While in adult human serum, cortisol (F) is present in higher concentrations than cortisone
(E), the reverse has been recognized in fetal serum for two decades. To clarify the
relationship between biologically active F and its inert metabolite E, the interconversion of
these steroids was investigated in various tissues of the human fetus, neonate, child and
adult. Tissues obtained within 48 h of death or surgery were incubated with tritiated F and E
at 37° C for 2 h with and without added substrate in the absence of cofactors. Conversion of …