Total parenteral nutrition for maintenance of growth, carcass mass and positive nitrogen balance in rats with a small transplantable tumor.

This study evaluates the effects of 13 days of total parenteral nutrition (TPN) on body weight, carcass mass and nitrogen balance in rats with and without a transplanted Morris No. 7777 hepatoma. Groups of rats without a tumor as well as rats with a tumor of about 3% of body weight or less were shown to maintain carcass weight as well as maintain a positive nitrogen balance when fed totally by vein. The present experiment was done under the same conditions as a previously reported experiment except that the size of the tumor in the rats was considerably smaller. These past studies showed that as the hepatoma gets much larger than 3% of the body weight, it was inhibitory to carcass weight gain even when the rats were given TPN. Thus, the size of the tumor influences the ability of TPN to sustain carcass weight.