Journal of Yeungnam Medical Science

Original Articles

Upregulation of IP-10(CXCL10) mRNA Expression by Interleukin-18.: Hyo Young Kim, Hee Sun Kim; Yeungnam Univ J Med. 2007;24(1):67-78. Published online June 30, 2007; DOI: https://doi.org/10.12701/yujm.2007.24.1.67

Abstract PDF: BACKGROUND
Interleukin-18 (IL-18) is one of the principal inducers of interferon-gamma (IFN-gamma) in lymphocytes. MATERIALS AND METHODS: The effect of IL-18 on the expression of chemokine IP-10(CXCL10) mRNA in C57BL/6 mouse peritoneal macrophages was studied by using Northern blot analysis, enzyme linked immunosobent assay and electrophoretic mobility shift assay. RESULTS: IL-18 was determined to exert no direct effect on the expression of IP-10(CXCL10) mRNA. However, IL-18 pretreatment was determined to play a cooperative role in the synergistic induction of LPS-induced IP-10(CXCL10) mRNA expression. The effect associated with IL-18 pretreatment with regard to the synergistic induction of LPS-induced IP-10 (CXCL10) mRNA expression was detected after 16 hr of IL-18 pretreatment, administered prior to LPS stimulation. The pattern of NF-kB binding activity during IL-18 pretreatment with LPS stimulation was found to coincide with the expression of IP-10(CXCL10) mRNA. CONCLUSION: Although IL-18 alone exerts no direct effect on the expression of chemokine IP-10(CXCL10), a definite period of IL-18 pretreatment induces the synergistic expression of LPS-induced IP-10(CXCL10) mRNA. NF-kB activation is a component of this synergistic effect of IL-18 pretreatment. These results provide useful information, which may facilitate the elucidation of the action mechanisms underlying IL-18 effect on the expression of IP-10(CXCL10) mRNA.

Effect of NG-nitro-L-arginine methyl ester and Methylene Blue on the Endotoxin-induced Vascular Hyporesponsiveness.: Hyoung Chul Choi, Jeoung Hee Ha, Kwang Youn Lee, Won Joon Kim, Uy Dong Sohn; Yeungnam Univ J Med. 1997;14(2):337-349. Published online December 31, 1997; DOI: https://doi.org/10.12701/yujm.1997.14.2.337

Abstract PDF: The 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 Tyroad solution of 0-4degrees C. The strips were prepared for isometric myography in Biancani's isolated muscle chamber contaning 1 ml of Tyrode solution, which was maintained with pH 7.4 by areation with 95% O2/5% CO2 at 37degrees C and nitric oxide (NO) production was measured simulltaneously with isolated nitric oxide mrter. LPS induced NO production, suppressed the phenylephrine (PE) induced contraction and enhanced the acetylcholine (ACh) induced relaxation. NG-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 hyporeponsiveness was stronger than that of L-NAME. These result suggest that in canine femoral artery, both iNOS and cyclic GMP signal transduction pathway are related with LPS indused vascular hyporeponsiveness, but in minor with iNOS and in major with cyclic GMP signal transduction pathway.

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