쥐에서의 백작약에 의한 iNOS 발현 조절

초록

Nitric oxide(NO) is a small ubiquitous molecule influencing a great variety of biological process in the organism. Within the immune system, increased levels of NO were observed in various immumopathological situations such as inflammatory reactions. Our previous studies have shown that oral administration of Paeonia japonica(PJ) water extract may modulate immune function by regulating the cytokine production of mouse peritoneal macrophage stimulated with lipopolysaccharides(LPS). In the present study, we investigated the effects of PJ water extract on the production of Nitric oxide(NO) and on the level of inducible Nitric oxide synthase(iNOS) gene expression in mouse peritoneal macrophages. The PJ water extract was administered every other day for two or four weeks. Peritoneal macrophages of PJ-treated mice were incubated for 4 to 24hrs with/without LPS to induce iNOS expression. The accumulation of nitric was measured by Griess assay. The level of mRNA and protein of iNOS were determined by RT-PCR and western blot analysis, respectively. Nitric production was increased in PJ treatment group when incubated with LPS. The intensity of the iNOS mRNA and protein expression was increased after 4hrs of incubation and a strong band was observed at 8hrs incubation in LPS-treated groups. However, iNOS was not expressed at all without LPS treatment. The results suggest that PJ may regulate the immune function by enhancing the response to endotoxin stimulation. .