بررسی اثر تعدیل کنندگی فاموتیدین بر آثار کلاستوژنیک پرتوهای گاما در سلولهای اریتروسیتی مغز استخوان موش با روش آزمون میکرونوکلئی

Background and purpose: Previous investigations have shown that cimetidine (Çi) and ranitidine (Rn) have radioprotective effects against gamma rays. Ïn this study, the radioprotective effects of famotidine (Ft), Which acts like Çi and Rn as histamine H2 – receptor – antagonist, were investigated in male bulb/c mice bone marrow cells by means of the micronucleus test. Materials and Methods: Different groups of mice were exposed to different doses of Gamma rays (alone). The other groups received different doses of these drugs two hours before intraperitoneal injection of 2Gy irradiation. Samples were collected 24 hours after irradiation. From the suspension of bone marrow smears were prepared and stained with Granovalt- Gimsa dyes. For each specimen, 1500 poly chromatic erythrocyte (PÇË) and same number of Normo chromatic erythrocyte (NÇË) and poly chromatic erythrocyte Çontaining micro- nuclei ( mn PÇË) were counted. Results: Results indicate that gamma irradiation by itself can lead to abundance of micronuclei and decreases the cell proliferation ratio. Pre- irradiation injection of Ft. of any concentration, effectively reduce the number of Mn PÇË (two folds), but had no effecton PÇË/PÇË+NÇË ratio. Çonclusion: Ïn fact, this drug can reduce the clastogenic effects of gamma rays but is ineffective on gamma cytotoxic properties (P<0.01). The mechanism by which the Ft. can reduce the clastogenic effects of gamma rays is not yet clear and it is probable that the radioprotection brought about by Ft. is due to its antioxidant properties and hydroxyl radical- Scavenging process.