DEPRESSIVE EFFECT OF A TRADITIONAL CHINESE MEDICINE (SHO-SAIKO-TO) ONENDOTOXIN-INDUCED NITRIC-OXIDE FORMATION IN ACTIVATED MURINE MACROPHAGE 5774A.1 CELLS

The present study investigated whether or not Sho-saiko-to (crude powd er extract, TJ-9) can suppress nitric oxide (NO) generation by endotox in-activated J774A.1 cells in order to study the preventive mechanism of Sho-saiko-to against endotoxemia. In this experiment, we estimated the NO2- in the murine macrophage cell line J774A.1 using the Griess m ethod. Our results clearly demonstrated that J774A.1 cells stimulated with endotoxin (0.01-10 mu g/ml) can effectively produce NO, and the p roduction was dependent on the dose of endotoxin. On the other hand, w e investigated the suppressive effect of TJ-9 (10-100 mu g/ml) on NO g eneration by endotoxin (0.1 mu g/ml)-activated J774A.1 cells. The NO l evel when the cells were incubated with endotoxin and TJ-9 (10-20 mu g /ml) was slightly lower than that in cells treated with endotoxin alon e. Tn contrast, treatment with TJ-9 (50-100 mu g/ml) significantly inh ibited endotoxin-activated NO generation in J774A.1 cells, whereas the treatment with TJ-9 (10-100 mu g/ml) alone was ineffective in inducin g NO formation and in inhibiting cell viability in the J774A.1 cells. These findings suggest that a Kampo presciption of Sho-saiko-to shows a suppressive effect on NO generation in macrophages stimulated with e ndotoxin, and that it may be useful in improving endotoxin-shock sympt oms.