改良“二次注血法”建立蛛网膜下腔出血后迟发型血管痉挛模型

Establishment of modified ＂double injection of blood＂ subarachnoid hemorrhage induced delayedcerebral vasospasm model in rats

目的应用改良＂枕大池二次注血法＂建立稳定、可靠的蛛网膜下腔出血（SAH）模型，并评估其脑血管痉挛程度。 方法在＂枕大池二次注血法＂的基础上进行改良：（1）利用立体定向仪在三维空间定位和角度调节，更加准确地穿刺枕大池的部位。（2）应用微量注射泵以恒量、恒速注射自体血，减少手工注射时对脑干的损伤。采用随机数字法将SD大鼠分为：假手术组、对照组、SAH组，每组各25只。SAH组采用改良＂枕大池二次注血法＂建立蛛网膜下腔出血模型，对照组用等量的生理盐水，假手术组仅仅暴露寰枕筋膜。观察该模型的成功率和失败率、神经功能、脑组织含水量、基底动脉改变、局部脑血流量（rCBF）变化。 结果与假手术组比较，SAH组大鼠造模第1天时神经功能受损严重，差异有统计学意义[（9.2±0.7）分比（1.0±0.6）分，P＝0.001]；与假手术组、对照组比较，SAH组第1天时大鼠脑组织含水量显著增多，差异有统计学意义[（79.98±0.11）%比（78.29±0.12）%、（78.39±0.13）%，P＝0.001]。光镜下苏木素-伊红（HE）染色结果显示：与假手术组比较，SAH组第5天时大鼠基底动脉管腔内径和管腔面积明显缩小，差异有统计学意义[（325.200±15.156） μm比（461.000±22.705） μm，P＝0.000；（80 739.200±7 297.735） μm2比（167 124.200±7 067.155） μm2，P＝0.000]。激光散斑结果显示：SAH组大鼠第5天时的rCBF明显低于假手术组和对照组，差异有统计学意义[（56.0±3.5）%比（97.2±1.7）%、（95.8±3.5）%，P＝0.001]。 结论应用改良＂枕大池二次注血法＂可以建立稳定、可靠的SAH模型。

ObjectiveThe subarachnoid hemorrhage （SAH） models were established by modified double injection of autologous blood into the rat cisterna magna and then assess the degree of delayed cerebral vasospasm. MethodsThe details of improved ＂double injection of autologous blood model＂ is as folllows： （1） Stereotaxic apparatus was used to located the cisterna magna in the three-dimensional space. （2） Instead of manual injection, the micro-injection pump, which keep the volume and injection speed constant, was used. A total of 75 male SD rats were included in this study and randomly divided into the following three groups （n=25/group）： sham group, control group and SAH group. SAH group, rats subjected to double injection of autologous blood into the cisterna magna; control group, rats subjected to double injection of the equal quantity saline; sham group, rats subjected to only explosion of atlanto-occipital membrane. The success rate and failure rate, neurological function, brain water content, changes of basilar artery, regional cerebral blood flow （rCBF） were observed. ResultsNeurological function in SAH group were significantly impaired as compared with sham group at day 1 （9.2±0.7 vs. 1.0±0.6, P=0.001）. Brain water contents in SAH group were significantly increased as compared with sham group and control group at day1 [（79.98±0.11）% vs. （78.29±0.12）%, （78.39±0.13）%, P=0.001]. Hematoxylin and eosin （HE） staining results showed a significant reduce of basilar artery lumen diameter and area in SAH group than that in sham group at day5 [（325.200±15.156） μm vs. （461.000±22.705） μm, P=0.000; （80 739.200±7 297.735） μm2 vs. （167 124.200±7 067.155） μm2,P=0.000]. The result of rCBF of SAH group, measured by Laser speckle, also showed a significant decrease compared to sham group at day5 after SAH [（56.0±3.5）% vs. （97.2±1.7）%, （95.8±3.5）%, P=0.001]. ConclusionThe stable and reliable subarachnoid hemorrhage model can be established by modified double injection of autologous blood into the cisterna magna.