Protective effect of RH3 with special reference to radiation induced micronuclei in mou se bone marrow

Elfect uf pre-irradiation admini stra tion of different doses of RI-I-3, the herbal preparation of an Indian Ill edi c in ~tl plalll Hippoplwe ,." aJIIl/oides, 30 min before lOGy whol e body gamma irrad iation was studi ed. Doses between 25 to 35 mg/kg body wt. were found to render > 80 % survival in mice. In order to in ves ti gate whether RI-I -3 protec ted against radiation induccd gcnotox ieit y, mice werc admini stcrcd diffcrent doscs of RII-3, 30 min beforc 2 Gy dose and compared with un trca ted, RI-I-3 treated and irradiatcd controls. Thc bone marrow cell s wc rc co ll ec ted at different timc interva ls fo llow ing vari ous trca tmcnts and processed fO I· scoring micronuclei (MN). Admini strat ion of RI-I -3 alonc did not cnhance the MN frcqucncy as compared to the contro l, and racliJti on dose of 2 Gy signifi cantl y cnhanced the MN frequcncy (3.1 %, P < 0.0 I ). Preirradiation treatmcnt with RI-I -3, however, reduccd thc rad iat ion induccd M N frequency in a drug dose dcpendent man ncr suggcsting its rad ioprotect ive cffi cacy. The prot cc ti vc effect of RI-I-3 0 11 radiati ol1 induccd perturba ti ons in cell cyc lc progress ion 11 :1 , st udicd flowcytoillctr ica ll y in mousc bone marrow cc ll s. RI-I -3 trcatmclll (30 mg/kg body wt.) enhanced DNA synthcsis (S-phasc) in unirradiated controls Jnd also countcrcd rad iat ion induccd depression of S-phase to facil ita lc rcplcnishmcnt of cells lost due 10 radial ion injury.