Activity of 3 -hydroxysteroid dehydrogenase in the postovulatory follicle of the domestic fowl (Gallus domesticus)

Abstract
The activity of .DELTA.5-3.beta.-hydroxysteroid dehydrogenase (3.beta.-HSD) [EC 1.1.1.51] in the postovulatory follicle (POF) of the domestic hen [G. domesticus] was studied; it declined rapidly during the first 15 h after ovulation and then fell gradually until 50 h when there was no detectable activity. Comparison of 3.beta.-HSD and G-6-P dehydrogenase [EC 1.1.1.49] activities in the theca and granulosa cells indicated that the changes in enzymatic activity can be attributed to the thecal component; the enzyme activity in granulosa cells was stable up to 35 h after ovulation. The results appear consistent with the hypothesis that the POF is a source of steroid hormones.