【作者】 高卫真；

【导师】 娄建石； 刘艳霞；

【作者基本信息】 天津医科大学 ， 心血管药理学， 2003， 硕士

【摘要】 目的：研究黄芪苷Ⅳ（AST）对氧自由基（OFR）所致心肌损伤的保护作用，并探讨其作用机制。 方法：用阿霉素（ADR）制备心肌OFR损伤模型。实验分为两个部分：第一部分—整体动物实验，实验分3组，模型组（ADR组）：以大鼠腹腔注射ADR4.5mg／kg／d，共2日，建立OFR心肌损伤模型；预防组（ADR+AST组）：在注射ADR前30分钟腹腔注射AST2.0mg／kd／d，共2日：正常对照组，每日腹腔注射生理盐水1 ml／kg，共2日。给药后第5天，测定心肌组织中MDA含量和SOD活性，并取心室肌在电镜下观察心肌超微结构的改变。第二部分—细胞实验，以原代培养乳鼠心肌细胞建立OFR损伤模型，即ADR组为ADR（0.5mg／L和1.0mg／L）与乳鼠心肌细胞共同培养24小时，ADR+AST组为在加入ADR前1小时给予AST（10mg／L和20mg／L），然后加入与ADR组浓度相同的ADR培养24小时，观察心肌细胞MTT代谢率、MDA含量及NOS活性的变化，并测定心肌细胞内游离Ca²⁺浓度的改变。 结果： 一、整体动物实验 1．MDA含量：与正常对照组（1.39±0.25 nmol／mg protein）相比，ADR组（1.88±0.42nmol／mg protein）心肌组织的MDA含量增高（P＜0.05），与ADR组相比，ADR+AST组（1.32±0.36nmol／mg protein）MDA值降低（P＜0.05）。 2．SOD活性：与正常对照组（33.0±3.21 U／mg protein）相比，ADR组（36.5±1.97 U／mg protein）和ADR+AST组（36.9±3.12 U／mg protein）心肌组织的SOD活性均明显增高（P＜0.05）。天津医科大学硕士月开究生学位论文’中文摘要 3.心肌超微结构:电镜观察显示，ADR组心肌线粒体增生、扭曲、变形，T管扩张，心肌间质水肿及微血管痉挛;而ADR+AST组上述病理改变明显减轻。 二、原代培养心肌细胞实验 1.M，IT代谢率:与正常对照组（100士o%）比较，ADR两个剂量组（o.sm叭，l.omg/L）的MTT代谢率（60.74士10.63%，55.99士4.04%）均明显降低（p<0.02），以高剂量组降低更为明显;AST大小剂量对正常心肌细胞的MTT代谢率（94.73士9.48%，96.18士6.39%）均没有影响（P>0.05），但可提高ADR损伤心肌细胞的MTT代谢率，在ADR剂量相同的条件下，大剂量AST升高程度更为明显。 2.MDA含量:与正常对照组（5 .77士1.43nrn。腼9 protein）相比，ADR组（9.65士1.43 nmo腼9 nrotein）MDA含量显著增高（p<0.05），与ADR组相比，ADR+AsT大小两个剂量组的MDA值（6.73士2.84 nxnol/m 9 protein，3.84士0.87nlnof/m gProtein）均明显降低（P<0.05），大剂量AST降低更为显著（P<0.01）。 3.NOS活性:与正常对照组（26.96士1.68U/mgProtein）比较，ADR组（38.62士1.56U/mgprotein）NOS活性明显升高（P<0.05），与ADR组比较，ADR+AsT大小两个剂量组的Nos活性（22.68士5.6oU/mg protei几19.67士l.23U/mgprotein）均明显降低，高剂量组降低更为明显（P<0.01）。 4.[eaZ勺i:与正常对照组（225.14士21.91 nmoljL）比较，心R组（357.00士46.53tnno讥）[eaZ勺i明显升高（P<0.01），与心R组比较，AnR+AsT组（155.64士28.05 nmol几）[eaZ+]i显著降低（P<0.01）。结论:1.黄茂昔W提高心肌细胞SOD的活性，降低MDA的含量。2.黄茂昔W剂量依赖地提高ADR抑制的心肌细胞MTT代谢率。3.黄蔑昔W降低ADR导致的NOS活性的增高和对抗可能由此产生的过，反匀卜医耳牛大月卜月阿d匕友开，匕月匕学位论文量NO造成的心肌线粒体损伤。中文摘要4.黄茂昔W降低由ADR引起的心肌细胞内C扩+超载。更多还原

