Action of mifepristone on the expression of insulin-like growth factor binding protein-1 mRNA and protein during the early luteal phase in the human oviduct

Objective: To investigate the effects of the antiprogestin mifepristone on the expression of insulin-like growth factor binding protein-1 (IGFBP-1) mRNA and protein during the early luteal phase in the human oviduct. Design: Prospective case-control study. Setting: University hospital. Patient(s): Fourteen healthy women with regular menstrual cycles who were admitted to the hospital for voluntary sterilization by the laparoscopic technique. Intervention(s): Treatment with 200 mg of mifepristone was administered on day LH+2. Fallopian tube samples were obtained on days LH+4 to LH+6. Main Outcome Measure(s): Expression of IGFBP-1 was identified using immunhistochemistry, and mRNA levels were determined with semiquantitative reverse transcriptase-polymerase chain reaction (RT-PCR). Result(s): Immunoreactivity for IGFBP-I was primarily localized to the cytoplasm of the oviductal epithelial cells. Messenger RNA for IGFBP-1 was identified in total RNA extracted from the same fallopian tube samples. There was a significant increase in the expression of IGFBP-1 immunostaining and mRNA after treatment with mifepristone. Conclusion(s): These data further illustrate the complex actions of mifepristone and support the view that changes in the oviductal environment after treatment with mifepristone may be detrimental to normal gamete transport and function and contribute to the contraceptive action of mifepristone. (C) 2003 by American Society for Reproductive Medicine.