Adrenal Function in Normal Women and Women with the Poly cystic Ovary Syndrome*

Abstract

The role of the adrenal gland in the polycystic ovary syndrome (PCO) was reassessed. A series of C₁₉ and C₂₁ steroids and pituitary hormones was investigated by measurements of serum cortisol, dehydroepiandrosterone (DHEA), an-drostenediol (Adiol), androstenedione (A), testosterone (T), pregnenolone (Pe), 17-hydroxypregnenolone (17Pe), progester-one (Po), 17-hydroxyprogesterone (17Po), DHEA sulphate, sex hormone-binding globulin (SHBG), LH, FSH, and PRL in nine normal women in the early follicular phase of the menstrual cycle and nine women with PCO. Fluctuations of C₁₉ and their C₂₁ precursors were determined during the 24-h endogenous ACTH swings. The responses to dexamethasone suppression and to subsequent stimulation with two small pulses (200 ng/1.5 m²) of ACTH (to assess adrenal sensitivity) and an infusion (20 μg/2 h) of ACTH (to assess adrenal capacity) were analyzed. Significantly elevated basal levels of A, T, 17Po, and LH were found in the PCO group. In the normal subjects, a circadian rhythm significantly synchronized with the cortisol rhythm was found for all four C₁₉ steroids (DHEA, Adiol, A, and T) and their C₂₁ precursors (Pe, 17Pe, and 17Po), with the exception of Po. In PCO patients, there was a blunting of the midnight nadir for A, T, and 17Po. A significant and quantitatively similar suppression i n response to dexamethasone was found for all steroid hormones, except Po, in both groups of subjects. The responses to the pulses of ACTH were also similar in the two groups, but in response to the infusion of ACTH there was a significantly greater increase in circulating levels of DHEA, 17Pe, Po, and 17Po and a significantly smaller increase in Adiol, A, and T in the PCO group compared with the normal group. Cortisol and Pe responses were similar in the two groups. The selective hyperresponses of adrenal steroids in PCO patients, disclosed only under sustained adrenal stimulation, are compatible with a secondary effect of increased androgen production rather than a classical enzyme block.