Effects of cortisol on the amounts of estradiol-17β and progesterone secreted and the number of luteinizing hormone receptors in cultured bovine granulosa cells

Abstract

The direct effects of cortisol upon the amounts of estradiol-17β and progesterone secreted, and the number of luteinizing hormone (LH) receptors in cultured bovine granulosa cells were examined. Granulosa cells from small bovine follicles (diameter 3–7 mm) were successfully cultivated in a 1:1 mixture of Dulbecco's modified Eagle's medium and Ham's F-12 nutrient medium containing 10% fetal calf serum for the first day and subsequently incubated with follicle stimulating hormone and testosterone in serum-free medium for up to 8 days. The cells increased their output of both estradiol and progesterone during 9 days of culture. The addition of cortisol in the range 0.1–10 μM did not significantly change the total DNA content of the granulosa cells. Cortisol treatment caused a significant decrease in the amount of estradiol-17β secreted by granulosa cells ( P<0.05). Cortisol also significantly decreased the number of LH receptors in the cultured granulosa cells in a dose-dependent manner ( P<0.05). In contrast, cortisol tended to increase progesterone production by granulosa cells. These results demonstrate the direct inhibitory effect of cortisol on follicular secretion of estradiol-17β and LH receptor content. This observation is consistent with the hypothesis that cortisol released by stress may directly inhibit the functional maturation of the bovine follicles.