Figure 4.

Synaptic and anatomical connectivity is unaltered in transgenic mice. A, Sample traces represent the average of 10 consecutive EPSCs evoked by cortical (CTX) and thalamic (Th) stimulation in MSNs of hMT1 mice. EPSCs were fully inhibited by a combination of NMDA and AMPA receptor antagonists (MK-801 30 μm, and CNQX 10 μm, respectively, gray traces). Bar plots show the latency values for both cortical (CTX) and thalamic (Th) stimulation. Short latency times (<1 ms) are consistent with a monosynaptic transmission. B, Summary graphs of PPR recorded from hWT and hMT1 MSNs plotted as a function of interstimulus interval for CTX (blue circles) and Th stimulation (red circles). C, D, Confocal images of striatal coronal sections from mice injected with a GFP-lentiviral vector. The infection area is represented in green, while the red immunostaining shows the VGluT2- and VGluT1-positive synaptic terminals. Projection of a series of optical sections showing isolated GFP-positive dendrites and spines (high magnification of the white boxes) contacted by VGluT2 and VGluT1-positive synaptic terminals. C₁, D₁, The histograms summarize the percentage of GFP area that colocalizes with VGluT2 and VGluT1 signals (normalized to the NT control values).