脾切除对大鼠血浆及肝肺组织中内毒素廓清的影响

The effect of splenectomy on circulating endotoxin clearance and tissue distribution of endotoxin in rats

目的 观察脾切除对血浆中内毒素清除的影响及内毒素在主要脏器的分布特征 ,探索脾切除后炎症反应与组织损害的发生机制。 方法 雄性Wistar大鼠 112只 ,随机分为有脾组 (n =5 6 ,行大网膜切除术 ,保留脾脏 )、脾切除组 (n =5 6 ,行脾切除术 )。术后 1周静脉注射内毒素 0 1mg/kg,分别于注射前、注射后 10min、0 5、1 5、4、12、2 4h活杀动物 ,测定血浆和肝、肺组织内毒素水平 ,同时检测肝、肺脏器功能指标。 结果 静脉注射内毒素后 10min及 0 5h ,脾切除动物血浆内毒素水平显著高于有脾组 ,显示脾切除大鼠循环内毒素廓清明显延迟。同时 ,脾切除大鼠肝、肺组织内毒素峰值均显著高于有脾组 (P <0 0 5或P <0 0 1) ,2 4h其内毒素水平较基础值仍明显增高 (P <0 0 5 )。无脾组肺组织髓过氧化物酶峰值水平明显高于有脾组 (P <0 0 1)。 结论 脾切除后血浆内毒素廓清能力下降 ,组织中内毒素过量滞留 。

Objective To study the effect of splenectomy on circulating endotoxin clearance and tissue distribution of endotoxin, and investigate the potential mechanism(s) underlying inflammatory response and multiple organ damage following splenectomy.]Methods 112 male Wistar rats were randomly divided into two groups: control group ( n =56, included omentectomy and mobilization of the spleen), and splenectomy group ( n =56). The latter was further sub divided into 10 min, 0 5 ,1 5 , 4 ,12 , 24 hour groups after endotoxin challenge. Tissue and systemic blood endotoxin concentrations were measured using the chromogenic limulus amebocyte lysate (LAL), which was modified by perchloric acid (PCA) pretreatment for samples. Liver function parameter and lung tissue myeloperoxidase (MPO) were also measured. Results After endotoxin administration, plasma endotoxin concentrations were higher in splenectomized rats than in controls at 10 minutes and 0 5 hour ( P <0 01). Endotoxin clearance was delayed in liver and lung in animals after splenectomy. MPO values of the control group were significantly higher than those of splenectomy groups ( P <0 01). ConclusionSplenectomy can lead to impairment of intravascular clearance of endotoxin and endotoxin accumulation in liver and lung. Endotoxin accumulated in local sites may be involved in the development of inflammatory response and multiple organ dysfunction following splenectomy.