Effect of propranolol on ischemic myocardial damage and left ventricular hypertrophy following permanent coronary artery occlusion or occlusion followed by reperfusion

This study was designed to assess the effect of propranolol for limiting myocardial damage and hypertrophy in rats with permanent coronary artery occlusion or occlusion followed by reperfusion. Rats were subjected to occlusion of the left main coronary artery for 48 h (MI) or 0.5 h of occlusion followed by reperfusion for 47.5 h (MI/R). Myocardial injury was determined by measuring the depletion of creatine phosphokinase (CK) levels from the left ventricular free wall. In comparison to sham-occluded animals, myocardial CK levels were significantly decreased by 40% in MI + vehicle animals and 30% in MI/R + vehicle animals. Propranolol (0.3 mg/kg 1 min before occlusion followed by 1 mg/kg at 4 and 24 h after occlusion) significantly reduced the loss of myocardial CK-specific activity in MI animals, but failed to prevent the loss of CK-specific activity in animals subjected to coronary artery reperfusion. Left ventricular hypertrophy developed to a similar extent in both vehicle-treated MI and MI/R groups. Propranolol had no effect on the myocardial hypertrophy in MI or MI/R animals. Likewise, in MI/R animals no diminution of polymorphonuclear leukocyte infiltration was seen with propranolol. These data indicate that propranolol had a significant cardioprotective effect in rats with permanent coronary artery occlusion but failed to salvage ischemic tissue, reduce myocardial hypertrophy or mitigate neutrophil infiltration in animals with early reperfusion of the ischemic myocardium. These results suggest that propranolol may afford a significant protection of the ischemic myocardium, but the combination of reperfusion and propranolol may not result in any greater reduction in infarct size than reperfusion alone.     

柚皮素对缺血再灌注损伤心肌保护作用的机制研究

目的探讨柚皮素(NAR)对心肌缺血再灌注(MI/R)损伤的保护作用及其作用机制。方法通过结扎左冠脉前降支30 min,再灌注120 min,建立MI/R大鼠模型,随机分为NAR高、中、低剂量组(100、50、25 mg/kg),假手术组,模型组,各10只。各组于术前1周开始腹腔注射给药,1次/d。再灌注后取血清,采用比色法测定肌酸激酶(CK)和乳酸脱氢酶(LDH)活性,ELISA法测定肿瘤坏死因子-α(TNF-α)和白介素-1β(IL-1β)水平;取心脏,染色法测定心肌梗死面积;取心肌匀浆,测定髓过氧化物酶(M PO)活力。结果 NAR高剂量组可使心肌梗死面积缩小至32.91%,与模型组(39.78%)比较差异有统计学意义(P<0.05);NAR各剂量组血清CK、LDH活性均降低,与模型组比较差异有统计学意义(P<0.05或P<0.01);NAR各剂量组心肌MPO活力均明显降低(P<0.05或P<0.01);NAR高、中剂量均可降低血清TNF-α和IL-1β水平(P<0.05或P<0.01),低剂量亦可降低血清IL-1β水平(P<0.05)。结论 NAR预处理可保护MI/R所致心肌损伤,其机制与抑制中性粒细胞浸润、减少炎性细胞因子的释放等有关。     

丹参对大鼠心肌缺血再灌注损伤保护作用的实验研究

目的：观察丹参对大鼠心肌缺血再灌注损伤的保护作用。方法取健康雄性大鼠150只,根据数字表法随机分为五组：即假手术组、模型组、丹参高剂量组（100 mg／kg）、中剂量组（30 mg／kg）、低剂量组（10 mg／kg）。丹参组分别于术前灌胃给药,每天1次,连续3 d;假手术组和模型组灌以等量0．9％氯化钠注射液。采用在体大鼠结扎冠状动脉30 min然后松扎冠状动脉180 min造心肌缺血再灌注损伤模型。测定心肌梗死范围,测定血清磷酸肌酸激酶（ CK）、乳酸脱氢酶（ LDH）。结果模型组与假手术组相比,心肌梗死范围及血清CK、LDH活性均显著增加（t＝14．382、21．460,均P＜0．05）。不同剂量丹参组均能明显缩小大鼠心肌缺血再灌注损伤的心肌梗死范围,明显降低血清CK,与模型组比较差异均有统计学意义（ t＝7．426、6．891、11．274,均P＜0．05）。不同剂量丹参组均能明显降低血清LDH,与模型组比较差异均有统计学意义（ t＝22．436、10．843、16．252,均P＜0．05）。结论丹参对心肌缺血再灌注大鼠具有抗氧化应激的作用,对大鼠心肌缺血再灌注损伤具有保护作用。     

