The effect of endotoxin tolerance on the expression of chemokine receptor 7 in rats with the acute hepatic failure / 中华急诊医学杂志

ABSTRACT

Objective To study the effect of endotoxin tolerance (ETT) on chemokine receptor 7 (CXCR7) in the liver tissue of rats with acute liver failure (ALF).Methods SD male rats were randomly divided into three groups:normal group,ALF group and ETT group.The rats in the ETT group and ALF group were injected with lipopolysacharide (LPS) 0.1 mg/kg or saline respectively,one time / day for 5 days.At 24 hours after the 5th-day injection,all rats were injected with D-GalN 800 mg/kg and LPS 8μg/rat.Blood sample and liver tissue were collected on 2,6,12,24 and 48 hours after injection.The gene expressions of CXCR7 in the liver were measured by RT-PCR,and the protein expressions of CXCR7 were determined by Western Blot.The data analysis was performed by LSD,Dunnett's t test.Results The histological damage in the liver tissue was significantly mider in ETT group compared to ALF group.The gene expressions of CXCR7 were significantly milder in ETT group compared to ALF group (2 h:F =29.222,6 h:F=166.892,12 h:F=38.975,24h:F=34.603,48 h:F=18.929,allP＜0.01),but still severer than that of normal group.The CXCR7 protein expression in ALF group and ETT group peaked at 24 hours,but the expression of CXCR7 in ETT group was lower compared with that in in ALF group (2h:F=11.155,6 h:F=42.553,12h:F=17.082,all P＜0.01; 24 h:F=7.242,P＜0.05).Conclusions During the process of endotoxin tolerance,LPS pretreatment and D-GalN can decrease the liver injury,down-regulate the expressions of CXCR7mRNA and CXCR7.This suggests that CXCR7 may play an important role in the ETT.