AIM:To observe synthesis of CD14 protein and expressionof CD14 mRNA in hepatic tissue and hepatocytes of ratsduring endotoxemia.METHODS:The endotoxemia model of Wistar rat wasestablished by injection of a dose of lipopolysaccharide(LPS)(5mg·kg~(-1),Escherichia coil O111:B4)via the tailvein,then the rats were sacrificed after 3,6,12 and 24 h inbtaches.Hepatocytes were isolated from normal and LPS-injected rats by in situ collagenase perfusion technique andwere collected to measure the expression of CD14 mRNAand synthesis of CD14 protein by reverse transcription-polymerase chain reaction(RT-PCR)or Western blotanalysis.The binding of fluorescein isothiecyanate(FITC)-CD14 polyclonal antibody to isolated hepatocytes was alsoassessed by flow cytometric analysis(FCM).RESULTS:In the rats with endotoxemia,the expressions ofCD14 mRNA in hepatic tissue and isolated hepatocytes werestronger at 3,6,and 12 h than that in control rats(3.48±0.15,5.89±0.62,4.33±0.18,vs 1.35±0.14 in hepatictissue,P<0.01;4.12±0.17,6.24±0.64,4.35±0.18,vs1.87±0.15 in hepatecytss,P<0.01).The synthesis of CD14protein in hepatic tissue and isolated hepatoeytes increasesalso obviously in 6 and 12 h when compared to that incontrol rats(13.27±1.27,17.32±1.35,11.42±1.20,vs 7.34±0.72 in hepatic tissue,P<0.01;14.68±_+1.30,17.95±1.34,11.65±1.19,vs 7.91±0.70 in hepatocytoes,P<0.01).FCM showed that mean fluorescence intensity(MFI)andnumbers of FITC-CD14 positive cells in the rats withendotoxemia increased obviously at 3,6,12 and 24h whencompared with normal control group(43.4%,70.2%,91.4%,32.6% vs4.5%,P<0.01).CONCLUSION:LPS can markedly promote the synthesis ofCD]4 protein and up-regulate the expression of CD14 mRNAin isolated hepatocytes and hepatic tissue.Liver might be amain source for soluble CD14 production duringendotoxemia. AIM: To observe the synthesis of CD14 protein and expression of CD14 mRNA in hepatic tissue and hepatocytes of ratsduring endotoxemia. METHODS: The endotoxemia model of Wistar rat wase established by injection of a dose of lipopolysaccharide (LPS) (5 mg · kg -1, Escherichia coil O111: B4) via the tailvein, then the rats were sacrificed after 3, 6, 12 and 24 h in btaches. Hepatocytes were isolated from normal and LPS-injected rats by in situ collagenase perfusion technique and collected to measure the expression of CD14 mRNA and synthesis of CD14 protein by reverse transcription-polymerase chain reaction (RT-PCR) or Western blot analysis. The binding of fluorescein isothiecyanate (FITC) -CD14 polyclonal antibody to isolated hepatocytes was also assessed by flow cytometric analysis (FCM) .RESULTS: In the rats with endotoxemia, the expressions of CD14 mRNA in hepatic tissue and isolated hepatocytes werestronger at 3,6, and 12 h than that in control rats (3.48 ± 0.15, 5.89 ± 0.62, 4.33 ± 0.18, vs 1.35 ± 0.14 in hepatictissue, P <0.01; 4.12 ± 0.17, 6.24 ± 0.64, 4.35 ± 0.18, vs 1.87 ± 0.15 in hepatecytss, P <0.01). The synthesis of CD14protein in hepatic tissue and isolated hepatoeytes increasesalso obviously in 6 and 12 h when compared to that incontrol rats (13.27 ± 1.27, 17.32 ± 1.35, 11.42 ± 1.20, vs 7.34 ± 0.72 in hepatic tissue, P <0.01; 14.68 ± _ + 1.30, 17.95 ± 1.34, 11.65 ± 1.19, vs 7.91 ± 0.70 in hepatocytoes, P <0.01 ) FCM showed that mean fluorescence intensity (MFI) and numbers of FITC-CD14 positive cells in the rats witheotoxicosis increased obviously at 3,6,12 and 24h whencompared with normal control group (43.4%, 70.2%, 91.4%, 32.6% vs4 .5%, P <0.01) .CONCLUSION: LPS can markedly promote the synthesis ofCD] 4 protein and up-regulate the expression ofCD14 mRNAin isolated hepatocytes and hepatic tissue. Liver might be a source for soluble CD14 production duringendotoxemia.