In the present study, intestinal
apo A-IV synthesis was investigated using a
carbon tetrachloride (CCl4)-induced
cirrhosis rat model.
Triglyceride (TG) content in rat cirrhotic liver was increased markedly by 170% (P < 0.001) and
apo B was increased by 20% (P < 0.05) compared with control levels. These results reflected the steatotic change in the liver. In contrast, TG levels in the small intestine of cirrhotic rats decreased significantly (P < 0.01). In addition, intestinal
apo A-IV (jejunum P < 0.001; ileum P < 0.01) and its
mRNA levels (jejunum P < 0.01; ileum P < 0.05) were also reduced. The decreased
apo A-IV content in the jejunum was confirmed by immunohistochemical analysis. These results indicate that intestinal
apo A-IV synthesis in
cirrhosis is suppressed, at least under the condition of an overnight fast. Therefore, decreased intestinal
apo A-IV synthesis may relate to the decreased ability to absorb fat in
cirrhosis, but a fat-loading study will be necessary to confirm this hypothesis. It is unknown from the present study why serum
apo A-IV level is not significantly decreased, despite a reduction in
apo A-IV synthesis. The clearance of
apo A-IV by the liver may be delayed or
apo A-IV synthesis may be rather markedly enhanced during fat absorption in
liver cirrhosis.