Chunk #46 — RESULTS — Hyperexcitability is reversed by chronic Li treatment of LR DG-like neurons but not of NR neurons, and Li treatment reduces cell capacitance in both LR and NR neurons
Surprisingly, Li treatment caused a significant reduction in the cell capacitance for both LR (−23%, P = 0.0022, Figure 6h) and NR (−30%, P = 0.0016, Figure 6p) neurons. The cell capacitance is proportional to the total area of the membrane, and a reduction may be related to a smaller cell body or fewer branched dendrites/axons. To understand how cell capacitance correlates with excitability, we plotted the total number of spikes vs the capacitance (Supplementary Figures 3o–q, for control, LR and NR, respectively). The Pearson’s correlation for control cells and LR cells was 0.44, whereas for NR cells the correlation was 0.26. Li had the effect of slowing the cell growth and subsequent size, suggesting another explanation of how NR neurons are less affected by Li treatment. While smaller LR neurons are less excitable, smaller NR neurons can be hyperexcitable, as shown by the reduced correlation between cell capacitance and excitability in NR neurons.
