Effect of the aromatase inhibitor CGS-16949A on pregnancy and secretion of progesterone, estradiol-17beta, prostaglandins E and F2alpha (PGE; PGF2alpha) and pregnancy specific protein B (PSPB) in 90-day ovariectomized pregnant ewes

Prostaglandins Other Lipid Mediat. 2001 Sep;66(2):77-88. doi: 10.1016/s0090-6980(01)00144-7.

Abstract

The aromatase inhibitor CGS-16949A was used to determine whether CGS-16949A altered secretion of progesterone, estradiol-17beta, PGE (PGE1 + PGE2), PGF2alpha and PSPB. Ninety day pregnant ewes were ovariectomized and received vehicle, PGF2alpha, CGS-16949A or PGF2alpha+CGS-16949A. None of the ewes treated with PGF2alpha, CGS-16949A or PGF2alpha+CGS-16949A aborted (P > or = 0.05) during the 108-h experimental period. Treatment with CGS-16949A lowered (P < or = 0.05) progesterone in jugular venous plasma but concentrations of progesterone were not affected (P > or = 0.05) by treatment with PGF2alpha. Concentrations of estradiol-17beta and PSPB in jugular venous plasma and PGE in inferior vena cava plasma were decreased (P < or = 0.05) by treatment with CGS-16949A. Concentrations of PGF2alpha in inferior vena cava plasma were not affected (P > or = 0.05) by treatment with CGS-16949A. Decreases in estradiol-17beta occurred before decreases in PSPB, which was then followed by decreases in PGE (P < or = 0.05). It is concluded that these data support the hypothesis that estradiol-17beta regulates placental secretion of PSPB; PSPB regulates placental secretion of PGE; and PGE regulates placental secretion of progesterone during mid-pregnancy in ewes.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Animals
  • Aromatase Inhibitors*
  • Aspartic Acid Endopeptidases / metabolism*
  • Dinoprost / metabolism*
  • Enzyme Inhibitors / pharmacology*
  • Estradiol / metabolism*
  • Estrogen Antagonists / pharmacology
  • Fadrozole / pharmacology*
  • Female
  • Ovariectomy
  • Pregnancy
  • Pregnancy Proteins / metabolism*
  • Progesterone / metabolism*
  • Prostaglandins E / metabolism*
  • Sheep

Substances

  • Aromatase Inhibitors
  • Enzyme Inhibitors
  • Estrogen Antagonists
  • Pregnancy Proteins
  • Prostaglandins E
  • Progesterone
  • Estradiol
  • Dinoprost
  • Aspartic Acid Endopeptidases
  • pregnancy-associated glycoprotein 1
  • Fadrozole