Fig. 10.
Cell surface expression of NR1–1bmyc and NR1–4bmyc molecules in primary hippocampal neurons.A–C, A hippocampal neuron expressing NR1–1bmyc using recombinant adenoviruses. A, Cell surface staining detected by Cy3-conjugated secondary antibody. B, Total NR1–1bmyc staining detected by FITC-conjugated secondary antibody in the same dendrite. C, The superimposed image ofA and B. Diffuse intracellular staining and punctate cell surface staining of NR1–1bmyc were observed.D–F, A hippocampal neuron expressing NR1–4bmyc using recombinant adenoviruses. D, Cell surface staining.E, Total NR1–4bmyc staining. F, The superimposed image of D and E. The amount of NR1–4bmyc molecules on the cell surface is higher than that of NR1–1bmyc. G–L, Colocalization of cell surface NR1–4bmyc puncta and synaptophysin immunoreactivity. G,J, Cell surface staining using anti-myc antibody of distal (G) and proximal (J) dendrites. H,K, Anti-synaptophysin staining of the same dendrites.I, L, The superimposed image ofG and H, or J andK, respectively. NR1–4bmyc-positive puncta were in apposition to the presynaptic structure detected by anti-synaptophysin antibody (arrows). M, N, Fluorescence quantitation of hippocampal neurons. M, Fluorescence intensity (Cy3 fluorescence for cell surface NR1 and FITC fluorescence for total NR1) within a region of 50 μm2 was measured from 20 randomly selected neurons expressing myc-tagged NR1–1b or NR1–4b. The differences between NR1–1b and NR1–4b were significant for surface staining (t test; p < 0.005) but not for total staining (t test; p > 0.05).N, Fluorescence intensity ratio (cell surface NR1/total NR1) calculated from the data shown in M. Scale bar:A–F, 10 μm; G–L, 5 μm.