Angiopoietin 1 and angiopoietin 2 in follicular fluid of women undergoing a long protocol

Objective: To determine the concentrations of angiopoietin 1 (ANGPT1) and ANGPT2 in individual human pre-ovulatory follicles in relation to their diameter or volume to clarify the role of these molecules in folliculogenesis. Design: Prospective study. Setting: Research laboratory at Kansai Medical University, Osaka, Japan. Patient(s): Twenty-three women undergoing IVF. Intervention(s): On the day of oocyte retrieval, serum samples and follicular fluid (FF) from individual follicles were collected. We analyzed 348 follicles. Main Outcome Measure(s): ANGPT1 and ANGPT2 concentrations in FF and serum and oocyte recovery rates. Result(s): On average, ANGPT1 concentrations in FF were 150 times lower than those in serum, whereas ANGPT2 concentrations in FF were 8 times higher than those in serum. The concentrations of ANGPT1 in follicles with a diameter <= 17 mm were significantly higher than those in follicles with a diameter >= 18 mm. On the other hand, the concentrations of ANGPT2 in follicles with a diameter <= 17 mm were significantly lower than those in follicles with a diameter >= 18 mm. The ANGPT2/ANGPT1 ratio increased with enlargement of follicular diameter. ANGPT1 concentrations in FF decreased with follicular volume. ANGPT2 concentrations and the ANGPT2/ANGPT1 ratio in FF rose with follicular volume. The ANGPT2/ANGPT1 ratio in FF from the oocyte recovery group was significantly higher than that from the nonrecovery group. Conclusion(s): Our data suggested that the change in ANGPT1 and ANGPT2 levels may be associated with follicular growth and angiogenesis during the preovulatory period. (Fertil Steril (R) 2011; 96: 1378-83. (C) 2011 by American Society for Reproductive Medicine.)