Figure 6.

Serotonin selectively depolarizes bipolar cells and regulates their survival

(A) Typical morphology of reconstructed bipolar cells (left) and basket cells (right).

(B) Example of voltage-clamp traces of bipolar cells (top) and basket cells (bottom) in response to serotonin puffs (gray bars). The insert is an example of a current clamp trace of a bipolar cell responding to serotonin puffs (gray bars).

(C) Quantification of cell charge of L2/3 bipolar cells (gray boxplot, n = 7 cells) and basket cells (green boxplot, n = 7 cells).

(D) Schematic of experimental design.

(E) Coronal sections through the primary somatosensory cortex of Vip^Cre/+;RCL^tdTomato mice at P21 injected with vehicle or fluoxetine treatment immunostained for Prox1 (cyan), tdTomato (red), and reelin (yellow, left) or calretinin (yellow, right). DAPI is shown for counterstaining (gray).

(F) Quantification of the density of all Htr3a+ interneurons (Prox1+), neurogliaform cells (Prox1+ and Reln+), bipolar cells (Prox1+, CR+, and VIP+), and basket cells (Prox1+, Reln−, and CR−) in control (gray boxplots, n = 4 mice) and fluoxetine-injected mice (green boxplots, n = 4 mice) at P21. Prox1+: two-tailed unpaired Student’s t test, p = 0.61. Prox1+ and Reln+: two-tailed unpaired Student’s t test, p = 0.98. Prox1+, mCherry+, and CR+: two-tailed unpaired Student’s t test: ^∗p = 0.01. Prox1+, CR−, and Reln−: two-tailed unpaired Student’s t test, p = 0.23.

Data in (C) and (F) are shown as boxplots (median, middle dash), lower and upper quartiles (box borders), and minimum and maximum (whiskers), and the adjacent data points indicate the charge of each cell (C) and average cell density in each animal (F). Scale bar, 100 μm. See also Figures S1 and S5.