AR in FS autapses in human epileptic neocortical tissue.

<p>(A) Left, magnetic resonance imaging (MRI) of a patient's brain with glioma (red boxes) in the temporal lobe. This patient also showed severe epileptic seizures. Top, coronal plane; bottom, horizontal plane. Right, typical firing pattern of an FS neuron obtained from the periglioma tissue. Step current injection evoked a train of APs at ∼100 Hz without adaptation. Note the increase in spontaneous events after the AP train (inset). Pipette solution contained 75 mM Cl⁻. (B) Both single AP-evoked synchronous release (left) and AP burst-evoked PT-AR (right) in the FS neuron could be blocked by GABA_A receptor blocker picrotoxin (PTX, 50 µM). Single APs were evoked by brief (0.3∼0.5 ms in duration) step commands from −70 to 40 mV. (C) Example current traces showing the dependence of PT-AR duration and total number of events on the number and the frequency of APs. Inset, expansion for clarity. (D) Group data (two-way ANOVA analysis, <i>p</i><0.001 for both AP frequency and number).