Metabolism of cortisol by human thrombocytes

A study was made in order to see whether human thrombocytes are capable to metabolize cortisol. Known concentrations of thrombocytes were incubated with 1.23H-cortisol and the products isolated and identified by t.l.c., paper chromatography, and derivations. Two metabolites were found to be produced by thrombocytes: 20beta-hydroxycortisol and tetrahydrocortisol. The enzymatic nature of the reactions was proved by (1) heat treatment (2) finding out NADPH to be a specific cofactor and (3) the dependence of the activity on the number of thrombocytes in suspensions.