Studies on biscoclaurine alkaloids in relation to radiation damage of hemopoietic tissue Ⅱ. Effect of cepharanthin on the recovery from radiation damage in mouse hemopoietic tissue

After a whole-body irradiation at a single dose of 500R, mice were injected intraperitoneally with 0.1mg of cepharanthin (CR)every day for 20days. Endogenous spleen colonies (CFU-S) were counted on Day 10, and the spleen and thymus weight was measured, peripheral leukocytes counted and hematocrit value determined for 30days after the irradiation. The number of CFU-S increased remarkably in CR injected mice compared with control mice. Decreased spleen weight by irradiation recovered in excess by Day 30. In CR administered mice, the spleen weight increased transitorily along with the proliferation of CFU-S. After irradiation, the recovery of thymus weight was delayed compared with the spleen. Therefore, the effect of CR administration was not clear. Peripheral leukocytes decreased in number successively essively up to Day 10 and recovered linearly from Day 20 through Day 30, especially in CR injected mice. The hematocrit value was reduced to a minimum on Day 10 and almost recovered by Day 20 in irradiated mice. CR had no effect on the hematocrit value. The effect of cepharanthin was discussed in relation to radiation damage of hemopoietic tissue.