DETECTION OF MESSENGER-RNA AND IMMUNOREACTIVE PROTEINS FOR ACIDIC ANDBASIC FIBROBLAST GROWTH-FACTOR AND EXPRESSION OF THE FIBROBLAST GROWTH-FACTOR RECEPTORS IN THE BOVINE OVIDUCT

The heparin-binding acidic and basic fibroblast growth factors (aFGF, bFGF) and their receptors in the bovine oviduct are described. By mean s of western blot analysis one 18 kDa aFGF and two bFGF proteins (16 a nd 18 kDa, respectively) were detected in oviductal flushings. Differe nt concentrations of these two growth factors could be measured in ovi ductal flushings during the oestrous cycle: concentrations of aFGF pro tein were significantly higher at ovulation (mean +/- SEM; 5.3 +/- 0.5 ng ml(-1)) than during the luteal phase (3.0 +/- 0.3 ng ml(-1)); conc entrations of bFGF were higher at the preovulatory stage (3.5 +/- 0.7 ng ml(-1)) than at the post-ovulatory stage (1.3 +/- 0.15 ng ml(-1)). Immunohistochemical studies using a/bFGF-specific antibodies indicated that these growth factors were localized mainly in oviduct epithelial cells. The sequence of the bovine FGF receptor (FGFR) was partly dete rmined. Quantification of mRNAs by an RNase-protection assay (RPA) sho wed that expression of aFGF and bFGF was different during the oestrous cycle, indicating that the regulation of aFGF is separate from that o f bFGF. Only mRNA encoding bFGF and FGFR could be detected in cumulus- oocyte complexes by reverse transcription PCR. In summary, the compone nts of the FGF system were found in the bovine oviduct suggesting an a utocrine or paracrine regulation involving oviduct cells and cumulus-o ocyte complexes.