Inhibition of rat alpha-fetoprotein-estrogen interaction by adult rat ovarian extracts—role of unsaturated fatty acids

Thin layer chromatography with four different solvent systems enabeled us to show that ovarian extracts contained nonesterified unsaturated fatty acids able to compete with estradiol on the α-fetoprotein binding site. Gas chromatography demonstrated a high level of oleic and linoleic acids and the presence of arachidonic acid, a strong competitor of the rat α-fetoprotein-estrogen interaction. Arachidonic acid is a precursor of prostaglandins thus we suggest that its binding to AFP might play a role in the AFP-mediated ovarian regulation previously demonstrated.