Immunohistochemistry studies. Insula: the percentage of Gpr88 and Glra3 positive staining cells is higher and the staining is stronger in endometriosis mice compared with sham mice. The protein levels of Gpr88 and Glra3 in the insula of endometriosis mice increased 6.39- and 8.15-fold compared to sham mice (N = 20 per group). The percentage of Lct and Serpina3n positive staining cells is lower and the staining is lighter in endometriosis mice compare with sham mice. The protein levels of Lct and Serpina3n in insula of endometriosis mice decreased by 2.17- and 3.85-fold compared to sham mice (N = 10 per group), respectively (*P < 0.05; **P < 0.01; ***P < 0.005). Amygdala: the percentage of Lcn2 positive staining cells is higher and the staining is stronger, while the percentage of Nptx2 positive staining cells is lower and the staining is lighter in endometriosis mice compare with sham mice. The protein level of Lcn2 expression of endometriosis mice increased by 2.08- and Nptx2 decreased by 2.64-fold compared to sham mice (N = 20 per group). Scale: 50 μn for Lcn2 and Lct; 20 μn for Nptx2, Gpr88, Glra3, and Serpina3n.