[Free radical mechanism of action of pyrimido-triazine antibiotics].
EPR spectra of anion radicals were recorded as a result of chemical or enzymatic reduction at various pH of the pyrimido-triazine antibiotics. These anion radicals easily form superoxide radicals in the presence of oxygen. It is supposed that a higher selectivity of reumycin action is due to difference in the redox potentials of the neutral and ionized antibiotic forms. A possibility of enhance the reumycin potency may involve the pH lowering inside the tumor cells - for example, by glucose injections.
D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000378:metabolism / Q000494:pharmacology*; D004578:Electron Spin Resonance Spectroscopy; D004837:Epinephrine / Q000378:metabolism; D005609:Free Radicals; D066298:In Vitro Techniques; D008862:Microsomes, Liver / Q000378:metabolism; D010084:Oxidation-Reduction; D051381:Rats; D014227:Triazines / Q000378:metabolism / Q000494:pharmacology*
D000903:Antibiotics, Antineoplastic; D005609:Free Radicals; D014227:Triazines; D004837:Epinephrine
Svobodnoradikal'nye mekhanizmy deĭstviia pirimidotriazinovykh antibiotikov.