【作者】 金钊；

【导师】 李卫平；

【作者基本信息】 大连医科大学 ， 药理学， 2007， 硕士

【摘要】 目的临床上,急性脑血管病伴多器官功能障碍综合征(multiple organ dysfunction syndrome,MODS)是造成此类患者死亡的重要病因。寻找有效的治疗药物并探索其可能的作用机制成为当前基础和临床研究迫切要解决的重点问题。本课题所研究的茶多酚(tea polyphenol,TP)是从天然植物茶叶中分离提纯的多酚类化合物。既往研究已证实,TP对不同模型的动物脑缺血/再灌注性损伤有肯定的对抗作用。本实验旨在研究茶多酚对于由脑缺血再灌注损伤引起的MODS的保护作用,并进一步探讨其保护机制。方法健康雄性SD大鼠,体重220±20g,随机分为假手术组,模型组,TP100mg﹒kg-1组(TP100),TP50mg﹒kg-1组(TP50)以及阳性药Nimodipine组(Nim)。采用改良的四动脉阻断15min,再灌注3h制备大鼠全脑缺血再灌注损伤模型。以脑、肺、肠组织形态,脑含水量,脑组织和肺组织中热休克蛋白70(HSP70)表达等指标,反映组织损伤情况及TP干预结果。结果1. TP对于大鼠全脑完全缺血再灌注损伤后脑、肺、肠组织形态学变化的影响:1.1对于脑组织形态学变化的影响:假手术组HE染色镜下观察神经细胞层次清晰,细胞大小、形态、周围间隙均正常。模型组以及各给药组均有不同程度的细胞肿大,神经细胞成片状坏死,残留坏死吸收后形成空泡。神经细胞呈三角形,胞浆及核深染,核固缩或溶解,细胞周围间隙膨胀,间质水肿呈松散网状。TP组的细胞肿胀程度,间质空隙,胞核等变化均较模型组轻。1.2对于肺组织形态学变化的影响:假手术组肺组织石蜡切片、HE染色,镜下观察无明显病理变化。模型组可见毛细血管扩张充血。肺泡结构紊乱,壁增厚,大量炎性细胞浸润,肺泡腔内有红细胞渗出,亦可见大量白细胞浸润及脱落上皮细胞。TP组病变程度均较模型组明显减轻。1.3回肠组织形态学变化:假手术组肠壁绒毛形态完整,绒毛表面的吸收细胞呈高柱状,固有膜层可见纤维组织之间散在淋巴细胞、浆细胞,粘膜下层和肌层无水肿及纤维化。模型组肠壁绒毛大量破损、消失,固有膜层有红细胞,可见细胞脱落,基层变薄。TP给药组损伤较模型组明显轻微。2. TP对于大鼠弥散性全脑完全缺血再灌注损伤后脑组织含水量的影响:模型组大鼠脑组织含水量[(78.8±0.6)%]明显高于假手术组[(75.6±0.8)%]。与模型组相比, TP50组、TP100组、阳性药Nim组脑组织含水量分别为([76.5±2.9)%、(77.2±0.9)%、(76.9±1.0)%],均有显著降低(P<0.01),而与假手术组比较差异不明显(P>0.05)。3. TP对于大鼠弥散性全脑完全缺血再灌注损伤后脑组织中HSP70阳性表达率的影响:与假手术组[(3.7±3.9)%]相比,模型组[(54.6±14.1)%] HSP70阳性表达率明显升高(P<0.01)。与模型组[(54.6±14.1)%]相比, TP50mg/kg组[(36.9±9.8)%]、TP100mg/kg组[(19.5±9.8)%]、阳性药组Nim200mg/kg[(34.9±7.3)%]均显著降低HSP70阳性表达率(P<0.01)。TP组之间比较,TP50组[(36.9±9.8)%]、TP100组[(19.5±9.8)%]之间有显著性差异(P<0.01),反映剂量依赖关系。4. TP对于大鼠弥散性全脑完全缺血再灌注损伤后肺组织中HSP70阳性表达率的影响:与假手术组[(1.4±0.3)%]相比,模型组[(39.2±7.9)%] HSP70阳性表达率明显升高(P<0.01)。与模型组[(39.2±7.9)%]相比, TP50组[(13.6±10.4)%]、TP100组[(4.2±0.3)%]、阳性药组Nim200 [(3.4±0.9)%]均显著降低HSP70阳性表达率(P<0.01)。TP组之间比较,TP50组[(13.6±10.4)%]、TP100组[(4.2±0.3)%]之间有显著性差异(P<0.01),反映剂量依赖关系。结论全脑缺血再灌注可引起脑组织损伤,并伴发肺、肠组织损伤,发生多器官功能障碍(MODS)。TP静脉注射给药可明显减轻上述损伤,机制与其降低机体应激反应有关。更多还原

