P物质及其受体在小鼠免疫性肝炎中的作用

Effects of substance P and its receptor in hepatic immune injury induced by Concanavalin A in mice

目的观察P物质(SP)及其受体NK-1R介导的神经源性炎症在小鼠免疫性肝炎发病中的作用和可能机制。方法小鼠尾静脉注射刀豆蛋白A(Con A)建立免疫性肝炎模型组,注射生理盐水作为对照组。HE染色观察肝脏病理变化;肝组织匀浆SP测定采用酶联免疫吸附(ELISA)法;同时应用RT-PCR法对各组动物肝脏组织中NK-1Rm-RNA的表达水平进行相对定量比较。结果模型组肝脏损害严重,以肝细胞肿胀和免疫细胞浸润为特征;肝组织匀浆SP含量模型组(507.25±30.35)显著高于对照组(238.59±21.90)(P<0.01);而且模型组NK-1R mRNA的表达显著上调(P<0.05)。结论P物质及其受体参与了小鼠免疫性肝炎的起始阶段,并在炎症的激发和扩大方面发挥了重要作用。

Objective To investigate the role of substance P and neurogenic inflammation mediated by SP in hepatic immune injury induced by concanavalin A（ Con A）. Methods Hepatic immune injury in mice was established by injection with 20 mg/kg Con A through the tail vein. A saline control group was established by injection with saline. Liver damage was assessed by histological evaluation; SP contents in liver homogenates of the two groups were determined by enzyme-linked immunosorbent assay （ELISA）, and neurekinin-1 receptor expression was detemfined by reverse transcription and PCR（RT-PCR）. Results Hepatic immune injury in mice was successfully established, and hepatocellular apoptosis and granulocyte infiltration were found in livers in the model group. SP contents in liver homogenates were significantly increased in the model group（ P 〈 0. 01 ）. Moreover, NK-1R mRNA expression in the model group was obviously higher than that in the control group （ P 〈 0.05）. Conclusion SP and its receptor participate in the process of inflammatory liver injury induced by Con A and play an important role in induction and maintenance of inflammation.