Abstract
To investigate the relationship between elevated LH, hyperinsulinemia and neuropeptides in polycystic ovarian syndrome (PCOS), we measured the endogenous levels of insulin, somatostatin (SS), β-endorphin (β-EP) and dynorphin A (Dyn A) before and after a glucose load in three groups: group 1 (LH/ FSH ≥ 3, n = 30); group 2 (LH/FSH < 3, n = 25), and controls (n = 15). In the basal state, significantly negative correlations were found between LH and SS (r = -0.51, p < 0.05) in group 1 and between LH and β-EP (r = -0.49, p < 0.05) in group 2. After a glucose load, PCOS women had greater β-EP and Dyn A responses in group 1 and impaired SS response in group 2 as compared with the control. The data suggest endogenously lower SS, higher β-EP and Dyn A may contribute to the elevation of LH and insulin secretions in PCOS.