Department of General Surgery, Capital Institute of Pediatrics, No. 2 Yabaolu Rd., Beijing, 100020, People's Republic of China.
Pediatr Surg Int. 2023 May 6;39(1):192. doi: 10.1007/s00383-023-05480-4.
To investigate the feasibility of the re-patent EHPVO (r-EHPVO) as an animal model of Rex shunt and the effectiveness of Rex shunt in improving abnormal portal hemodynamics and portal venous pathology of EHPVO.
A total of 18 New Zealand white rabbits were randomly divided into three groups: normal control (NC) group, extrahepatic portal venous obstruction (EHPVO) group, and r-EHPVO group. The main portal vein was dissected only in the NC group. The main portal vein was narrowed by a cannula in the EHPVO group. The cannula narrowing the main portal vein was removed to restore the portal blood flow into the liver on day 14 in the r-EHPVO group. The portal pressure, splenic size, blood flow velocity, and diameter of the portal vein were measured on days 14 and 28. The shear stress (SS) and circumferential stress (CS) of the portal vein were calculated. The proximal end of the main portal vein was collected on day 28 for further pathological analysis, and the thickness and area of the intima and media were measured by Image J software. The portal pressure, splenic size, SS, CS, intima and media thickness, the ratio of intimal to medial area (I/M), and the ratio of intimal area to the sum of intimal and medial area (I/I + M) were compared among the three groups. The correlation between SS and intimal thickness and between CS and medial thickness were analyzed.
On day 28, the portal pressure of the EHPVO group was significantly higher than that of the NC and r-EHPVO groups, but no significant difference was detected in the portal pressure between r-EHPVO and NC groups. The length and thickness of the spleen in the EHPVO and r-EHPVO groups were significantly higher than those in the NC group (P < 0.01) but were significantly lower in the r-EHPVO group than those in the EHPVO group (P < 0.05). The SS was significantly lower in the EHPVO group than in NC and r-EHPVO groups (P < 0.05) but was significantly higher in the NC group than in the r-EHPVO group (P = 0.003). The CS was significantly higher in the EHPVO and r-EHPVO groups than that in the NC group (P < 0.05) but was significantly lower in the r-EHPVO group than that in the EHPVO group (P < 0.001). The intimal thickness, I/M, and I/I + M of the EHPVO group were significantly higher than those of the NC and r-EHPVO groups (P < 0.05), but no significant difference was observed between the NC and r-EHPVO groups (P > 0.05). The SS is negatively related to intimal thickness (r = - 0.799, P < 0.001).
The r-EHPVO model is feasible as an animal model of the Rex shunt. The Rex shunt could be beneficial to improving the abnormal portal hemodynamic and portal venous intimal hyperplasia by restoring the portal blood flow into the liver.
研究再发性肝外门静脉高压症（r-EHPVO）作为雷克斯分流术动物模型的可行性，以及雷克斯分流术改善 EHPVO 异常门静脉血流动力学和门静脉病理学的效果。
将 18 只新西兰大白兔随机分为三组：正常对照组（NC）、肝外门静脉阻塞（EHPVO）组和 r-EHPVO 组。仅在 NC 组中解剖主门静脉。EHPVO 组通过套管缩小主门静脉。在 r-EHPVO 组中，在第 14 天移除缩小主门静脉的套管，以恢复门静脉血流进入肝脏。在第 14 天和第 28 天测量门静脉压力、脾脏大小、血流速度和门静脉直径。计算门静脉的剪切力（SS）和周向应力（CS）。在第 28 天收集主门静脉近端进行进一步的病理分析，使用 Image J 软件测量内膜和中膜的厚度和面积。比较三组间门静脉压力、脾脏大小、SS、CS、内膜和中膜厚度、内膜与中膜面积比（I/M）和内膜面积与内膜加中膜面积比（I/I+M）。分析 SS 与内膜厚度之间以及 CS 与中膜厚度之间的相关性。
第 28 天，EHPVO 组的门静脉压力明显高于 NC 和 r-EHPVO 组，但 r-EHPVO 组与 NC 组之间的门静脉压力无显著差异。EHPVO 和 r-EHPVO 组的脾脏长度和厚度明显高于 NC 组（P<0.01），但 r-EHPVO 组明显低于 EHPVO 组（P<0.05）。EHPVO 组的 SS 明显低于 NC 和 r-EHPVO 组（P<0.05），而 NC 组明显高于 r-EHPVO 组（P=0.003）。EHPVO 和 r-EHPVO 组的 CS 明显高于 NC 组（P<0.05），而 r-EHPVO 组明显低于 EHPVO 组（P<0.001）。EHPVO 组的内膜厚度、I/M 和 I/I+M 明显高于 NC 和 r-EHPVO 组（P<0.05），但 NC 和 r-EHPVO 组之间无显著差异（P>0.05）。SS 与内膜厚度呈负相关（r= -0.799，P<0.001）。
r-EHPVO 模型作为雷克斯分流术的动物模型是可行的。雷克斯分流术通过恢复门静脉血流进入肝脏，可能有利于改善异常的门静脉血流动力学和门静脉内膜增生。
