基于细胞能量代谢的仙鹤草不同提取物抗脑缺血再灌注损伤作用机制的实验研究

摘要

Objective To screen the effective components of Hairyvein Agrimonia Herb (Agrimonia Pilosa Ledeb,Xianhecao)by exploring the effects and mechanism of Xianhecao on a rat model of cerebral ischemia reperfusion injury.Methods Cerebral ischemia reperfusion injury model was established by middle cerebral artery occlusion (MCAO).SD male rats were randomly divided into six groups:sham group,model group,extract of Xianhecao groups including ethyl acetate extract group (4 g/kg),ethanol extract group (4 g/kg)and water extract group (4 g/kg),nimodipine group (0.5 mg/kg).The rats as-signed to treatment groups were administered corresponding medicines after reperfusion and 6 h after MCAO.The degree of nervous function defect,cerebral infarct volume,and pathomorphological changes in brain (using transmission electron microscope)were evaluated,and the levels of malondialdehyde (MDA)and nitric oxide (NO ),and activity of superoxide dismutase (SOD ) were determined. Results Water extract of Xianhecao attenuate significantly symptoms of nervous function defect(P <0. 05).In addition,water extract decreased the cerebral infarct volume(P <0.01)and attenuate the patho-logical changes of neutrons of cerebral cortex,increased dramatically the activity of SOD after reperfu-sion,and lowered the levels of MDA and NO(P <0.05).Conclusion The water extract of Xianhecao may be the effective components against cerebral ischemia reperfusion injury.The potential mechanism for protecting the tissue and cells in brains is by the way of inhibiting lipid peroxidation reaction and in-creasing the levels of substances of energy in cerebral ischemic region.%目的：探讨仙鹤草抗脑缺血再灌注损伤的作用机制，筛选有效部位。方法采用改良 MCAO法制备脑缺血再灌注损伤模型，将 SD 大鼠随机分为假手术组、模型组、仙鹤草乙酸乙酯提取物组（4 g／kg）、仙鹤草乙醇提取物组（4 g／kg）、仙鹤草水提取物组（4 g／kg）、尼莫地平组（0．5 mg／kg）。分别于再灌注0、6 h 分组灌胃给药，观察各组对脑缺血再灌注引起的神经功能缺损症状、脑梗死体积及脑组织病理学（透射电镜）的调控作用，以及对脑组织中超氧化物歧化酶（SOD）、丙二醛（MDA）、一氧化氮（NO）的调控作用，探讨其抗脑缺血再灌注损伤的作用机制，筛选不同提取物中的有效部位。结果仙鹤草水提取物能明显减轻大鼠的神经功能缺损症状（P ＜0．05）；通过 TTC染色及电镜观察，仙鹤草水提取物能明显缩小脑梗死体积（P ＜0．01）及改善大鼠大脑皮质神经元病变，提高大鼠脑缺血再灌后 SOD，显著降低 MDA 含量和 NO 水平（P ＜0．05）。结论仙鹤草水提取物可能成为抗脑缺血再灌注损伤有效部位，其作用机制可能为抑制脂质过氧化反应、增加缺血区脑组织能量物质含量，最终达到防止脑组织细胞损伤的作用。