Uterine blood flow and prostaglandin levels in ovariectomized rabbits

Blood flow (measured by radioactive microspheres) through the uteri of ovariectomized rabbits increased significantly by 2 h, was lower at 4 and 8 h, and returned to control values by 24 h after an injection of 25 microgram oestradiol-17beta. Blood flow through the kidneys was not affected. Concentrations of PGF and PGE in uterine vein blood were elevated after oestrogen treatment. PGF values were significantly greater than control. PGE concentrations, while elevated, were not significantly different from control, although the pattern of release was similar to that of PGF. Pretreatment of animals with progesterone or L11204, or concurrent treatment with indomethacin did not modify the blood flow through the uterus. It is concluded that the increased uterine blood flow seen after oestrogen treatment is not related to prostaglandin production.