门静脉主干缩窄法制备SD大鼠门静脉高压症模型时最佳口径的探讨

目的 探讨缩窄门静脉主干法制备SD大鼠门静脉高压症模型时的最佳缩窄口径.方法 SD大鼠70只,随机分为正常组和6个实验组,每组各10只.正常组行假手术.各实验组分别按照5、6、7、8、9、12号针头的缩窄口径行门静脉主干缩窄术.观察各组大鼠术后累积死亡率,术后状态,术前、术后即刻及术后2周时的门静脉压力,术后2周时的食管组织学变化和脾指数.结果 5、6、7、8、9、12号针头缩窄组术后3 d时大鼠的累积死亡率分别为100%、80%、70%、20%、10%、0%,与缩窄程度正相关.8、9、12号组的大鼠存活状态明显好于5、6、7号组.5、6、7、8、9、12号组术后即刻门静脉压力分别为:(5.836±0.275)、(4.557±0.419)、(3.856±0.576)、(3.343±0.433)、(2.708±0.309)、(1.957±0.358)kPa,7、8、9、12号组术后2周时门静脉压力分别为:(2.163±0.424)、(1.956±0.172)、(1.841±0.202)、(1.232±0.154)kPa,均较正常(0.881±0.165)kPa显著升高(P＜0.05).术后2周,7、8、9、12号组大鼠食管下段黏膜下层平均血管数目分别为:(3.94±0.83)、(3.58±0.63)、(3.14±0.64)、(2.02±0.62)个,与正常组(1.65±0.62)个比较,除12号组外均有增多(P＜0.01);固有层平均血管数目分别为:(2.24±0.64)、(2.05±0.29)、(1.52±0.28)、(0.93±0.19)个,与正常组(0.82±0.18)比较,除第12组外均增多(P＜0.01);黏膜下层血管口径分别为:(4.52±1.51)、(4.05±1.23)、(3.75±1.11)、(2.03±0.86)μm,除第12组外均增大(P＜0.01);脾指数分别为:(4.21±0.93)、(4.06±0.68)、(3.84 4±0.71)、(3.31±0.69)除12号组外也较正常增加(P＜0.01).结论 缩窄门静脉主干可成功制成大鼠门静脉高压症模型;其最佳缩窄口径应该是:大鼠体重200 g左右时用8号针头(直径0.8mm),大鼠体重300 g左右时用9号针头(直径0.9 mm).

The best degree of partial portal vein ligation in making a rat model of pre-hepatic portal hypertension

Objective To explore the best degree of portal vein stenosis in making a pre-hepatic portal hypertension rat model by partial portal vein iigation.Methods Seventy Sprague-Dawhy rats were randomly divided into one control group(sham operation)and 6 experimental groups(n=10 in each group).The 6 experimental groups were named No.5,No.6,No.7,No.8,No.9 and No.12 group respectively according to the dimeter of portal vein being constricted at the needles' diameter(0.5,0.6,0.7,0.8.0.9 and 1.2mm respectively).Following indexes were observed in all groups:The cumulative mortality;spleen index at 2nd post operation;portal vein pressure;average number and diameter of blood vessels in the inferior segment of esophagus before and 0 and 2 weeks after operationResults After portal vein stenosis in different diameter,the cumulative mortality rate of 6 experimental groups was 100%,80%,70%,20%,10%,0 respectively.The post-operative mortality had a positive correlation with the degree of portal vein stenosis.The postoperative condition of the animals in No.8.No.9 and No.12 groups were much better than that in No.5,No.6 and No.7 groups.The portal pressure in 6 experimental groups [(5.836±0.275),(4.557±0.419),(3.856±0.576),(3.343±0.433),(2.708±0.309),(1.957±0.358)kPa]was increased significantly(P＜0.05)immediately after operation instantly,and in No.7,No.8,No.9 and No.9 group,the portal pressure[(2.163±0.424),(1.956±0.172),(1.841±0.202),(1.232±0.154)kPa]was increased significantly(P＜0.05)at 2nd week after operation.In No.7,No.8 and No.9 groups,the average number and diameter of blood vessels in the inferior segment of esophagus were increased as compared with control group(P＜0.01)blood vessel number:(3.94±0.83),(3.58±0.63),(3.14±0.64);blood vessel diameter:(4.52±1.51),(4.05±1.23),(3.75±1.11)μm].The spleen index in No.7,No.8,No.9 and No.12 groups[(4.21±0.93),(4.06±0.68),(3.84±0.71),(3.31±0.69)]was increased(P＜0.05 or P＜0.01).Conclusion Portal vein stenosis could make rat portal hypertension model'suecessfully.The optimal caliber(diameter)for portal vein stenosis was as follows:8 mm in rats weighing 200 g,and 9 mm in those weighing 300 g.