[Comparative study of the radiation-protective effectiveness of low doses of cysteamine, heparin, and naphtizine in experiments on mice].

Experiments were conducted on adult random-bred mice. The animals were exposed to a total single gamma-irradiation with a dose of 7.0 Gy (LD90/30). Drugs were administered prophylactically in a wide range of single doses: cystamin from 0.015 to 150 mg/kg, naphtizin from 0.001 to 10 mg/kg, heparin from 0.025 to 500 units/kg. It was found that the dose-effect curve based on the survival parameters of irradiated animals had two-phase character for cystamin and heparin with maxima of efficiency in the field of low and standard dosage of radioprotectors. Antiradiation effect of naphtizin reached maximum at low concentrations and then went on a plateau at usual radioprotective doses.