Clenbuterol plus acivicin decrease tumor growth and increase muscle mass in rats maintained on total parenteral nutrition.

Two problems associated with supplemental nutrition of tumor-bearing organisms are control of tumor growth and reduction of cachexia. To investigate these problems, rats bearing methylcholanthrene-induced sarcomas were maintained on total parenteral nutrition (TPN) for 10 to 12 days beginning 23 days after tumor inoculation. Combined treatment of one group of these rats with the glutamine antimetabolite, acivicin, and the beta 2-adrenergic agonist, clenbuterol, arrested tumor growth, increased skeletal muscle mass and protein content, increased gut mass, and decreased total plasma lipid levels. Resting energy expenditure and cardiac mass were increased by TPN and were increased further by acivicin plus clenbuterol. These results demonstrate that tumor growth and muscle wasting can be controlled during TPN of tumor-bearing organisms. Therefore, cachectic depletion of lean body tissue may not be obligatory in neoplastic disease.