[en] Complete text of publication follows. The radiomodifying effect of peppermint extracts against sublethal and lethal doses of gamma radiation in Swiss albino mice has been explored in our several studies. Peppermint extract (1 g/kg) or peppermint oil (40 ?L/animal) pretreatment decreased serum acid phosphatase and increased serum alkaline phosphatase compared with controls after irradiation, but the levels returned to normal within 5 days. Significant alterations in the intestinal mucosa of mice treated daily with 1 g/kg peppermint extract were observed within 20 days post irradiation at 8 Gy. Compared with controls, peppermint pretreatment increased villus height, total number of cells and mitotic cells, and decreased the number of goblet and dead cells. Oral administration of M. piperita before exposure to gamma radiation was found to be effective in protecting against the chromosomal damage in bone marrow of mice. A significant increase in percentage of chromatid breaks, chromosome breaks, centric rings, dicentrics, exchanges, acentric fragments, total aberrations and aberrations/damaged cell was observed at 12 hr post-irradiation autopsy time in control animals, whereas M. piperita pretreated irradiated animals showed a significant decrease in percentage of such aberrations. Pretreatment with an aqueous extract of peppermint prior to whole body gamma irradiation at 4, 6, 8 and 10 Gy significantly increased the spleen weight and the number of endogenous spleen colonies compared with irradiated mice without pretreatment. A daily oral dose of 1 g/kg administered for 3 days prior to irradiation significantly increased hematological parameters and improved the survival rate compared with irradiated control animals at 10 days post-irradiation. A regression analysis of the survival data in irradiated mice revealed that mice pretreated with peppermint were able to withstand a 1.78-fold higher dose of radiation than untreated mice. A daily oral dose of peppermint oil (40 μL/animal) administered for 3 days prior to irradiation significantly increased hematological parameters (erythrocytes, leukocytes, hemoglobin and hematocrit) compared with controls. Animals pretreated with leaf extract of M. piperita and exposed to 8.0 Gy gamma radiation showed a significant increases in the activities of reduced glutathione content, glutathione peroxidase, glutathione reductase, glutathione S-transferase, superoxide dismutase, and catalase. Irradiated group pretreated with leaf extract of M. piperita showed significant decrease in malondialdehyde formation in liver. The leaf extract of M. piperita showed strong radical scavenging activity in both the DPPH* and ABTS*+ assays. These results suggest the antioxidant and free radical scavenging activities of M. piperita constitute a likely mechanism of radiation protection.