(a) Ectopic endometrial growths of mice treated with THC were smaller (left graph) and had less endometrial tissue (right graph) than those of mice receiving vehicle. Scale bar = 1 mm. (b) THC increased innervation in sham mice but prevented uterine hyperinnervation in endometriosis mice. Blue is DAPI and white is β-III tubulin. Scale bar = 100 μm. (c) As expected, 17-β estradiol levels were higher in mice in proestrus (left). Estrogen levels were similar in all experimental conditions (right). (d) There was a positive correlation between cyst diameter and plasma levels of 17-β estradiol (left, r = 0.450). Absence of correlation of estrogen levels with cyst endometrial area (middle, r = 0.263) and uterine innervation (right, r = 0.039). THC dose: 2 mg/kg/day. Error bars are mean ± SEM. Student t-test (a, left graph), Mann Whitney U (a, right graph), two-way ANOVA + Bonferroni (b), mixed model + Bonferroni (c, left); Two-way ANOVA (c, right) and Pearson correlation (d). *p<0.05, **p<0.01 vs sham. +p<0.05, ++p<0.01 vs vehicle. ^p<0.05, ^^p<0.01 vs proestrus. Endo, endometriosis; THC, Δ9-tetrahydrocannabinol.