Figure 9.
5-HT1A receptor distribution in the dendritic tree is dependent on the C-terminal segment. Primary cultures of rat hippocampal neurons (7 DIV) were transfected with the following plasmids: 5-HT1A-eGFP (A), 5-HT1A-eGFP plus CT1A (B), or 5-HT1AΔ407 (C). Immunofluorescence was performed with anti-GFP antibodies to enhance the GFP signal (A, B) or with anti-5-HT1A antibodies (C). D, Cumulated fluorescence profiles along the longest dendrite for each group (30 neurons analyzed). Note that cotransfection with an excess CT1A reduces the 5-HT1A-eGFP fluorescence in distal dendrites (B), whereas the complete absence of the C-terminal segment virtually abolishes the presence of the mutant receptor in dendrites (C). Scale bar, 50 μm.