Abstract
Estrogen conversion experiments incubating etradiol, estrone and estriol with human placenta homogenate respectively in an atmosphere of oxygen or nitrogen were studied.
The estrogens were determined by Kober reaction and identified by paper chromatography.
The following results were obtained in these experiments.
1) Estradiol incubated with placenta in an atmosphere of oxygen converted to estrone in large amount, but in an atmosphere of nitrogen converted to estrone in small amount. (Presumably incubating medium dissolve few oxygen.)
2) Incubation of estrone or estriol with placenta in an atmosphere of nitrogen resulted in no conversion to other estrogens. The recovery rate of additional hormones incubated in an atmosphere of nitrogen were lower than in case of oxygen.
3) From the above results, it may be summarized that estrogen level declines in urine or blood in toxemia of late pregnancy depend on oxygen deficiency in placenta.
