Fig. 1

Prolonged alterations of hippocampal network activity induce homeostatic synaptic plasticity and regulate STEP₆₁ level. a–d Whole-cell patch clamp recording of miniature excitatory postsynaptic currents (mEPSCs) from rat dissociated hippocampal neurons cultured in high density that were treated for 48 h with vehicle control (CTL, 0.1 % H₂O), TTX (1 μM), or BC (20 μM) at 12–14 days in vitro. a Representative traces of mEPSCs. b Normalized cumulative fraction of the mEPSC amplitudes. c–d Summary plots of average mEPSC amplitudes (c) and frequencies (d) for CTL (n = 19), TTX (n = 20), or BC (n = 16). TTX treatment for 48 h induced synaptic scaling whereas 48 h BC treatment had no effect. e Microarray (n = 4) and QPCR (n = 5) analyses revealed that 48 h application of TTX but not BC reduced the expression of PTPN5, which encodes STEP. f–g Immunoblot analysis of STEP₆₁ following 48 h administration of CTL, TTX (F), BC (g) (n = 9 per treatment). Data shown represent the mean ± SEM (*p < 0.05; **p < 0.01)