[Studies on steroidogenesis by monolayer culture of human luteal cells of the menstrual cycle (author's transl)].

The purpose of the experiments covered by this report was to see whether or not cell cultures reflect conditions in vivo. We have used mainly the primary cell culture technique of human corpora lutea in TC199 containing 20% fetal calf serum. Steroid concentrations were determined by RIA. As compared with relative low production of estradiol and 17 alpha-hydroxyprogesterone, progesterone (P) production showed a peak of 27.5 +/- 8.7 ng/10(5) cells/ml/2 days on about the sixth day. When the cells were cultured in the presence of hCG, the P concentration (83.9 +/- 13.4) significantly increased and an inhibition in the growth rate of luteal cells was observed. When a drop of suspension of isolated cells was examined under a phase contrast microscope, the cells appeared spherical. In Sudan Black fat staining preparations, numerous lipid granules could be seen in the cytoplasm. Also electromicroscopic studies induced that the cells contained numerous mitochondria and well developed, smooth endoplasmic reticula. The cells exhibited strongly positive 3 beta-hydroxysteroid dehydrogenase activity and the cells on the tenth day culture showed the 46, XX karyotype. As mentioned above, we could show that this in vitro system, namely; monolayer cell culture reflected the conditions in vivo, mainly through P production by luteal cells and the effect of hCG.