[Morphologic study of renal carcinogenesis in rats induced by dimethylnitrosamine].

109 five-month-old albino non-inbred male rats received a single i.p. injection of dimethylnitrosamine (20 mg/kg b.w.) for selective induction of renal epithelial tumors. Forty controls were injected isotonic solution. The animals were autopsied 3-12 months later. Renal cell adenomas were found in 5 rats, mesenchymal renal--6. Renal tumor incidence increased during the experiment reaching 38.5% at month 12. No tumors were detected in controls. To summarize, our experiment failed to induce renal cell tumors only.