Effects of Testosterone and Estradiol-17.BETA. on Progesterone Production by Granulosa Cells of the Hen.

Abstract

The aim of the present study was to examine the effect of testosterone (T) and estradiol-17β (E2), known as being produced in the theca cells, on the production of progesterone (P4) by granulosa cells of the hen. When granulosa cells isolated from the largest preovulatory follicle (F1) were incubated for 4 hr with increasing doses of ovine luteinizing hormone (oLH), T or E2, P4 production by granulosa cells was increased in a dose-dependent manner by oLH, but not by T or E2. However, when F1 granulosa cells cultured for 48 hr in a monolayer culture system were cultured for an additional 48 hr with increasing doses of oLH, T or E2, not only oLH but also T stimulated P4 production of granulosa cells in a dose-related manner while E2 alone had no effect on P4 production. In addition, when the time course of P4 production by F1 granulosa cells in response to oLH and T was examined for 48 hr during 48 to 96 hr of culture, P4 production with oLH was found to be increased at 4 hr of culture, with the maximal level at 6 hr, while P4 production with T increased significantly from 12 hr of culture, with the maximal response at 36 hr. Furthermore, when F1 granulosa cells were precultured with E2 for various times before 4 hr culture with oLH at 96 hr of culture, the increase in P4 production in response to oLH was only found at a pretreatment time of more than 12 hr.These results indicate that, in granulosa cells of the hen, T may have a direct stimulatory action over the long term on P4 production, and E2 in long-term action may enhance the sensitivity to LH for P4 production.