URINARY AND SERUM MUTAGENICITY STUDIES WITH RATS BEARING EXPERIMENTAL-TUMORS

Urine and serum samples of rats bearing three different experimental t umours (hepatocellular carcinoma, myelomonocytic leukemia and mesoblas tic nephroma) were investigated for mutagenicity with the Ames Salmone lla test. Enhancement of mutagenic activity in TA98 and TA100 was obse rved only in the case of urine samples obtained from animals bearing n ephromas. Mutagenicity increased with increasing time after implantati on of tumours. There was no coincidence between urinary and serum muta genicity under the experimental conditions employed. Further studies a re needed to determine the origins, and chemical and genotoxic charact eristics of urinary mutagens. In addition, the question as to whether any mutagenic substances can be detected in fractions of plasma/serum should also be experimentally addressed.