FIG. 7.
Adult (≥3-mo-old) S845A mutants also display a specific deficit in LTD. A: I-O curves generated by plotting FP slope against the amplitude of presynaptic fiber volley did not differ between S845A mutants (closed symbols) and WT littermates (open symbols). B: PPF ratios measured at various ISIs were not different between S845A mutants (closed symbols) and WT littermates (open symbols). C: LTP induced by delivering 4 trains of TBS was normal in the adult S845A mutants. WTs: open symbols; S845A mutants: closed symbols. Representative traces taken right before (thin line) and 2 h after LTP induction (thick line) are shown to the right. D: one train TBS (1×TBS) induced LTP was also normal in the adult S845A mutants. WTs: open symbols; S845A mutants: closed symbols. Superimposed representative traces taken before (thin line) and 2 h after LTD induction (thick line) are shown to the right. E: a 15-min train of PP-1 Hz (ISI = 50 ms) failed to induce LTD in hippocampal slices from the adult S845A mutants (closed symbols), while producing normal LTD in the WT littermates (open symbols). Representative traces taken right before (thin line) and 1 h after the onset of PP-1-Hz stimulation (thick line) are shown to the right.