D-penicillamine metabolism: in vitro studies of S-oxidation mechanisms.

The metabolism of D-penicillamine was studied in vitro using microsomal and cytosolic fractions of liver from DA-strain rats. Formation of inorganic sulphate, presumably via an S-oxidative pathway, was catalysed by both fractions. However, microsomal S-oxidation was higher in female animals than males, the sex differences being reversed with cytosolic fractions. The total yield of inorganic sulphate was similar for both sexes. Cytochrome P-450 isoenzymes did not appear to be directly involved.