脑水肿的发病机理及药物治疗.pptxVIP

脑水肿的发病机理及药物治疗 医院及讲者信息 脑水肿 脑实质聚集过量液体 脑水肿分类 血管源性脑水肿 血脑屏障受损所致，大量液体和血管内蛋白质积聚于脑白质细胞间隙 常见于脑创伤、脑出血、脑缺血的第二阶段 脑水肿分类 细胞毒性脑水肿 ATP失功、细胞内外Na+转运失衡所致 水肿液分布于脑细胞内，细胞间隙不但不扩大，反而缩小 常见于脑缺血和肝衰 脑水肿动物实验模型 冻伤模型 液压冲击伤模型 脑出血模型 水中毒模型 肝损模型 The Cold Injury Model 冻伤模型 主要用于血管源性脑水肿的试验模型 冻伤直接破坏血管细胞，导致不可逆的血脑屏障损伤 特点：试验的可重复性及受伤面积的准确性 The Fluid Percussion Injury (FPI) Model Fluid percussion injury is performed by an injury to the intact dura after craniectomy by impacts of rapidly pushed fluid (B1,B2). As well as cold injury, the extravasation of Evans blue dye is observed (B3). 液压冲击伤模型 模拟脑创伤引发的脑水肿 可诱导各种降解酶如MMP-9的激活，导致血管基底膜的降解 可观察到炎性介质的增加及巨噬细胞的浸润； The Cerebral Hemorrhage Model 通过脑实质内注射胶原蛋白酶破坏血管基底膜或者注射自体血制备脑出血模型（ICH model） 常见的蛛网膜下腔出血模型（SAH model）包括：单侧出血、双侧出血、血管内穿刺模型 可同时观察到血管源性脑水肿及细胞毒性脑水肿 The Water Intoxication Model induces a relative decrease of extracellular Na+ concentration， best reflects simulation of hyponatremia produced by intraperitoneal loading of excessive distilled water corresponding to 10%–40% of the body weight of experimental animals adopted as a model of cytotoxic edema. The Liver Failure Model 急性或慢性肝细胞失功引发的肝衰会诱导肝性脑病，造成中枢神经组织严重失功。 急、慢性肝衰导致的脑水肿发病机制不同 急性肝衰，ICP上升；慢性肝衰很少观察到ICP上升 肝衰模型产生的脑水肿为细胞毒性脑水肿 星形细胞肿胀 血脑屏障未见损害 一般采用硫代乙酰胺诱导肝细胞损伤 氨基半乳糖诱导急性肝衰 胆管结扎或门腔静脉吻合术诱导慢性肝衰 评估脑水肿方法 干湿称重法 重量法 MRI检测法 Wet-Dry Weight Method a common and simple method invasive and not performed in patients based on the weight measurement of brain tissue before and after complete dehydration Water content (%) = 100× (wet weight − dry weight) /wet weight Water content = (wet weight − dry weight)/dry weight Tissue swelling (%) = 100× (final wet weight − initial wet weight) /initial wet weight wet weight：The weight before dehydration dry weight：the weight after dehydration The Gravimetric Method The gravimetric technique is based on calculating the percentage of water from measuring the density of the tissue in experimental animals This method is also invasive and not performed in patients Advantages: higher sensitivity use of s