Prostaglandin synthesis by isolated cells of rat uterus: production rates, and effects of indomethacin and histamine

Luminal epithelial and residual cells (mainly of the endometrial stromal tissue) of proestrous rat uteri have been isolated and cultured in defined medium. The prostaglandins produced during a short-term incubation (2 h) in the presence of 10 microM arachidonic acid (to optimize PG production) were determined by direct assay of the culture medium. For the epithelial cells, PGF2 alpha was produced in greatest amounts, followed by 6-keto PGF1 alpha and PGE, while low levels were synthesized by the residual cells. The synthesis of PGF2 alpha by the epithelial cells was inhibited by incorporating indomethacin into the medium and an IC50 value of 2.3 microM was obtained. Incubations performed with histamine in the absence of exogenous arachidonic acid indicated that the pathways for the production of individual prostaglandins were followed to different relative extents, with the production of 6-keto PGF1 alpha being enhanced for both groups of cells when compared to incubations with arachidonic acid.