Recordings from dissociated hippocampal neurons: Electrophysiological recordings from outside-out patches excised from cultured hippocampal neurons (DIV 16–21) were performed at RT and a holding potential of −120 mV. Recordings were made within 24 hours after infection with an Axopatch 200B amplifier, low-pass filtered at 10 kHz, and sampled at 50–100 kHz. Pipettes made from quartzglass had resistances of 1–2 MΩ when filled with intracellular solution (in mM): 135 CsF, 33 CsOH, 2 MgCl2, 1 CaCl2 and 11 EGTA, pH 7.4. Extracellular solution applied to outside-out patches was composed as follows (in mM): 5.8 KCl, 144 NaCl, 0.9 MgCl2, 1.3 CaCl2, 0.7 NaH2PO4, 5.6 D-Glucose, and 10 HEPES, pH 7.4. Rapid application/removal of glutamate (10 mM dissolved in extracellular solution) was performed with a piezo-controlled fast application system with a double-barrel application pipette that enables solution exchanges within less than 100 µs (20–80%, measured by switching the open tip of the patch pipettes between normal and 10fold-diluted extracellular solution). Deactivation and desensitization of AMPARs were characterized by time constants derived from bi-exponential fits to the decay phase of the respective currents;
