Study on PCOS rat models compared with the pathological features of PCOS patients

Objective To establish polycystic ovaries syndrome rat models induced by letrozole and dehydroepiandrosteron(DHEA), and compare them from the body mass index, ovarian morphology, ovarian volume and relative quality, serum sex hormone levels, impaired glucose tolerance, insulin levels with PCOS patients. Methods The study was performed in 60 rats aged 6 weeks and 60 rats aged 23 days and the two groups were administered with letrozole and DHEA respectively to induce PCOS rat model; 200 PCOS patients and 200 normal women of childbearing age were included. Body mass index(patients) or weight gain(rat), ovarian volume, hormone levels, impaired glucose tolerance and insulin levels were measured in each group. Results ①The body mass index and ovarian volume of PCOS patients were significantly higher than those of the control group(P<0.05); the incresaed weight of letrozole inducing rats was significantly more than the controls, also were ovarian volume and relative weight(P<0.05); while the ovarian volume of DHEA experimental rats was smaller than the controls(P<0.01). ②The five sex hormone levels of PCOS patients were all different with control group significantly (P<0.05); the levels of luteinizing hormone (LH) and testosterone(T) of letrozole experimental group were higher, while the levels of follicle stimulating hormone(FSH), estradiol(E2), progesterone(P) were lower(P<0.05); the levels of E2 and T of DHEA experimental group were higher, while the levels of FSH were lower(P<0.05); ③ The glucose of postprandial 1 h and 2 h with PCOS patient were both significantly higher than those of the control group; insulin release was different among the groups(P<0.05). FPG, 1 h, 2 h glucose and insulin release of rats in the two experimental groups were significantly higher than the control group (P<0.05), so was Homa-IR (P<0.01). Conclusions PCOS can lead to changes in endocrine and biochemical markers of patients, the two methods can both induce relative rat model; the feature of letrozole rats was more closer to the pathological features of PCOS. Key words: Polycystic ovaries syndrome; Rat model; Letrozole; Dehydroepiandrosteron