[Effect of peptone blocking asbestos-induced carcinogenesis in rats]

Regular intraperitoneal administration of peptone to rats was initiated immediately and 12 months after intraperitoneal thrice injection of crokidolite UICC in a dose of 20 mg. The rate of peritoneal mesotheliomas was 37.8% after co-administration of peptone and crokidolite, 25.6% following 12 months of crokidolite injection, and 72.1% after use of crokidolite alone. The effect of peptone administration is accounted for by the action of macrophages on transformed mesothelial cells and mesothelioma cells.