Induction of glutathione S-transferases A, B and C in rat liver cytosol by trans-stilbene oxide.
The cytoplasmic glutathione S-transferase activity of rat liver has been shown to increase to 300--400% of control values after treatment of the animals with trans-stilbene oxide and this phenomenon has been further characterized in the present study. Quantitative immunological determinations showed that the content of glutathione S-transferases A, B and C together constituted 4.5% of the soluble proteins in the hepatic cytoplasm of untreated rats. The content rose to 12.9 and 17.4% after treatment with trans-stilbene oxide or a combination of trans-stilbene oxide, 3-methylcholanthrene and phenobarbital, respectively. It was demonstrated that the cytosolic fraction from induced liver contains 4.2 times as much antigen which can be precipitated with antiglutathione S-transferase B antiserum as does control cytosol. Antiglutathione S-transferase C, which intereacts with transferases A and C, precipitates 3.3 times as much protein from the induced cytosol compared with control. Crossed immunoelectrophoresis and purification demonstrated that both A and C are increased in amount after treatment with trans-stilbene oxide. Thus, cytosolic glutathione S-transferases A, B, and C in liver are all induced by treatment of rats with trans-stilbene oxide. Immunological crossreaction, similar behavior during chromatography on CM-cellulose and hydroxyapatite and similar specific activities suggest that the control and induced enzymes are essentially identical, trans-Stilbene oxide was found to serve as a relatively poor second substrate for glutathione S-transferases A, B and C and can thus be said to cause substrate induction of these enzymes.
D000818:Animals; D000937:Antigen-Antibody Reactions; D002852:Chromatography, Ion Exchange; D003600:Cytosol / Q000201:enzymology; D004587:Electrophoresis, Agar Gel; D004790:Enzyme Induction; D000939:Epitopes; D005982:Glutathione Transferase / Q000096:biosynthesis* / Q000302:isolation & purification / Q000378:metabolism; D007122:Immunoelectrophoresis; D008099:Liver / Q000201:enzymology*; D008297:Male; D051381:Rats; D013267:Stilbenes / Q000494:pharmacology*
D000939:Epitopes; D013267:Stilbenes; D005982:Glutathione Transferase