【Abstract】 AIM Due to high fatality rate and complex mechanisms, multiple organ dysfunction syndrome (MODS) is receiving increasing attention. Meanwhile, MODS is also a serious complication. Recently, MODS caused by brain injured has become the focus of research. The tea polyphenol (TP) belongs to phenolic compounds purified from tea leaves. The purpose of this thesis is to study the protective and TP actions of TP in MODS, which caused by cerebral ischemic reperfusion injury, further discussing its protective mechanisms.METHODS Adult male SD rats, of which the weight is 220±20g, were divided into 5 groups at random, and the 5 groups contained sham operation, model, TP50, TP100, and nimodipine control. The experiment adopted the improved blocking four arteries, that is, bilateral arteria carotis communis and bilateral arteria vertebralis, and to build the model of cerebral ischemic reperfusion injury(blocking 15min then reperfusion for 1h). Adm of TP was intravenous injection. Some indexes were observed, including the influence of TP with different doses on changes of water content in brain, the histomorphology of brain, lung and intestine. What is more, immunohistochemical indexes including HSP70 in brain tissue and HSP70 in lung tissue were observed as well.RESULTS1. The influence of TP on the changes of histomorphology in the model of cerebral ischemic reperfusion injury:1.1. Observed brain tissue by the microscope, sham operation , had clear cell layers, normal shape and gaps in cellular nervosa. When attention was drawn to model and TP groups, cellular swelling and dead cellular nervosas were indicated. Furthermore, other pathological changes have occurred such as karyopycnosis, gapsinflated, interstitial edema and so forth. TP groups were better than model in terms of pathological changes.1.2 Observed lung tissue by the microscope, angiotelectasis, thickened alveolar and exudation of akaryocytes could be observed in model and TP groups. TP groups were better than model in terms of pathological changes. Moreover, sham operation had no pathological change.1.3 Observed intestine tissue by the microscope, intestinal canals of sham operation had intact intestinal villus, which existed absorptive cells with columnar shape on surface. Furthermore, some lymph cells and plasma cells could be observed between fibrous tissues on lamina propria layer. And there was no edema and fibrosis on stratum submucosum and muscular layer.Some pathological changes, including disappeared intestinal villus, ablated cells, weak primary level and red cells on lamina propria layer could be observed in model.2. The influence of TP on the changes of water content in brain in the model of cerebral ischemic reperfusion injury: Compared with sham operation [(75.6±0.8)%], model [(78.8±0.6)%] significantly increased. Compared with model [(78.8±0.6)%], TP50 [(76.5±2.9)%] , TP100 [(77.2±0.9)%] and nimodipine control [(76.9±1.0)%] significantly decreased (P<0.01).3. The influence of TP on the changes of HSP70 expn in brain in the model of cerebral ischemic reperfusion injury:Compared with sham operation [(3.7±3.9)%], model [(54.6±14.1)%] significantly increased.Compared with model [(54.6±14.1)%], TP50 [(36.9±9.8)%] , TP100 [(19.5±9.8)%] and nimodipine control [(34.9±7.3)%] significantly decreased (P<0.01). Compared between TP50 [(36.9±9.8)%] and TP100 [(19.5±9.8)%], there was significant difference (P < 0.01). Meanwhile, dose-effect relationship could be concluded.4. The influence of TP on the changes of HSP70 expn in lung in the model of cerebral ischemic reperfusion injury:Compared with sham operation [(1.4±0.3)%], model [(39.2±7.9)%] significantly increased.Compared with model [(39.2±7.9)%], TP50 [(13.6±10.4)%] , TP100 [(4.2±0.3)%] and nimodipine control [(3.4±0.9)%] significantly decreased (P<0.01). Compared between TP50 [(13.6±10.4)%] and TP100 [(4.2±0.3)%], there wassignificant difference (P < 0. 01). Meanwhile, dose-effect relationship could be concluded.CONCLUSIONCerebral ischemic reperfusion injury caused brain injured, and also stimulates injury of lungs and intestinal injured. The TP relieved above injury, perhaps, there existed a relationship between mechanisms of anti-oxidation and declining stress reaction.更多还原