PRESENCE OF TRANSFORMING-GROWTH-FACTOR-ALPHA AND EPIDERMAL GROWTH-FACTOR IN HUMAN OVARIAN TISSUE AND FOLLICULAR-FLUID

Intra-ovarian regulation of follicular maturation is modulated by vari ous factors. Among these, growth factors are important local actors. W e examined the immunohistochemical localization of transforming growth factor alpha (TGF-alpha), epidermal growth factor (EGF) and epidermal growth factor receptor (EGF-R) in 18 human ovaries. The concentration of TGF-alpha and EGF in follicular fluid was measured by ELISA, TGF-a lpha was detected in oocytes of primordial and early preantral follicl es, Furthermore, staining was observed in granulosa cells of preantral follicles and in theca cells of preantral, antral and preovulatory fo llicles, EGF showed a similar distribution as TGF-alpha. Atretic folli cles were strongly positive for TGF-alpha and EGF. In the corpus luteu m, theca lutein cells were strongly positive for TGF-alpha and EGF. Im munoreactivity for EGF-R was observed only in the granulosa cells of a ntral follicles. Follicular fluids from patients undergoing in-vitro f ertilization (IVF) were examined for their content of TGF-alpha and EG F. TGF-alpha was detected in 37% of the samples. The concentration ran ged from 43 pg/ml to 602 pg/ml. EGF was not detected in any of the fol licular fluids tested. These observations support the participation of EGF/TGF-alpha in follicular maturation. Furthermore, the presence of TGF-alpha in follicular fluid and the simultaneous absence of EGF sugg ests that TGF-alpha plays a more pronounced role than EGF in oocyte ma turation during late follicular phase.