Figure 2.

Brain-wide search identifies the peptidergic neurons of the EW nucleus as selectively more active in pregnant female nest builders

(A) Strategy to map activity-dependent Fos expression in nest builders.

(B) Generation of statistical maps of Fos+ cell distribution using iDISCO+ clearing and light sheet microscopy.

(C) Design of the different experimental groups: five groups of two conditions were considered for the comparative study of nesting-induced regions. Two types of induced regions are further considered: nesting-induced regions found in all groups (greige) and regions specific to both pregnant and pseudopregnant mice (orange).

(D) Volcano plot of nesting-induced regions in pregnant females as fold change in Fos+ cells (nest builders over controls). Significant regions appearing in all nest builder groups are the MEPO, GRN, ZI, and CA1, and CA3 (tancolored). Significant regions present only in pregnant and pseudopregnant animals are the motor pontine formation and the EW nucleus.

(E) Coronal and sagittal views of the p value of the voxel maps of Fos+ cell densities at the level of the EW nucleus in virgin, pseudopregnant, and pregnant female mice, showing the presence of significant voxels of induced cells (green, arrows) in the EW nucleus only in pregnant and pseudopregnant animals. Student's t test (C and D). Scale bars are 500 μm. See also Figure S2.