Estrone, RIA CT

Radioimmunoassay for the Quantitative Determination of Estrone level in Human plasma or serum.

The origin of plasma estrogens in women has been precisely studied by refined isotopic dilution techniques. In normal women, most plasma estradiol is derived from the ovary, where theca cells secrete androstenedion, which is then converted to estrone and then to estradiol by the granulosa cells.

Estrone in the circulation is essentially bound to albumin. This is important in the interpretation of estrone-assay data. Indeed, and contrary to estradiol, total estrone levels are not significantly modified by SHBG concentration.

Since the concentrations of 125I - E1 and coated antibodies are constant, the advancing state of the equation depends on the concentration of E1.

The amount of 125I - E1 bound to the coated tube is inversely proportional to the concentration of E1 in the sample.

Following the incubation, the tube is washed to remove excess of unbound 125I - E1. Patient samples concentration are read from a calibration curve.