Origin version 8

We performed whole-cell patch-clamp recordings with borosilicate glass micropipettes (Harvard Apparatus 30-0057) heat polished to obtain direct current resistances of ∼4–6 MΩ. Micropipettes were filled with an internal solution containing in mM: 115 KH₂PO₄, 2 MgCl₂, 10 HEPES, 0.5 EGTA, 0.2 Na₂ATP, and 0.2 Na₃GTP. The recordings were made with a microelectrode amplifier with bridge and voltage clamp modes of operation (BVC-700A, Dagan Co, Minneapolis, MN, USA). In some cases, conventional characterization of neurons was made in voltage and current clamp configurations. Access resistances were continuously monitored to be less than 20 MΩ, experiments with changes over 20 % were interrupted and terminated. Software designed in LabVIEW environment (National Instruments) was used for data acquisition and we performed analysis with Origin (version 8.6, Microcal, Northampton, MA, USA).

Neurons (15–25 DIV) were recorded with borosilicate glass micropipettes heat polished to obtain direct current resistances of 4–6 MΩ. Micropipettes were filled with an internal solution containing in mM: 115 KH₂PO₄, 2 MgCl₂, 10 HEPES, 0.5 EGTA, 0.2 Na₂ATP, and 0.2 Na₃GTP. A microelectrode amplifier with bridge and voltage clamp modes of operation (Axoclamp 700B Molecular Probes, USA) was used. Conventional characterization of neurons was performed in voltage and current clamp configurations. Access resistances were continuously monitored and recordings with changes in resistance greater than 20% were aborted. pClamp software was used for data acquisition and analyses were performed using Origin (version 8.6, Microcal, Northampton, MA). To elicit synaptic potentials, channel rhodopsin was excited using an LED light-source providing a maximum of 15 mW power (OptoLED, Cairn Research Co., U.K.). Theta burst stimulation consisted of 6 trains of 5 pulses at 4 Hz delivered at 10 s intervals.