Estradiol dehydrogenase activity in the Fallopian tube during the normal menstrual cycle

Simultaneous determinations of 17 beta-estradiol dehydrogenase activity (17 beta-HSDH) and of estradiol (E2), estrone (E1), and progesterone (P) were made in homogenates of human tubal tissue. The oviducts were obtained from 16 multi-parous normal women who requested sterilization; surgery was performed at different phases of the menstrual cycle. A significant decrease of E2 concentration with a concomitant increase of E1 was observed in the secretory phase of the cycle. The activity of 17 beta-HSDH was highest in the early secretory phase of the cycle with a significant difference (p less than 0.05) from the proliferative phase values. The results support the concept, that the activity of 17 beta-HSDH in the oviduct is regulated by progesterone.