Figure 3.

Loss of FMRP alters synaptic plasticity and basal protein synthesis in the rat hippocampus. (A) Sample fEPSP traces from 5 min pre- and 55 min post-DHPG treatment are shown above average fEPSP plots for both WT and Fmr1 KO slices normalized to pre-DHPG baseline. (A) The magnitude of DHPG-induced LTD in WT and Fmr1 KO rats was not significantly different between genotypes. (B) While the persistent expression of mGluR-LTD did not require new protein synthesis in Fmr1 KO rats, mGluR-LTD was not maintained in WT rats in the presence of protein synthesis inhibitor cycloheximide. (C) Basal protein synthesis levels are excessive in dorsal hippocampal slices from Fmr1 KO rats compared with WT littermate controls. Calibration bars for A and B: 0.5 mV, 10 ms.