Determination of glutathione transferase (GSTT1-1) activities in differenttissues based on formation of radioactive metabolites using S-35-glutathione

A new system has been developed to determine enzyme activities of glutathio ne transferase theta (GSTT1-1) based on radiometric product detection resul ting from the enzymic reaction of methyl chloride with S-35-labelled glutat hione. In principle, the method is universally applicable for determination of glutathione transferase activities towards a multiplicity of substrates . The method distinguishes between erythocyte GSTT1-1 activities of human ' non-conjugators', 'low conjugators' and 'high conjugators'. Application to cytosol preparations of livers and kidneys of male and female Fischer 344 a nd B6C3F1 mice reveals differential GSTT1-1 activities in hepatic and renal tissues. These ought to be considered in species-specific modellings of or gan toxicities of chlorinated hydrocarbons.