[Studies on the antitumor activity of traditional Chinese medicines. (II). The antitumor mechanism of traditional Chinese medicines].

Either i.p. or p.o. administration of Zhu-Ling-Tang, Xiao-Chai-Hu-Tang, Shi-Quan-Da-Bu-Tang and Ren-Shen-Tang enhanced the function of the reticuloendothelial system (RES) in mice. The relative organ weights of thymus, spleen and liver were increased as compared with the control. Furthermore, binding of C3 cleavage product (C3b) to peritoneal macrophages after p.o. administration of Xiao-Chai-Hu-Tang was enhanced as shown by fluorescent antibody technique. In conclusion, it was considered that one of the mechanisms of the antitumor activities of theses drugs was the stimulation of a host-mediated factor such as the phagocytic function of the RES and C3 cleavage producibility.