Prostaglandin E2 metabolism by human myometrium.
We studied the metabolism of prostaglandin E2 (PGE2) by human myometrium. Incubation of [3H]PGE2 with myometrial homogenates resulted in the formation of three products, which on high pressure liquid chromatography had the chromatographic mobility of PGF2 alpha, 13,14-dihydro-15-oxo-PGF2 alpha (PGFM), and 13,14-dihydro-15-oxo-PGE2 (PGEM). These three metabolites were measured by specific RIA. The production of all three metabolites was stimulated by NADPH and inhibited by NADP. Quantitatively, PGEM was the most important product, followed by PGF2 alpha, and then PGFM. The rates of production of the three metabolites in the presence of saturating concentrations of PGE2 and NADPH were, respectively, 1, 0.5, and 0.15 pmol/mg protein.min. The pattern of metabolism was similar in myometrium from pregnant and nonpregnant women and was not affected by the presence or absence of labor. These data demonstrate that PG-9-oxo-reductase is present in human myometrium. They also suggest that the activity of this enzyme may influence the levels of PGEM and PGFM in the peripheral circulation, particularly during parturition when there is increased intrauterine PG release.
Cañete Soler
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R
University of Oxford, Nuffield Department of Obstetrics and Gynaecology, John Radcliffe Hospital, Headington, United Kingdom.
López Bernal
A
A
Turnbull
A C
AC
D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D015232:Dinoprostone / Q000031:analogs & derivatives; D005260:Female; D006801:Humans; D007743:Labor, Obstetric / Q000378:metabolism; D009215:Myometrium / Q000187:drug effects / Q000378:metabolism*; D009249:NADP / Q000494:pharmacology; D011247:Pregnancy / Q000378:metabolism; D011458:Prostaglandins E / Q000378:metabolism*; D011863:Radioimmunoassay; D013997:Time Factors
D011458:Prostaglandins E; C025087:15-keto-13,14-dihydroprostaglandin E2; D009249:NADP; D015232:Dinoprostone