Radioimmunoassay of plasma ligandin: a sensitive index of experimental hepatocellular necrosis.

The development of sensitive and specific radioimmunoassay for ligandin, a protein present in abundance in the hepatic cytoplasm, has permitted measurement of ligandin in rat plasma. Plasma ligandin levels were estimated in normal, carbon tetrachloride (CCl4)-treated, and bile duct-ligated rats, with parallel estimation of serum glutamic oxaloacetic transaminase (SGOT). Plasma ligandin levels rose at a greater rate and to higher levels than did SGOT in CCl4-treated rats and showed a more linear increment to increasing doses of CCl4. A marked depletion of hepatic, but not renal ligandin, was associated with CCl4 poisoning. Twelve hours after acute bile duct ligation, both plasma ligandin and SGOT were moderately elevated, plasma ligandin returning to normal by 24 hr, at which time SGOT was still raised. The findings of this study indicate that plasma ligandin is a sensitive index of experimental hepatocellular necrosis.