门静脉高压症大鼠联合断流术后胃壁病理变化及意义

目的 探讨门静脉高压症断流术后胃壁的病理变化以及与门静脉高压性胃病之间的关系。方法 用门静脉部分缩窄法制备肝前型门静脉高压症（PHPH）大鼠模型，并设立假手术（SO组）对照；在证实门静脉高压症形成后，两组均予施行联合断流术，分别在断流术后0，3，7，14，30，90d取材；常规病理切片，计算机图像分析胃壁各层厚度及胃壁内血管变化。结果 PHPH组在联合断流术后，胃粘膜下层及肌层厚度先出现下降（P＜0．05），但在3个月后又恢复至术前水平（P＞0．05）。而SO组则无类似变化。PH组随着手术时间的延长，血管腔扩张，血管壁变薄，腔／壁比明显增大（P＜0．05）。结论 门静脉高压症断流术在术后短期内可较明显减少胃的血供，可能与术后早期门静脉高压性胃病的发生有关；而门静脉高压症断流手术后期的出血可能是胃壁静脉曲张、管腔扩张所致。

Significance of pathological changes in stomach wall after devascularization in portal hypertensive rats

Objective To investigate the relationship between portal hypertensive gastropathy and pathological changes in stomach wall after devascularization in portal hypertensive rats. Methods The model of pre hepatic portal hypertension (PHPH) was established in rats by partial vein stenosis. Meanwhile, the model of sham operation (SO) was also established in other rats. Three weeks later, all the rats received devascularization in combination with splenectomy. Furthermore, the lower part of esophagus was transected and reunited. Each of the two groups was divided into 8 sub groups and animals sacrificed in 8 time phases: pre operation, 1, 3, 5, 7, 14, 30 and 90 days after the devascularization in combination with splenectomy, respectively. The pathological changes of the stomach wall were determined and dimension of the layers and blood vessels measured by the computerized pathological image analysis system. Results The dimension of submucosa and muscular layer of the stomach in PHPH rats was markedly decreased in the first month (P<0 05) but gradually increased and returned to the preoperative level 3 months later. However, the SO rats had no similar changes. The dimension of vascular wall in the stomach was significantly decreased while that of the vascular lumen expanded. Therefore, the ratio of vascular lumen dimension to stomach wall dimension was remarkably increased in 3 months after the devascularization (P<0 05). Conclusions The decrease in blood flow of stomach may account for the portal hypertensive gastropathy shortly after devascularization. The regeneration of the stomach varices may result in rebleeding in the late stage after devascularization.