INS and metabolic syndrome: This study indicates that treatment with letrozole results in PCOS with characteristics that are similar to those of human PCOS, including polycystic ovaries, elevated serum testosterone, weight gain, visceral adiposity, high levels of insulin as well as FBG in addition to insulin resistance, improper handling of ovarian lipids, atherogenic dyslipidemia, impaired Na + /K + ATPase activity and serum, cardiac, and ovarian oxidative stress.