Fig. 3

TBOA elicits somatic amplification of dendritic inputs. a Illustration of stimulating and recording paradigm. Patch recordings were performed at the soma (I) or at the dendrites with different distances from the soma (II, 200 μm; III, 25 μm; IV, 10 μm). Low-frequency (0.1 Hz) basal stimulation was delivered at site II. b Sample traces showing the averaged EPSPs recorded at the soma or at the dendrites with different distances from soma. Sample EPSP traces are the average of 30 consecutive events recorded at the time marked by the numbers (1 or 2) from (c–f). c–f Graphs showing the time course and magnitude of the change in normalized EPSPs from a sample recording at the soma marked by I (c) or at dendrites located at different distances (marked by II, III, IV) from the soma (d–f). The TFB-TBOA (100 nM)-elicited potentiation in normalized EPSPs was only observed at the soma or at the dendrite located at site IV (10 μm distance) and was absent at site II (200 μm distance) or site III (25 μm). Notably, the potentiation magnitude in recordings at site IV (10 μm distance) was lower than that recorded at the soma. Left column, data from a sample recording. Right column, summary of results from all experiments. g Statistical histogram showing attenuation of TBOA-potentiated somatic EPSPs along the apical dendrite. Somatic EPSP potentiation was attenuated to the baseline level at apical dendrites within 25 μm from the soma. Data are means ± SEM. t test, *P < 0.05; **P < 0.01, ns, no significance