Figure 2.
Comparison of microglia densities in control male and females and following 10 days of ad libitum PLX5622 feeding. (A) The average microglia densities (number of cells/mm2) in different brains regions in control male and female rats, and rats fed for ten days ad libitum on PLX5622 chow. Controls (homogeneous columns, male in blue and female in magenta) showed small but significant (p = 1.28 × 10−6, 5.1 × 10−4 and 0.007 in the cortex, amygdala, and striatum, respectively) density differences between females and males within given brain regions. Large and significant differences (p ≤ 8.11 × 10−19 for females and p ≤ 6.21 × 10−9 for males, excluding the olfactory bulb) in the elimination of microglia from males and females were observed in all brain regions in response to PLX5622 chow (in diagonal stripes, Supplementary Table S2). Note that in the male olfactory bulb, the density of microglia was not altered by PLX5622 (p = 0.09). (B) Ratio values of averaged microglia densities in PLX5622-treated rats and control rats in different brain regions showed a significantly smaller effect of PLX5622 chow on male microglia densities than in females. CO—cortex, H—hippocampus, A—amygdala, S—striatum, CE—cerebellum, OB—olfactory bulb. Data are presented as mean number of cells/mm2 ± one standard deviation. ≥18 slices were prepared from the different brain regions of the different hemispheres (4 controls and 4 PLX5622-fed rats) of each sex. Significant differences were determined by a t-test for two samples assuming unequal variances. p value < 0.01 indicated a statistically significant difference. Underlined asterisks indicate statistical significance between males and females; asterisks indicate statistical significance between control and PLX5622-fed rats; vertical lines correspond to ± one standard deviation.