Animal models of polycystic ovary syndrome: A review of hormone‐induced rodent models focused on hypothalamus‐pituitary‐ovary axis and neuropeptides

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common endocrine disorder among women of reproductive age and a major cause of infertility; however, the pathophysiology of this syndrome is not fully understood. This can be addressed using appropriate animal models of PCOS. In this review, we describe rodent models of hormone‐induced PCOS that focus on the perturbation of the hypothalamic‐pituitary‐ovary (HPO) axis and abnormalities in neuropeptide levels. METHODS: Comparison of rodent models of hormone‐induced PCOS. MAIN FINDINGS: The main method used to generate rodent models of PCOS was subcutaneous injection or implantation of androgens, estrogens, antiprogestin, or aromatase inhibitor. Androgens were administered to animals pre‐ or postnatally. Alterations in the levels of kisspeptin and related molecules have been reported in these models. CONCLUSION: The most appropriate model for the research objective and hypothesis should be established. Dysregulation of the HPO axis followed by elevated serum luteinizing hormone levels, hyperandrogenism, and metabolic disturbance contribute to the complex etiology of PCOS. These phenotypes of the human disease are recapitulated in hormone‐induced PCOS models. Thus, evidence from animal models can help to clarify the pathophysiology of PCOS.