Mechanisms Of The NF-κB Activation Of Kupffer Cells On Liver Injury

Objective: To investigate the time-course characteristic of nuclear factors kappa B(NF- κ. B) activation in cultured liver Kupffer cells(KCs) with rat recombination tumor necrsis factor alpha(rTNF α ) stimulated and to explore the orderliness different dosages of rat rTNF α affected on their NF- K B activation, to observe dexamethasone(Dex) influences on the activation of NF-κ B and the secretion of TNF α modulated by NF- K B, then to defmitude the effects of NF- K B activation on liver injury.Methods: We applied in site perfusion to isolate Spraqae-Dawley rat, obtained liver non-parenchymal cells(NPCs) with diversity centrifugal force(CF), utilized discontinuous density gradient and selectively adherence to isolate KCs, they were deposited in -80℃. KCs were divided into different groups and subgroups which cells are nearly 0.5-1.0X 107/ml, including control group, the groups were stimulated by 1 0ng/ml rat rTNF a were tested the NF- K B activation according to time course, namely 0,0.5 hour,l hour,2 hours,4 hours, 6 hours,8 hours, in 2 hours, the groups stimulated with different rat rTNF α doses ,namely 0 ng/ml, 5 ng/ml, 10 ng/ml, 20 ng/ml, 50ng/ml, l00ng/ml, we collected KCs to abstract nuclear ,then to test NF- K B activation with ELISA kits, TNF α density were tested with TNF α ELISA kits in theMchanisms of the NF- x. B activation of Kupffer Cells on liver injury Abstractgroups l0ng/ml rat rTNF a stimulated and the group 2mg/L Dex treated. Results: We obtained NPCs 233.094.53 X 106 per gramme liver through initial centrifugation, after discontinuous density gradient, we obtained NPCs 40.033.56 X 106 per gramme liver, and through selectively adherence we obtained KCs 30.83 3.24 X 106 , the purity is 95.5%, the survival rate is 94.85%. In the groups 10 ng/ml rTNF a treated , the NF- K B activation gradually increased, their peak appears in 2 hours, then gradually descended to nearly normal level, in 8 hours(p>0.05), the others are significant difference(p<0.001), the NF- K. B "activation increased following the density of rTNF a (p<0.001), both the density of TNF a and NF- K B activation descended in the groups treated with Dex, comparison with the groups treated with rTNF a shows significant difference(p<0.001).Conclusions: rTNF a can increase the NF- K B activation, its characteristics are dosage-dependent, the peak appears in 2 hours, the time course modulation of NF- K B activation might be a early event, Dex can inhibit the NF- K B activation of KCs and modulate the secretion of core cytokine.