【Abstract】 OBJECTIVE: To investigate protective effects and mechanisms of astragaloside IV on myocardium injury caused by free radicals.METHODS: Adriamycin (ADR) was administered intraperitoneally to establish the model of myocardium injury caused by oxygen free radicals in rats. Experiments were performed in vivo and in vitro, respectively. In vivo experiments: rats were divided into three groups randomly: the model group (ADR group) received ADR (4.5 mg/kg) intraperitoneally for 2 days; the prophylaxes group (ADR±AST group) received same dose of ADR 30 minutes after being treated with astragaloside IV (AST) (2.0 mg/kg) every day for 2 days; the control group received normal saline (1 ml/kg) intraperitoneally in stead of drugs for 2 days. On the fifth day after treatment with drugs, content of MDA and activity of SOD in myocardium tissue were measured. Ultrastructure of ventricular muscle was observed under the electronic microscope. In vitro experiments: myocytes of new-born rats were incubated with ADR (0.5mg/L and 1.0 mg/L) for 24 hour to induce oxygen free radical injury in model group; same dose of ADR was administered 1 hour after treatment with AST (10 mg/L and 20 mg/L) in therapeutic group and incubated for another 24 hours. Metabolic rate of MTT, content of MDA, activity of NOS, and intracellular free calcium of cardiac myocyte were measured.RESULTS: Experiment in vivo1. Content of MDA: Compared with that of control group (1.39±0.25 nmol/mg protein) , the content of MDA was increased in ADR group (1.88±0.42 nmol/mgprotein), (p<0.05). Compared with that of model group, the content of MDA was decreased in ADR±AST group (1.32 ±0.36 nmol/mg protein), (p<0.05).2. Activity of SOD: Compared with that of control group (33.0 ± 3.21 U/mg protein), the activities of SOD were increased significantly both in ADR group(36.5 ±1.97 U/mg protein) and in ADR±AST group (36.39 ± 3.12 U/mg protein), QK0.05).3. Ultrastructure of myocardium: Hyperplasia, twisting, deformation of myocardial mitochondria, T-tube dilation, interstitial edema, microvessel spasm of myocardium were showed under the electronic microscope, while the above pathologic alterations were attenuated in ADR±AST group.In vitro experiment1. Metabolic rate of MTT: Compared with that of control group (100.0±0%), metabolic rates of MTT was decreased in ADR 0.5 mg/L and 1.0 mg/L groups in a dose dependent manner significantly (60.74 ± 10.63%, 55. 99 ±4.04% ), (PO.01). Compared with that of control group, metabolic rates of MTT in both the small and the large dosage of AST were 94.73 ±9.48%, 96.1 8 ±6.39 respectively (p>0.05). However, the metabolic rate of MTT in cardiac myocyte injured by ADR could be increased. Under the condition that the dosages of ADR were the same, metabolic rate of MTT in the large dosage of AST was increased much more significantly.2. Content of MDA: Compared with that of control group (5 .77 ±1.43 nmol/mg protein), the content of MDA was increased in ADR group (9.65 ±1.43 nmol/mg protein), (p<0.05). Compared with that of ADR group, the content of MDA was dose-dependently decreased in AST 10 mg/L and 20 mg/L groups significantly (6.73 ±2.84 nmol/mg protein, 3.84±0.87 nmol/mg protein), (p<0.05).更多还原