EFFECT OF VALINE-DEPLETED TOTAL PARENTERAL-NUTRITION ON FATTY LIVER DEVELOPMENT IN TUMOR-BEARING RATS

Valine-depleted amino acid imbalance, while having a suppressive effec t on tumor growth, may induce fatty liver. We administered valine-depl eted total parenteral nutrition (TPN) solution to rats subcutaneously transplanted with ascites containing hepatoma AH-109A and examined the time course of the development of fatty liver. An accumulation of fat ty vacuoles was observed in hepatocytes on day 4. To prevent the devel opment of fatty liver in tumor-bearing rats, we administered a small a mount of valine in addition to the valine-depleted imbalance solution via the central vein. Such treatment, however, resulted in neither the prevention of fatty liver development nor the suppression of tumor gr owth. To supply valine to the liver, we administered a low concentrati on of valine via the portal vein simultaneously with central venous ad ministration of valine depleted TPN solution. As a result, the periphe ral blood valine level of these rats was < 0.5 that of the control gro up, but the valine in the liver was maintained at the same level as th at of the control group, and accumulation of triacylglycerols in the l iver was slight. However, the suppressive effect on tumor growth was m aintained, as the tumor weight was suppressed to almost the same degre e as that of rats administered only the valine-depleted solution. (C) Elsevier Science Inc. 1998.