Fig. S4.
Electrophysiological and immunohistochemical identification of 5-HT neurons in the DRN. (A) Schematic of whole-cell recording from a DRN 5-HT neuron. (B, 1) Whole-cell voltage-clamp recording from a 5-HT neuron and change in holding current in response to bath application of the 5HT1A receptor agonist 5-CT (100 nM). (B, 2) Whole-cell current-clamp recording from a DRN 5-HT neuron. The neuron was brought to spike consistently with the current injection. A 5-CT bath application induced a characteristic 5HT1A-mediated hyperpolarization and inhibition of spiking. (C) Characteristic firing pattern of DRN 5-HT neurons. (D, 1) Post hoc immunolabeling for TPH2 in a 5-HT neuron filled with biocytin during whole-cell recordings. (D, 2) Two-photon image of Alexa-594–filled 5-HT neuron in the DRN.