Effects of oestradiol and progesterone on the synthesis of DNA and the anti-haemophilic factor VIII antigen in human endometrial endothelial cells in vitro: a pilot study.

The effect of various concentrations of oestradiol and progesterone on DNA synthesis in endometrial endothelial cells derived from human decidua has been studied in vitro by means of a microfluorometric technique and [3H]thymidine incorporation. Oestradiol in concentrations of 10-40 ng/ml was found to significantly stimulate DNA synthesis in the cells whereas progesterone significantly decreased the incorporation of [3H]thymidine. A highly significant correlation (P less than 0.01) was found in the oestrogen-treated samples between the [3H]thymidine incorporation and the ethidium bromide fluorescence after the removal of RNA. No such correlation was found in the progesterone-treated samples. A microfluorometric assessment of the anti-haemophilic antigen Factor VIII following immunofluorescence labelling suggested an increase in the synthesis of this factor after oestradiol treatment whereas progesterone administration did not show any effect. Although no direct extrapolation can be made from the results of the in vitro studies to in vivo conditions the endothelial cell culture system provides a useful model for testing the effect of mitotic mediators and compounds interfering with intracellular protein synthesis. It may therefore contribute to a better understanding of the bleeding mechanism.