Investigation of a corticosteroid-binding globulin-like molecule in human placenta.

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 insensitive to detect CBG, the presence of small amounts of it were detected in binding experiments with [3H]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.