Figure 2. MPD is largely preserved during activation of GABA_BRs and mAChRs.

A, train of presynaptic action potentials evoked by brief current pulses (top trace) and corresponding average IPSCs (bottom traces) in control, in the presence of 10 μm baclofen and after wash. Average IPSCs were obtained from 50 individual sweeps. B, mean ratio of IPSC_n/IPSC₁, plotted against the number within the train (n). ○, data in control; •, data in 10 μm baclofen; □, data after wash (all normalized to IPSC₁ in control). ▪, data in 10 μm baclofen (normalized to IPSC₁ in baclofen). Curves represent exponential fits to control data points (continuous; τ= 28 ms, offset 0.31) and data points in baclofen (dashed; τ= 41 ms, offset 0.50). Data from 7 (control), 7 (10 μm baclofen) and 4 pairs (wash). C and D, data similar to those shown in A and B, with 2 μm carbachol instead of baclofen. Curves represent exponential fits to control data points (continuous; τ= 34 ms, offset 0.38) and data points in carbachol (dashed; τ= 37 ms, offset 0.50). Data from 8 pairs. The stimulation frequency during the train was 50 Hz in all experiments.