Abstract
The ability of platelet-derived growth factor (PDGF) preparations to potentiate FSH-mediated LH receptor induction in rat granulosa cell cultures was shown to be due to a component distinct from PDGF. Purification of heat-treated platelet lysate by carboxymethyl-Sephadex C-50 and Cibacron blue-Sepharose chromatography, followed by Bio-Gel P-60 chromatography, resulted in the separation of two activities: 1) a growth-promoting activity, P60-PDGF, defined on the basis of increased DNA synthesis in BALB/c-3T3 cells, and 2) a differentiation-promoting activity which enhanced FSH-dependent LH receptor induction in granulosa cells. On the basis of electrophoretic mobility on sodium dodecyl sulfate-polyacrylamide gels, inhibition of tritiated thymidine uptake by epithelial cells, and attenuation of LH/hCG receptor expression in the presence of antitransforming growth factor-beta (anti-TGF beta) immunoglobulin G, the differentiation-promoting component of the preparations appears to be TGF beta. The Bio-Gel fractions that contained TGF beta did not stimulate LH receptor induction of cAMP production in the absence of FSH. PDGF prepared free of TGF beta did not potentiate receptor induction. We conclude, therefore, that the differentiative effects of PDGF previously described in this system are due to TGF beta.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
