Changes in cytosolic and nuclear estradiol receptors of normal fallopian tube throughout the menstrual cycle

During the normal menstrual cycle, the changes in estradiol binding to cytosol and nuclear receptors of ampulla. isthmus and fimbria were analyzed. Cytosol estradiol receptor concentration showed little variation throughout the cycle, but were higher at the periovulatory phases. The concentration of nuclear estradiol receptor markedly varied in isthmus and ampulla; being significantly higher at the late proliferative phase than at the secretory phases. A positive linear correlation between nuclear receptor content and plasma estradiol concentration was observed, while a negative one was found with plasma progesterone.