Figure 3.

Large-scale asynchrony does not result from polysynaptic transmission. A, Schematic of a microculture containing multiple neurons with polysynaptic connections (left) and an autaptic −astrocyte microculture (right). B, C, EPSCs evoked by stimulating a neuron on a multineuron +astrocyte microculture (left) or a solitary neuron on a −astrocyte microculture (right). Asterisks denote local peaks. All EPSCs are normalized to the peak, and control and drug EPSCs are superimposed. The unscaled traces are displayed in the insets. Calibrations: 10 ms, 2 nA. EPSCs were evoked in control solution (black) or in 2.5 μm CdCl₂ (orange; B). EPSCs in baseline solution (black) or in 50 nm NBQX (green; C). D, Common peak ratio (for a description of analysis, see Materials and Methods) was calculated for polysynaptic neurons (black bars) and −astrocyte neurons (red bars) in the CdCl₂ experiment (left; n = 8 and 11, respectively) and NBQX experiment (right; n = 6 and 8, respectively). *p < 0.05.