Protective effect of Thuja occidentalis against radiation-induced toxicity in mice.

The effect of Thuja occidentalis against damage induced by gamma radiation was studied. Whole-body exposure of Swiss albino mice to gamma-rays (6 Gy) reduced the total white blood cell count to 1900 cells/mm(3) on the third day, which was elevated to 2050 cells/mm(3) by the administration of alcoholic extract ofT occidentalis (5 mg/dose/animal, intraperitoneally). Six animals from each group were killed after 2, 7, and 11 days of irradiation to detect the bone marrow cellularity and radiation-induced toxicity. The number of bone marrow cells and alpha-esterase positive cells in control animals after 11 days was reduced to 12.2 x 10(6) cells/femur and 693.5/4000 cells, respectively. In T occidentalis-treated animals, bone marrow cellularity was increased to 16.9 x 10(6) cells/femur and alpha-esterase positive cells were 940/4000 cells, a nearly normal level. Alcoholic extract of T occidentalis reduced the elevated levels of GPT and alkaline phosphatase in liver and serum after irradiation. The lipid peroxidation levels were also lowered in the irradiated animals treated with the Thuja extract.