in the 6-OHDA/STN lesion group (C). (E) <b>6-OHDA/Sham-Stim</b>. The L-NT makes an asymmetric synaptic contact with the SP, and the UN-NT makes an asymmetric synaptic contact with a dendritic shaft (DEND). The density of nerve terminal glutamate immuno-gold labeling is greater than in the 6-OHDA/STN lesion (C) and 6-OHDA/STN stimulation (D) tissue. Calibration bar: 0.25 microns.