Fig. 4.

DHPG-induced sIPSC synchronization is reduced in Fmr1 KO pyramidal neurons. A: simultaneous voltage-clamp recordings from 2 WT pyramidal RS neurons before (i) and after (ii) DHPG application, illustrating that sIPSC synchronization increases with DHPG (see magnified traces, bottom). B: cross-correlation analysis (bin width = 10 ms) revealed a strong central peak in DHPG, but not under control conditions. C: representative pyramidal neuron pair from an Fmr1 KO mouse (i). DHPG induced some sIPSC synchronization, but this was reduced compared with WT (ii). D: cross-correlogram for the cell pair in C is shown. E: DHPG increased cross-correlogram peak value in both WT and Fmr1 KO mice, but this effect was significantly greater in WT (n = 5 WT pairs and 5 Fmr1 KO pairs). *P < 0.05; **P < 0.01; ***P < 0.005. Calibrations: A and C (top traces): 50 pA, 2 s; A and C (bottom traces): 50 pA, 500 ms.