Histomorphometric analysis of the endometrium in an ectopic model of endometriosis in mice.

Evaluate histomorphometry of ectopic and eutopic endometrial tissues in receptor mice. Eighteen female Balb/c were divided into 3 groups, 6 animals each: Control, no procedure; - Sham, animals that had the same procedures as GIII without receiving the ectopic endometrial implant. Instead, they received saline solution; - endometriosis model, animals had surgical intervention with an ectopic endometrial implant. GI and GIII mice were treated with 17β-estradiol, 100 µg/kg each. All animals were euthanized to collect uterine horns, which were fixed in 4% paraformaldehyde, embedded in paraffin, stained with Hematoxilin and Eosin and submitted to histomorphometric analyzes. Data underwent one-way ANOVA followed by Tukey's test. Local tissue growth, showing important lesions and adhesions, as well as dark cysts were noticed. In GIII group, there was an increase in number of blood vessels and glands (GIII ≥ GI and GIII  > .001). Thickening of the GIII endometrial epithelial was also evident (GIII ≥ GI and GIII.  > .001). We also noticed an increase in the number of eosinophils (GIII (GIII ≥ GI and GIII.  > .001). Easy to perform model, capable of reproducing morphological endometriosis characteristics. From our findings, there was an increase of endometrial thickness as well as an increase in the eosinophils population.