大鼠肝前型门脉高压症形成中门静脉结构的动态变化

Structural changes in the rat portal veins during the pathogenesis ofprehepatic portal hypertension

目的探讨大鼠肝前型门脉高压症形成中门静脉血管结构的动态变化及意义。方法以部分门静脉结扎（PVL）法复制肝前型门脉高压症大鼠模型，采用组织形态学方法及计算机图像分析技术测定PVL术后1、2、4、8、12、16、20、26天大鼠的门静脉内径（ID）、外径（OD）、壁厚（WT）、壁面轵（CSA）及平滑肌含量（SMC），同步监测大鼠门静脉压力（PVP）、门静脉血流量（PVF）、平均动脉压（MAP）、门静脉阻力（PVR）、内赃血管阻力（SVR）等血液动力学参数的动态变化。结果PVL术后，大鼠的PVP、PVR、SVR、MAP发生了显著变化。PVL大鼠门静脉CSA从术后12d起，ID、OD、WT和SMC从术后16d起较对照组显著增加（P〈0．05）。结论门脉高压大鼠存在高动力循环状态（HCS）。HCS可引起门静脉结构变化，其管壁增厚，内外管径增大，平滑肌增生。

AIM To observe the dynamic changes in structure of the rat port alveins during the pathogenesis of prehepatic portal hypertension and investigate the significance. METHODS The models of prehepatic portal hypertension were established in SD rats by means of partial portal vein ligation（PVL）. Such indexes as inner diameter （ID）, outer diameter （OD）, wall thickness （VVT）, cross sectional area （CSA） and smooth muscle content （SMC） in the rat portal veins were studied quantitatively with histological method and computer image analysis in 1,2,4,S, 12, 16,20,26days after PVL. Meanwhile the changes of several hemodynamic indexes such as portal venous pressure （PVP）, portal venous flow （PVF）, mean arterial pressure （MAP）, portal vascular resistance （PVR） and splanchnic vascular resistance （SVR） were detected. RESULTS After PVL, several hemodynamic indexes in rats such as PVP, PVR,SVR and MAP had changed markedly. CSA of the portal vein in rats 12 days after PVL and ID, OD, WT, SMC 16 days after PVL, were much greater than those of corresponding controls （ P 〈 0.05）. CONCLUSIONS The portal hypertensive rats were in hyperdynamic circulatory state （HCS）. Structural changes in the rat portal veins, manifested by thickened vascular wall, increased inner diameter and outer diameter, hyperplasia of the smooth muscle, can be induced bv HCS.