Investigation of a Corticosteroid-Binding Globulin-Like Molecule in Human Placenta*

Abstract

The existence of an endogenous corticosteroid-binding globulin (CBG)-like molecule in human placenta has been reported in studies which depended largely on immunological techniques. The experiments reported herein do not support that contention. Using a well characterized antibody to purified human CBG, we were unable to demonstrate CBG in placental cytosol. Although the immunological methods were too insensi-tive to detect CBG, the presence of small amounts of it were detected in binding experiments with [(3)H]cortisol. Simultaneous measurement of serum albumin indicated that the presence of CBG in the placental cytosol could be accounted for by contamination of the preparation with plasma.