Advantage of serum type-I arginase and ornithine carbamoyltransferase in the evaluation of acute and chronic liver damage induced by thioacetamide in rats

Background: We evaluated the usefulness of serum type-I arginase (ARG) and ornithine carbamoyltransferase (OCT) in thioacetamide (TAA)induced acute and chronic liver injury in rats. Methods: In an acute injury model, we measured the time-courses of serum concentrations of ARG and OCT using ELISA, together with AST and ALT using biochemical enzymatic assays after a single administration of TAA (200 mg/kg, i.p.). In the chronic model, TAA was repeatedly administered (20 mg/kg/day, p.o.) for 16 weeks and serum concentrations of the enzymes were evaluated. Results: In the acute model, the concentrations of the enzymes were increased in a similar manner, peaking 24 h after the administration, and ARG showed the earliest and greatest increase among the enzymes tested. In the chronic model, the serum concentration of OCT was significantly increased only I week after oral treatment, while concentrations of the other enzymes were increased at 8 to 12 weeks. In the histological analysis, TAA treatment damaged hepatocytes in both the acute and chronic model. Conclusions: These results clearly show the usefulness of ARG and OCT for the evaluation of acute and chronic liver injury, respectively. (c) 2006 Elsevier B.V. All rights reserved.