Prostaglandin production by calvariae from sham operated and oophorectomized rats: effect of 17 beta-estradiol in vivo.
The mechanism by which estrogen inhibits bone resorption in vivo is not known. Since prostaglandin E2 (PGE2) is a potent stimulator of bone resorption in vitro, we tested the hypothesis that estrogens might affect bone indirectly by inhibiting endogenous PGE2 synthesis. Cultured parietal bones from 7- to 9-week-old rats showed a gradual release of immunoreactive PGE2 in vitro. Oophorectomy resulted in a two-fold increase in PGE2 release. Treatment in vivo with low doses of 17 beta-estradiol or high doses of 17 alpha-estradiol 26 h and 2 h prior to sacrifice inhibited bone PGE2 release in vitro. Addition of 17 beta-estradiol to calvariae in vitro did not affect PGE2 release, whereas cortisol inhibited PGE2 release.
Feyen
J H
JH
Raisz
L G
LG
D000818:Animals; D001842:Bone and Bones / Q000187:drug effects / Q000378:metabolism*; D015232:Dinoprostone; D004958:Estradiol / Q000494:pharmacology*; D005260:Female; D006854:Hydrocortisone / Q000494:pharmacology; D010052:Ovariectomy; D011458:Prostaglandins E / Q000096:biosynthesis*; D051381:Rats; D011919:Rats, Inbred Strains
D011458:Prostaglandins E; D004958:Estradiol; D015232:Dinoprostone; D006854:Hydrocortisone