肝硬化大鼠内脏血管组织内皮素及其基因表达的研究

Study on endothlin and its gene expression in Splanchnic vessels in cirrhotic rats

目的探讨肝硬化大鼠内脏血管组织中，内皮素（ＥＴ）及其基因表达量的变化在门静脉高压形成机制中的意义。方法用放射免疫法分别测定大鼠血浆以及门静脉（ＰＶ）和肠系膜上动脉（ＳＭＡ）组织中ＥＴ含量，采用ＲＴ－ＰＣＲ技术分析ＰＶ和ＳＭＡ组织中ＥＴｍＲＮＡ表达量的变化。结果ＰＶ和ＳＭＡ组织中ＥＴ及其ｍＲＮＡ表达量，肝硬化组均显著高于正常对照组（均为Ｐ＜０．００１）；而肝硬化大鼠血管组织ＥＴ含量及ＥＴｍＲＮＡ表达量，则为ＰＶ明显高于ＳＭＡ（＜０．０５），但正常对照组动静脉之间差异无显著性（Ｐ＞００５）。另外，内脏动静脉血管ＥＴ含量之差与门静脉压力呈显著的正相关。结论ＥＴ可能通过更多的收缩内脏静脉特别是门静脉，增加门静脉血流阻力而参与门静脉高压的形成。

Objective To investigate the role of endothlin(ET) in the pathogenesis of portalhnyftension, ET-l level and its gene expression in splanchnic vessels from cirrhotic rats were oberved.Methods ET levels of both plasma and vascular tissues were determined by radioimmunoassay. ET mRNAin vascular tissues was plotal with RT-PCR technique expressed as optical density(OD) value from imageanalysis. Results ET peptide and mRNA in PV and SMA vessels were all significantly higher in cirrhoticrats than those in normal rats, while in cirrhotic rats, ET and its gene expression of PV was dramaticallyhigher than that of SMA(P<0.05). In addition, the positive correlation was oborved in difference betweenPV and SMA in ET concentration with portal pressure(r=0.737, p<0.0l). Conclusion ET may be involved in the machanisms of the formation of PObal hrmrt6nsion mainly due to constructing portal vein,increassing portal flow resistance.