Possible Interaction: Progesterone and Thyroxine

“Twenty-four-hour estradiol and progesterone secretion into the medium were determined for granulosa cells growing in serum-free … medium with added T4 in a concentration range of 10−7 to 10−11 M.ConclusionsAll concentrations of T4 used produced … in progesterone secretion (range, 1.39 … the baseline amount).”

“Between 48 and 72 h after the initiation of cell culture, oestradiol and progesterone secretion into the medium was determined for granulosa …-free medium with FSH/LH and thyroxine added in a concentration range of 10(-10)-10(-7) M. All concentrations of thyroxine used produced … alone) and progesterone (….”

“and presumably progesterone are capable of suppressing thyroxine production and/or release.”

“A negative significant correlation between progesterone and T4 was revealed in ovarectomized rats.”

“Triiodothyronine (T(3)) and thyroxine (T(4)) have been widely shown to affect ovarian functions and the synthesis of progesterone (P(4)).”

“In experiment 4, T4 (30 ng/ml) increased (to 1.2-fold) progesterone production by granulosa cells only in the presence of FSH and had no effect on aromatase activity.”

“Low doses of T4 (3 to 30 ng/ml) tested in experiment 3 had no effect on aromatase activity but increased (to as much as 1.4-fold) progesterone production by granulosa cells.”

“ Progesterone increased the levels of T3 and decreased the levels of T4 in ovariectomized rats.”

“Estrogen plus progesterone replacement reduced weight gain markedly and increased T3 with normal T4.”

“Furthermore, T4 augmented FSH-mediated production of progesterone and estradiol by immature granulosa cells cultured in vitro.”

“In birds exposed to short days treatment with T4 slightly increased both the concentrations of progesterone , oestrone and oestradiol in plasma and the weight of the ovaries, while ovariectomy increased the testosterone and oestradiol concentrations in plasma.”