[Changes in passive electric tissue properties of experimental tumors during carcinogenesis].

The DS-carcinosarcoma of rats changes its passive electrical properties during the development time. Using a pulse measurement method the pulse parameters h beta and h1 of cancer tissue from 10 rats were measured in vivo during a period of 13 days after the beginning of the tumour growth. These parameters depend on the intra- and extracellular conductivity, on the membrane capacity, and on the volume fraction of the structures surrounded by a membrane. The values of h beta and h1 decrease during the first 4 days of the cancerogenesis by more than 50%. These findings agree with measurements carried out in portiocarcinomas.