Changes in prostaglandin levels in the sensitized and non-sensitized uterus of the mouse after the intrauterine instillation of oil or saline

Intrauterine instillation of oil, but not saline, induced both a decidual cell reaction and a marked elevation in the uterine PGF-alpha content of suitably sensitized ovariectomized mice. Uterine PGF-alpha concentrations were elevated within 5 min of the oil instillation, reached maximal levels within 30-60 min and then declined to near baseline levels again by 3 h. A similar increase in uterine PGF-alpha content in response to oil instillation was seen in non-sensitized females, although no decidual cell reaction developed. No significant changes in PGE or 6-oxo-PGF-1 content were observed. These results suggest that although the increase in uterine PGF-alpha content is not solely due to the distension of the uterus after intrauterine injection, the increase is not necessarily sufficient to induce a decidual cell reaction.