[Effect of nitric oxide on NF-kappaB activation induced by cigarette smoke extract in rat alveolar macrophage].
OBJECTIVE
To explore the effect of nitric oxide on NF-kappaB activation in rat alveolar macrophage(AM) induced by cigarette smoke extract(CSE) and the involved mechanism.


METHODS
AMs were co-cultured with NO precursor L-arginine (L-Arg) or inhibitor of inducible nitric oxide synthase L-N(6)(1-iminoethyl)lysine (L-NIL) and CSE. The expression of NF-kappaB was determined by immunocytochemistrical staining, the content of I-kappaB protein was detected by Western blot, the level of NO in supernatant was assayed by Griess reaction.


RESULTS
CSE could induce NF-kappaB activation and decrease level of I-kappaB. L-Arg augmented CSE-induced NF-kappaB activation and decreased I-kappaB content at low concentration while inhibited CSE-induced NF-kappaB activation at high concentration, but there was not any significant difference of the expression of I-kappaB. The percentage of NF-kappaB nucleus dyeing positive cells was lower and the expression of I-kappaB was higher in response to CSE plus various concentrations of L-NIL as compared with that in response to CSE alone (P<0.01). The changes induced by L-NIL were concentration-dependent.


CONCLUSIONS
NO may up-regulate and down-regulate the activation of NF-kappaB induced by CSE according to difference in NO concentration in AMs.
Yang
Dan-lei
DL
Department of Respiratory Medicine, Tongji Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, China. yangdanlei@yahoo.com
Xu
Yong-jian
YJ
Zhang
Zhen-xiang
ZX
Li
Chao-qian
CQ
D000818:Animals; D001120:Arginine / Q000494:pharmacology; D020672:I-kappa B Proteins / Q000378:metabolism*; D008168:Lung / Q000166:cytology; D008239:Lysine / Q000031:analogs & derivatives / Q000494:pharmacology; D016676:Macrophages, Alveolar / Q000378:metabolism*; D008297:Male; D016328:NF-kappa B / Q000378:metabolism*; D009569:Nitric Oxide / Q000494:pharmacology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D051381:Rats; D017208:Rats, Wistar; D012906:Smoke / Q000009:adverse effects*; D014026:Nicotiana
D020672:I-kappa B Proteins; C090663:N(6)-(1-iminoethyl)lysine; D016328:NF-kappa B; D012906:Smoke; D009569:Nitric Oxide; D001120:Arginine; D019001:Nitric Oxide Synthase; D008239:Lysine