gp130 in hepatocytes is essential for IL-6–dependent protection in Con A–induced hepatitis. Con A hepatitis was induced by intravenous injection of 32.5 mg/kg Con A in wild-type (gp130^LoxP/LoxP) and hepatocyte-specific gp130-null (alfpCre gp130^LoxP/LoxP) mice. Mice were pretreated for 3 hours with NaCl (solid line) or IL-6 (200 μg/kg) (dotted line) before i.v. injection of Con A. Liver injury was quantified by detection of AST. (A) Time course of AST serum levels during Con A–induced hepatitis in wild-type mice pretreated with NaCl (solid line) or IL-6 (dotted line). ^#P < 0.01 and *P < 0.05 vs. corresponding IL-6–pretreated wild-type control group at the same time point. (B) Time course of AST serum levels during Con A–induced hepatitis in alfpCre gp130^LoxP/LoxP mice pretreated with NaCl (solid line) or IL-6 (dotted line).