abstract
- OBJECTIVE: To correlate the temporal expression of transforming growth factor-alpha (TGF-alpha) and TGF-beta genes in granulosa cells (GC) and thecal cells from human follicles at various developmental stages and to determine their trophic effects on GCs. DESIGN: Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of extracted RNA from follicular GCs and theca cells. SETTING: Academic endocrinology laboratory. PATIENT(S): Premenopausal women undergoing total abdominal hysterectomy and bilateral salpingo-oophorectomy for nonovarian reasons. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Confirmation by the RT-PCR product for TGF-alpha and TGF-beta gene expression in GC and theca cells from human follicles at various developmental stages and (3)H-thymidine uptake in vitro to assess growth effects on GCs. RESULT(S): The RT-PCR product indicating the presence of TGF-alpha messenger RNA (mRNA) was found consistently in theca from healthy antral follicles. In theca from large follicles (>1.0 cm) the TGF-alpha PCR product was of reduced intensity. The TGF-alpha was absent or undetectable in granulosa cells from all follicle sizes. The PCR product for TGF-beta was generated by all GC and thecal cell RNAs from all follicle sizes examined. The TGF-alpha promoted and TGF-beta inhibited human GC growth. CONCLUSION(S): The presence of TGF-alpha gene expression in thecal cells coincides with periods of follicular growth. The expression of TGF-beta occurs in both cell types throughout antral follicle development. The TGF-alpha and TGF-beta have opposing trophic effects on GCs.