Changes in chick oviduct chromatin antigenicity following estrogen withdrawal

A microcomplement fixation assay was used to study changes in the antigenicity of chick oviduct chromatin following estrogen withdrawal. Our findings indicate that following estrogen withdrawal, chromatin from previously stimulated oviducts lost those antigenic determinants which were characteristic of the stimulated state. Withdrawal did not, however, result in the reappearance of antigenic sites characteristic of the unstimulated oviduct. These results suggest that estrogen stimulation of the immature chick results in an irreversible alteration of the oviduct chromatin.