However, we noted that the protein expression of RARRES2 was greater in the uterus of VD3-treated and PCOS rats, while in PCOS supplemented with VD3, we observed a lower expression of RARRES2 in the uterus vs. the control group (Figure 5B, p < 0.05). The gene discussed is RARRES2; the disease is polycystic ovary syndrome.