Figure 6

Effect of neuromodulators on ACC excitatory synaptic transmission. A, A representative example of MED64 responses before (black) and after (red) 1S,3R–ACPD (200 μM) application. Stimulation (thunderbolt) was given in the deep layer (Ch. 37). Two channels (Ch. 19 from LII/III and Ch. 38 from LV/VI) are selected for further comparison. B, 1S,3R–ACPD (200 μM) was bath applied for 10 min (filled circle: Ch. 19; open circle: Ch. 38) in a single slice. Sample fEPSP recordings taken at the times indicated by the corresponding numbers are shown above the plot. Calibration: 300 μV, 20 ms. C, Averaged data of 5–7 activated channels in the superficial layer and deep layer in one slice. D, Pooled data of 7 mice (LII/III: 23.2 ± 6.5% of baseline, LV/VI: 42.7 ± 5.5% of baseline, n = 7 slices/7 mice). Bath application of 1S,3R-ACPD resulted in an acute inhibition that gradually recovered after washout. The superficial layer response exhibited a much more reduction than the deep layer. E, Four neuromodulators were sequentially applied. Significant differences could be found in the blocking effect of 1S,3R–ACPD and (R)-Baclofen between individual layers (n = 5 slices/5 mice). The horizontal bars indicate the period of drug application. Error bars represent SEM. F, Reduction index of the neuromodulators. 1S,3R–ACPD (LII/III: 74.3% ± 8.8%, LV/VI: 52.5 ± 2.3%, P = 0.003) and (R)-Baclofen (LII/III: 80.3 ± 2.8%, LV/VI: 51.1 ± 2.2%, P = 0.002) showed statistically significant difference between the layers. 2-CA (LII/III: 50.6 ± 5.5%, LV/VI: 47.1 ± 5.2%, P = 0.614) and Cch (LII/III: 61.5 ± 4.2%, LV/VI: 57.3 ± 2.5%, P = 0.538) exhibited no layer-related difference.