THE RADIOPROTECTIVE EFFECTS OF WR-2721 IN MICE EXPOSED TO SUBLETHAL OR LETHAL FRACTIONATED DOSIS OF GAMMA- RADIATION

摘要

The radioprotective agents with sulphur have a sulphydryl groups that are able cath a free radicals when are present in organism in irradiation time. The optimal radioprotec-tion is dependent on dose and way of radioprotective agent administration. The majority of radioprotective agents have a maximum radioprotective effect close to dose when express side toxical effects. WR-2721 have a small toxicity close to high dose reduction factor (to DRF=2.7). The radioprotective agent WR-2721 (Ethyol) is used in clinical medicine for radioprotection of nontumorous cells against effects of ionising radiation and cytostatic drugs in present time. In our experiment, the mice were exposed to sublethal or lethal fractionated doses (5×1 Gy to 5 Gy) of gamma-radiation aplicated in course of 5 days. The radioprotective drug WR-2721 in doses 50 mg/kg i.p. or 300 mg/kg i.m. 20 min before irradiation was administered. The radioprotective effect accorging modifications of haemopoietic stem cell function indicators, peripheral blood cells changes and survival of experimental animals, was investigated. Our findings indicate that radioprotective effectivity of WR-2721 is dependent partly on doses of fractionated irradiation partly in dose of radioprotective drug. Abbreviations: CFU-S - colony-forming units-spleen, WBC -white blood cells, BM - bone marrow, DRF - dose reduction factor.