ALTERATIONS IN THE SENSITIVITY OF SERUM INSULIN-LIKE GROWTH-FACTOR-1 AND INSULIN-LIKE GROWTH-FACTOR BINDING PROTEIN-3 TO OCTREOTIDE IN POLYCYSTIC-OVARY-SYNDROME

Objective: To determine if the somatostatin analog, octreotide, affect s insulin and related peptides and, hence, androgen levels differently between polycystic ovary syndrome (PCOS) patients and controls. Desig n: Prospective controlled trial. Setting: Reproductive endocrinology c linic of our medical center. Patients: Eleven women with PCOS and six matched ovulatory controls. Interventions: Octreotide (100 mu g) was a dministered subcutaneously in the midfollicular phase, Serum was obtai ned before and at 60, 120, 180, and 240 minutes after octreotide. Main Outcome Measures: Fasting insulin, insulin-like growth factor 1 (IGF- 1), insulin-like growth factor binding protein-3 (IGFBP-3), T, androst enedione (A), and LH. Results: In PCOS, baseline levels of T, A, LH, a nd fasting insulin were significantly higher than in controls. Pretrea tment IGF-1 and IGFBP-3 levels were similar in PCOS and controls. Octr eotide reduced fasting insulin levels significantly but to a similar d egree in control and PCOS patients (77% and 90%, respectively). Both g roups also experienced a significant decrease in LH levels after octre otide administration, but no significant changes were demonstrated in serum T or A. However, serum IGF-1 suppression in PCOS was greater (63 % versus 8% in controls). Serum IGFBP-3 levels increased after octreot ide administration in both groups with a larger increase (40%) occurri ng in the PCOS patients.Conclusions: These data suggest that women wit h PCOS may be more sensitive to the effects of octreotide in decreasin g IGF-1 and increasing IGFBP-3. Although no significant changes could be demonstrated in ovarian androgens after a single dose, octreotide e ffectively reduced serum LH and insulin and, as such, may prove useful in treating some patients with PCOS.