Fig. 9.

Localization of mGluR3 in postsynaptic compartments in dendritic spines and shafts in ERC layer II. (A–E) mGluR3 were expressed on dendritic spines, both in perisynaptic and extrasynaptic locations adjacent to the asymmetric synapse (A, B, C, E) and within the synapse per se (D1–D2), often near the SER spine apparatus (pseudocolored pink). Higher magnification image of mGluR3 in D2 revealed precise immunolabeling directly in association with the synaptic junction. The dendritic spine was visualized emanating from a dendritic shaft in D1. (F) Within dendritic shafts, mGluR3 channels were observed on the plasma membrane near axodendritic glutamatergic-like excitatory synapses; synapses are between black arrows. Color-coded arrowheads point to mGluR3 (yellow) immunoreactivity. Profiles are pseudocolored for clarity. Ax, axon; Sp, dendritic spine; Den, dendrite; Mit, mitochondria. Scale bars, 200 nm.