Cell membrance ionic permeability and mitochondria changes during 4-dimethyl-aminoazobenzene carcinogenesis.

In rats fed 4-dimethylaminoazobenzene there is an increase of calcium and sodium in liver accompanied by a decrease of magnesium and potassium. This influx of extracellular cations is explained as the result of cell membrane modifications due to the carcinogen action. Mitochondria show the highest calcium content at the time of maximum tumor incidence. The interrelation between cell membrane permeability changes and mitochondria damage through calcium overloading as a cancer triggering event is discussed.