Abstract
In the present study, we investigated the changes of serum lipoproteins and apolipoproteins (Apo) in rats with acute liver injury induced by carbon tetrachloride (CCl4) or a-naphthylisothiocyanate (ANIT) . Rats were 7 week old, male, Sprague-Dawley. CCl4 or ANIT were dissolved in olive oil, and the final volume given to each animal was adjusted to 2 ml/kg body weight. CCl4 was given orally at a dose of 0.5 ml/kg/day for 4 days. ANIT was given orally in a single dose of 100 to 200 mg/kg. CCl4 decreased the very low density serum lipoprotein (VLDL) level, but did not significantly change the low density lipoprotein (LDL) or the subfractions of high density lipoprotein (HDL), HDL1, HDL2, and HDL3. ANIT decreased VLDL and HDL3, and increased LDL and HDL1. In addition, abnormal lipoproteins, indicated as VLDL' and HDL1', were found after ANIT adiministration. The stained band of VLDL' in the disk electrophoretic gel was found between the origin and VLDL, and HDL1' was found between HDL1 and HDL2. Albumin combined nonesterified fatty acid was increased by CCl4, but decreased by ANIT. CCl4 decreased Apo E and C-I in VLDL and HDL fractions. ANIT increased Apo A-I in the VLDL fraction, Apo E and C-I in HDL fractions. ANIT caused swelling of hepatocytes, but did not cause the hepatocyte necrosis nor fat deposition. The results suggest that decrease of VLDL, Apo E and Apo C-I by CCl4 administration was due to the inhibition of apoprotein synthesis in the liver associated with liver injury, and appearance of abnormal lipoproteins after ANIT administration was due to the abnormality of lipoprotein formation in the liver associated with cholestatic liver injury.
