Results of genotoxicity testing of theophylline on bacteria and two lines of mammalian cells.

In study of the genotoxic effects of theophylline, this substance was subjected to a series of tests. Its potential mutagenicity was followed at the level of both bacteria and mammalian cells. The capacity of the substance to damage human DNA was determined by the so-called DNA inhibition test and by the method of alkaline elution of DNA.

Occurrence of induced 6-thioguanine-resistant colonies in synchronized V79 cells after treatment with ftorafur. Effects of the S9 fraction.

The capacity of ftorafur to induce resistance to 6-thioguanine in V79 hamster cells was investigated. The treatment conditions were arranged in order to favor the induction of such gene mutations. The synchronous cells were treated in the beginning of S phase, i.

The genetic effects of the cytostatic drug TS160 on Chinese hamster fibroblasts in vitro.

The cytostatic agent TS160 inhibited DNA synthesis in V79 cells while the course of RNA synthesis and protein synthesis were not changed significantly. DNA inhibition was in direct correlation with the inhibition of growth and reduction of colony-forming ability in the treated cells. The study of the mutagenic consequences of single or repeated TS160 treatments showed that TS160 had a significant mutagenic activity on Chinese hamster V79 cells.

Mutagenic effects of nitrofurylacrylic acid on V79 cells under hypoxic conditions.

Induction of 6-thioguanine-resistant mutations was studied in Chinese hamster V79 cells treated with nitrofurylacrylic acid under aerobic and hypoxic conditions. The results obtained demonstrated that the mutagenic activity of this substance, less significant in aerobic conditions, was very high under hypoxic conditions. A gradual increase in mutation frequencies according to the applied concentrations of nitrofurylacrylic acid was observed, the maximal values being at 0.