Estradiol-17 beta inhibition of lutropin and dibutyryl cyclic AMP induced steroidogenesis in intact bovine luteal cells. Absence of effect on induced protein phosphorylations

Altered steroidogenic activity of human granulosa-lutein cells at different cell densities in culture

In the present study, the relationship between human granulosa-lutein cell (hGLC)-plating density and steroidogenic activity was evaluated. Increasing hGLC-plating density 32-fold, from 0.25 x 10(4) to 8 x 10(4) cells/well, was associated with a concomitant increase in the total amount of progesterone (P4), testosterone (T), and estradiol-17 beta (E2) secretion. The daily amount of each steroid (P4, T, and E2) secreted by hGLC at different cell-plating densities was further normalized per 10(3) cells. Thus, an increase in hGLC-plating density from 0.25 x 10(4) to 1 x 10(4) cells/well was associated with approximate increases of 1.3-fold in P4 and 3-fold in T and a 50% decrease in E2 secretion, per 10(3) cells. A further increase in hGLC-plating density, from 1 x 10(4) to 8 x 10(4) cells/well, was associated with a significant decrease of approximately 3.7-fold in P4 and 6-fold in T per 10(3) cells. A similar increase in hGLC-plating density was associated with no change or a 2-fold decrease, per 10(3) cells, in E2 secretion during days 0-3 or days 3-5 of culture, respectively. The P4/E2 ratio was increased and the E2/T ratio decreased with extension of the culture period. These two ratios had a tendency to be altered inversely, concurrent with the increase in cell-plating densities. At 1-2 x 10(4) cells/well, P4/E2 was maximal, whereas E2/T was minimal.(ABSTRACT TRUNCATED AT 250 WORDS)

Prostaglandin F2 alpha, oxytocin and progesterone secretion by bovine luteal cells at several stages of luteal development: effects of oxytocin, luteinizing hormone, prostaglandin F2 alpha and estradiol-17 beta

Bovine luteal cells from Days 4, 8, 14 and 18 of the estrous cycle were incubated for 2 h (1 x 10(5) cells/ml) in serum-free media with one or a combination of treatments [control (no hormone), prostaglandin F2 alpha (PGF), oxytocin (OT), estradiol-17 beta (E) or luteinizing hormone (LH)]. Luteal cell conditioned media were then assayed by RIA for progesterone (P), PGF, and OT. Basal secretion of PGF on Days 4, 8, 14 and 18 was 173.8 +/- 66.2, 111.1 +/- 37.8, 57.7 +/- 15.4 and 124.3 +/- 29.9 pg/ml, respectively. Basal release of OT and P was greater on Day 4 (P less than 0.01) than on Day 8, 14 and 18 (OT: 17.5 +/- 2.6 versus 5.6 +/- 0.7, 6.0 +/- 1.4 and 3.1 +/- 0.4 pg/ml; P: 138.9 +/- 19.5 versus 23.2 +/- 7.5, 35.4 +/- 6.5 and 43.6 +/- 8.1 ng/ml, respectively). Oxytocin increased (P less than 0.01) PGF release by luteal cells compared with control cultures irrespective of day of estrous cycle. Estradiol-17 beta stimulated (P less than 0.05) PGF secretion on Days 8, 14 and 18, and LH increased (P less than 0.01) PGF production only on Day 14. Prostaglandin F2 alpha, E and LH had no effect on OT release by luteal cells from any day. Luteinizing hormone alone or in combination with PGF, OT or E increased (P less than 0.01) P secretion by cells from Days 8, 14 and 18. However on Day 8, a combination of PGF + OT and PGF + E decreased (P less than 0.05) LH-stimulated P secretion. These data demonstrate that OT stimulates PGF secretion by bovine luteal cells in vitro. In addition, LH and E also stimulate PGF release but effects may vary with stage of estrous cycle.

Ovarian stromal and luteal tissue prostaglandins, 17 beta-estradiol, and progesterone in relation to the phases of the menstrual cycle in women

The concentrations of prostaglandin F2 alpha, prostaglandin E2, the 15-keto-13, 14-dihydro-metabolite of prostaglandin F2 alpha, progesterone, and 17 beta-estradiol were measured in 31 ovarian stromal tissue and 18 luteal tissues. Tissue samples were obtained during abdominal hysterectomy. The ovarian stromal tissue prostaglandin F2 alpha content during the late secretory and early proliferative phases was significantly higher (p less than 0.001) than in tissues obtained during any other phases of the menstrual cycle. The ovarian stromal tissue prostaglandin E2 content was significantly elevated (p less than 0.01) during the late proliferative and early secretory phases. The content of the prostaglandin F2 alpha metabolite also was elevated (p less than 0.001) in ovarian stromal tissues obtained during the late proliferative and early secretory phases. Comparison of the concentrations of prostaglandins and sex steroids in ovarian stromal and luteal tissues indicate the latter to be far more active in terms of steroid and arachidonate metabolism. During the early luteal phase, when the luteal progesterone content was at its highest, both luteal and ovarian stromal tissue contents of prostaglandin E2 were also elevated. The late secretory phase of the menstrual cycle was characterized by lowered luteal progesterone content and a markedly elevated level of prostaglandin F2 alpha in luteal and ovarian stromal tissues. During cyclic ovarian activity in the woman, prostaglandin E2 predominated during the periovulatory phases while the period of luteal death was highlighted by the elevated prostaglandin F2 alpha content in ovarian stromal and luteal tissues.