α-glutathione s-transferase (α-GST) release,an early indicator of carbon tetrachloride hepatotoxicity in the rat

Abstract

1 The use of the cytoplasmic enzyme, alpha glutathione s-transferase (α-GST) as an early index of carbon tetrachloride (CCl₄) toxicity in the rat was investigated and compared with a standard enzyme marker, aspartate aminotransferase (AST). The hepatotoxic effects of CCl ₄ in the rat were determined in a time and dose-response study.

2 Following CCl ₄ exposure, α-GST release was shown to be an earlier and more sensitive biomarker of hepatotoxicity than AST.

3 Significant increases in α-GST were detected 2 h after CCl₄ exposure. Using the enzyme marker AST, this early hepatotoxic injury went undetected. At 6 and 16 h, α-GST was also a more sensitive indicator of hepatotoxicity than AST.

4 α-GST release was significantly increased at a dose of 5 μl/kg, the lowest concentration of CCl₄ administered and clearly responded in a dose-dependent manner with increasing doses of CCl₄. In contrast, release of AST did not reach statistical significance until a dose of 25 μl/kg.

5 Thus, these findings indicate that α-GST is a more sensitive and more accurate reflector of CCl₄ induced hepatotoxicity than AST.