Conversion in vitro of prostaglandin endoperoxide into prostaglandins by arteries from pregnant and non-pregnant human uteri.

The enzymatic and non-enzymatic conversion in vitro of the prostaglandin endoperoxide (PGH2) into prostaglandins and thromboxane by human uterine arterial tissue was investigated. Segments of uterine arteries were obtained from six pregnant and six non-pregnant women. Slices of tissue were incubated with isotopically-labelled PGH2 and the products formed were determined by means of thin-layer chromatography. Only PGF2 alpha and PGI2 were formed by enzymatic conversion. Uterine arterial tissue from pregnant women produced significantly more PGF2 alpha than tissue from non-pregnant women, whereas no significant difference in formation of PGI2 could be demonstrated.