Fig. 5: Aromatase regulation of synaptic inhibition and PV-IN PNNs is female-specific and independent of sex chromosomes.

A Aromatase protein (Arom, red) and parvalbumin (PV, green) expression in male mice dorsal CA1. Single-channel images are represented in gray scale. Scale bar: 20 μm. B Male mice received intraperitoneal (i.p.) injections of the aromatase blocker letrozole (LTZ) or vehicle (C) and processed for perineuronal nets (PNNs) analysis or electrophysiological recordings. C Group data for experiment in B (sIPSCs). Two-tailed Mann–Whitney tests, frequency U = 62, p = 0.41; amplitude, U = 58, p = 0.29; n = 13, 12 cells, 3 mice per group. D Group data for experiment in B (WFA staining). Two-way ANOVA, Treatment F(1, 13) = 1.897, p = 0.1916; n = 7, 8 mice. E XX or XY^Sry female mice were treated with LTZ and processed for PNNs analysis or electrophysiological recordings. F Group data for experiment in E (sIPSCs). Two-way ANOVA, Frequency Arom Block F(1, 58) = 12.68, p = 0.0007, Chromosomes F(1, 58) = 7.592, p = 0.0078, interaction F(1, 58) = 0.01428, p = 0.9053. Bonferroni’s comparisons, C vs Arom Block (XX), p = 0.0486, C vs Arom Block (XY^Sry−) p = 0.0157. Amplitude, Treatment F(1, 58) = 0.3, p = 0.58, Chromosomes F(1, 58) = 5.17, p = 0.03, interaction F(1, 58) = 5.17, p = 0.02. Bonferroni’s comparisons, C-Arom Block (XX), p = 0.4, C vs. Arom Block (XY^Sry−) p = 0.07; n = 12, 16, 17, 17 cells, 3 mice per group. G Group data for experiment in E (WFA staining). Two-way ANOVA, Female XX Arom Block F(1, 8) = 5.72, p = 0.0438, interaction F(17, 136) = 3.15, p = 0.0001; n = 5 mice. Female XY^Sry−, Arom Block F(1, 8) = 13.6, p = 0.006, interaction F(17, 136) = 3.29, p < 0.0001; n = 6, 4 mice. Graphs represent mean ± SEM. In C and F, circles represent individual values. *p < 0.05; ns, p > 0.05. Source data are provided as a Source Data file.