Abstract: AIM: To study the therapeutic effect of herbal medicine of reinforcing kidney and removing blood stasis on rats with aplastic anemia, and analyzed its effect on secretary of periphery 5-HT.METHODS: Male SD rats were randomized into 4 groups: blank group, model group, TCM (traditional Chinese medicine) group, TCM+ketanserin group (ketanserin 1 mg·kg^-1·d^-1). The peripheral blood of rats in each group were taken at the 0, 7th, 12th, 16th day. The concentration of plasma 5-HT was analyzed by HPLC, at the same time T cell subsets were also analyzed in each group.RESULTS: Pathological changes in bone marrow of TCM group and TCM+ketanserin group were better than the model group, but still worse than the blank group, CD₄⁺ subsets in TCM and TCM+ketanserin group were higher than the model group, but still less than the blank group, CD₈⁺subsets in TCM and TCM+ ketanserin group were less than the model group, but still higher than the blank group, The CD⁴⁺/CD₈⁺ ratio in TCM and TCM+ketanserin group were higher than the model group, but still less than the blank group. HPLC showed that the level of 5-HT of TCM and TCM+ ketanserin group were significant elevated at 12th day compared with the 0, 7th day. The effect of elevation lasts to the 16th day. The group comparison showed that the levels of 5-HT of TCM and TCM+ ketanserin group were higher than the blank control and model group at 12th, 16th day, but the difference of level of 5-HT between the TCM group and the TCM+ketanserin group were not significant at 0, 7th, 12th, 16th day.CONCLUSION: The therapeutic effect of herbal medicine of reinforcing kidney and removing blood stasis can promote the level of 5-HT, at the same time it can improve the function of haematogenesis. The result promotes that the mechanism of the therapeutic effect of herbal medicine of reinforcing kidney and removing blood stasis may have something to do with the promotion of secretion of 5-HT.

Key words: Reinforcing kidney and removing blood stasis, Aplastic anemia, 5-Hydroxytryptamine, High performance liquid chromatogram