BNL·CL2 세포에서 간절제 후 혈청에 의한 유도성 Nitric Oxide Synthase 유전자의 전사 활성화에 관한 연구 = Regulation of Inducible Nitric Oxide Synthase by Serum After Partial Hepatectomy in BNL·CL2 Murine Liver Cells

다국어 초록 (Multilingual Abstract)

An activation of transcription factors involved in the transactivation of inducible nitric oxide synthase (iNOS) gene occurred after partial hepatectomy (PH), resulting in the transient expression of iNOS. The effect of serum after PH on iNOS gene expression has been investigated with RT-PCR, elctrophoretic mobility shift assay (EMSA) and chloramphenicol acetyltransferase (CAT) assay.
Stimulation of iNOS mRNA expression reached a maximum with serum from 3 h and 5 h of PH. This stimulation was preceded by an early and transient activation of NF-κB complex composed of p50/p65 heterodimer, which was rapidly activated with serum from 1 h and 3 h of PH, and tend to decline with serum after 5 h of PH. The stimulatory effects of serum after PH were does-dependently inhibited by treatment of PDTC. Transfection of BNL-CL2 cells with iNOS promoter linked to a CAT reporter gene was followed by stimulation with serum after PH. Site-specific mutation of three conserved nucleotide within the upstream NF-κB site showed no difference in CAT activity by serum after PH compared with that of cells transfected with wild type iNOS promoter. In contrast, site-specific mutation of the downstream NF-κB caused remarkable reduction in the reporter gene expression by serum after PH.
These results suggest that serum after PH regulates the iNOS gene transcription via NF-κB complex (p50/p65 heterodimer) activation, and downstream NF-κB site is the essential component in transcription of iNOS gene during hepatic regeneration.