Objectives: To investigate the relationship between elevated luteinizing hormone (LH), hyperinsulinemia and neuropeptides in patients with polycystic ovarian syndrome (PCOS).
Methods: An oral glucose (100g) tolerance test (OGTT) was performed in 15 normally menstruating women (control) and 30 PCOS women with LH/follicle stimulating hormone (FSH) ratio greater than 3 (group 1) and 25 PCOS subjects with the ratio < 3 (group 2). The responses of insulin, somatostatin (SS), beta-endorphin (beta-EP) and dynorphin A (Dyn A) during OGTT were measured by RIA.
Results: In basal state, significant negative correlations were found between LH and SS (r = -0.51, P < 0.05) in group 1 and between LH and beta-EP (r = -0.49, P < 0.05) in group 2. During OGTT, PCOS women had a greater beta-EP and Dyn A responses in group 1 and an impaired SS response in group 2 as compared with the control.
Conclusion: These data suggested lower endogenous SS, higher beta-EP and Dyn A may lead to elevation of LH and insulin secretions in patients with PCOS.