Evidence for the presence of hepatocyte growth factor expression in human ovarian follicles

The presence of hepatocyte growth factor (HGF) in follicular fluid (FF) relative to concentrations of sex steroid hormones and human chorionic gonadotrophin (HCG) was investigated. A total of 69 FF samples were obtained during oocyte retrieval for in-vitro fertilization (IVF) from 11 patients with no apparent endocrine disorders. The concentrations of HGF, oestradiol, progesterone, HCG and testosterone in FF samples were measured by enzyme-linked immunosorbent assay. Transcription of HGF and its receptor, c-met, was detected by reverse transcription-polymerase chain reaction (RT-PCR). Human FF samples contained approximately 90-fold higher amounts of HGF (24.2 +/- 1.2 ng/ml), compared with those of serum (0. 28 +/- 0.04 ng/ml). Concentrations of HGF in FF were positively correlated with those of progesterone (r = 0.649, P < 0.0001) and HCG (r = 0.264, P = 0.026) concentrations in FF. However, HGF concentrations were not significantly correlated with oestradiol and testosterone. HGF in FF was detected by Western blotting, as a single 90 kDa band, corresponding to a single chain form. Additionally, mRNA for both HGF and its receptor were detected in a crude granulosa cell preparation from the pre-ovulatory follicles. These findings suggest that HGF is produced locally in human ovarian follicles and may have a physiological role as an autocrine/paracrine factor.