• Archives of Pharmacal Research
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• v.18 no.4
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• pp.262-266
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• 1995

Bacterial lipopolysaccharide (LPS) is one of the most potent inducers of various cytokines nad other proinflammatory mediators in macrophages. Although pathophysiological consequences of LPS-induced responses are well established, the mechanisms through which LPS-generated singals are transduced remain unclear. In the present study, we attempted to determine early intracellular events after LPS binding which transduced the signal for the induction of arachidonic acid metabolism in rat alveolar macrophages. While H-7, a protein kinase C(PKC) inhibitor, did not affect LPS-stimulated prostaglandin synthesis, staurosporine enhanced archidonic acid etabolism in macropahages treated with LPS. Phorbol-12-myristate-13 acetate snesitive to LPS compare with control group. PMA and H-7 did not alter the effect of flucose. Pertussis toxin did not show nay effect, thus pertussis toxin snesitive G-protein pathway appears not to play a role in this experimental system. Genistein and tyrphostin 25, protein tyrosine kinase 9PTK) inhibitors, markedly inhibited prostaglandin synthesis in macrophages nal transduction events leading to icnreased macrophage arachidonic acid metabolism.

• The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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• v.15 no.2
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• pp.1-19
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• 2002

Fifteen herbs used in oral medicine were extracted in ethanol and screened for tooth whitening effect, radical scavenging activity, inhibition of inducible nitric oxide synthase activity and anti-bacterial activity on Streptoccocus mutans. The results are as followed: 1. The tooth whitening effect of toothpaste containing 1 $\%$ ethanol extracts of 15 herbs was tested in brushing method using artificially stained HAT tablet and bovine tooth specimens. Toothpaste containing 1$\%$ of Vucia unijuga, Illicium verum, Angelica dahurica and Piper longum extracts showed tooth whitening effects on both HAT tablet and bovine tooth specimens. But the others did not show a considerable activity. 2. The antioxidant activity of ethanol extracts of 15 herbs was tested using the method of 1,1-diphenyl-2-picryl hydrazyl (DPPH) reactivity. Two ethanol extracts of Cimicifuga heracleifolia and Phyllostachys nigra var. henonis were found to be the most effective on radical scavenging activity. C. heracleifolia and P. nigra var. henonis extracts removed 86$\%$ and 81 $\%$ of DPPH radical at 0.01$\%$, compared with butylated hydroxy toluene as positive control. 3. The inhibition activity of ethanol extracts on nitrate production In RAW264.7 cell stimulated by lipopolysacchride was tested using the Griess reagent. But all extracts did not inhibit nitrate production. 4. The antibacterial activity on Streptoccocus mutans was tested by paper disk method. But no one extract showed any anti - bacterial activity.

• Journal of Yeungnam Medical Science
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• v.14 no.2
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• pp.337-349
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• 1997

This study was undertaken to examine the intensity of involvement of inducible nitric oxide synthase (iNOS) and cyclic GMP signal transduction pathway as one of the mechanisms of vaso-relaxative action of bacterial lipopolysaccharide (LPS) on the canine femoral artery strips. Canine femoral arteries were isolated and spiral strips of 10 mm long and 2 mm wide were made in the Tyrode solution of $0-4^{\circ}C$. The strips were prepared for isometric myography in Biancani's isolated muscle chamber containing 1 ml of Tyrode solution, which was maintained with pH 7.4 by aeration with 95% $O_2$/5% $CO_2$ at $37^{\circ}C$ and nitric oxide (NO) production was measured simulltaneously with isolated nitric oxide meter. LPS induced NO production, suppressed the phenylephrine (PE) induced contraction and enhanced the acetylcholine (ACh) induced relaxation. $N^G$-nitro-L-arginine methyl ester (L-NAME), an NOS inhibitor, methylene blue, a guanylyl cyclase inhibitor, potentiated PE induced contraction and suppressed ACh induced relaxation on the LPS treated strips. The inhibitory potency of methylene blue for LPS induced vascular hyporesponsiveness was stronger than that of L-NAME. These results suggest that in canine femoral artery, both iNOS and cyclic GMP signal trnasduction pathway are related with LPS induced vascular hyporeponsiveness, but in minor with iNOS and in major with cyclic GMP signal trnasduction pathway.