KISS1 and polycystic ovary syndrome: Whilst these data show largely similar effects to those seen in normal women, the differences in both the effects of NK3R antagonism and response to kisspeptin-10 may be attributable to the precise level of sex-steroid feedback, and do not indicate major differences in the neuroendocrine regulation of LH secretion in PCOS at the level of the KNDy neurone.