槲皮素对心肌缺血再灌注损伤的保护作用及机制研究

目的探讨槲皮素(QU)对心肌缺血再灌注(MI/R)损伤的保护作用及其作用机制。方法采用结扎左冠脉前降支30 min再灌注2 h的方法复制MI/R损伤大鼠模型,随机分为假手术组、模型组、QU组(25、50、100 mg/kg),每组10只,各组于术前1周开始灌胃给药,1次/d。再灌注后取心脏,染色法测定心肌梗死面积;免疫组化法测定心肌组织NF-κB和ICAM-1表达情况;取心肌匀浆,髓过氧化物酶(MPO)法测定中性粒细胞浸润情况。结果QU高、中剂量可分别缩小心肌梗死面积至25.00%、25.31%,与模型组(32.55%)比较差异有统计学意义(P<0.05);QU各剂量组心肌MPO活力分别降低至185.70、190.66、210.03 U/g,与模型组(311.72 U/g)比较差异均有统计学意义(P<0.05,P<0.01);QU各剂量组心肌组织ICAM-1阳性区面积百分比分别降至32.08%、32.65%、36.42%,与模型组(42.67%)比较差异有统计学意义(P<0.05,P<0.01);QU高、中剂量可使心肌NF-κB的表达水平分别降低至55.23%、54.90%,与模型组(61.05%)比较差异有统计学意义(P<0.05)。结论QU预处理可保护MI/R所致心肌损伤,其机制与抑制中性粒细胞浸润、下调NF-κB和ICAM-1的表达等有关。     

阿魏酸钠保护大鼠心肌缺血再灌注损伤的作用机制研究

目的 探讨阿魏酸钠(SF)对心肌缺血再灌注(MI/R)损伤大鼠的保护作用及其机制.方法 40只SD大鼠随机分为假手术组、模型组、SF高剂量组(40 mg/kg)、SF低剂量组(20 mg/kg),每组10只.采用结扎左冠状动脉前降支30 min再灌注2 h的方法 复制MI/R损伤大鼠模型,造模成功后取心脏测定心肌梗死面积、心肌组织细胞间黏附分子-1(ICAM-1)和核因子-κB(NF-κB)表达情况及髓过氧化物酶(MPO)的活力.结果 SF高、低剂量组心肌梗死面积小于模型组(P<0.05,P<0.01).模型组心肌MPO活力和ICAM-1、NF-κB阳性表达率高于假手术组,SF高、低剂量组均低于模型组(P<0.05,P<0.01).结论 SF对心肌MI/R损伤的保护作用是通过抑制中性粒细胞浸润,下调NF-κB和ICAM-1的表达,抑制炎性反应等途径实现的.     

玉郎伞提取物对大鼠心肌缺血再灌注损伤的保护作用

目的:研究玉郎伞(YLS)对心肌缺血再灌注损伤(MIRI)的影响.方法:以Wistar大鼠制备MIRI模型(结扎冠状动脉5 min后再灌注30 min),观察YLS对心肌梗死面积及心肌组织丙二醛(MDA)含量、超氧化物歧化酶(SOD)活力及血清中乳酸脱氢酶(LDH)、肌酸磷酸激酶(CK)活性生化指标的影响.结果:YLS明显降低心肌梗死范围、提高心肌组织中SOD活力、降低其MDA含量,同时降低血清中CK和LDH活力(P<0.01或P<0.05).结论:YLS对大鼠心肌缺血再灌注损伤具有显著的保护作用.     

杜鹃花总黄酮药理性预处理对大鼠心肌缺血/再灌注损伤中炎症反应的影响

目的观察杜鹃花总黄酮(total flavones of rhododendra,TFR)药理性预处理对大鼠心肌缺血/再灌注损伤的保护作用及其对心肌细胞炎症反应的影响。方法在Langen-dorff离体灌流大鼠心脏,采用停灌K-H液30min后再灌注40min的方法制备大鼠心肌缺血/再灌注损伤模型。TFR药理性预处理(TFR pharmacological preconditioning,TFR-PP)大鼠心脏,在缺血前灌注含TFR的K-H液5min,然后用不含TFR的K-H液灌注5min,如此反复,共3次。观察心肌组织病理学损伤,心肌组织中肌酸激酶(CK)、乳酸脱氢酶(LDH)及髓过氧化物酶(MPO)活力的变化,心肌组织中核因子-κB(NF-κB)、肿瘤坏死因子-α(TNF-α)、细胞间粘附分子-1(ICAM-1)的表达。结果在Langendorff离体灌流模型中,TFR-PP(50、100mg.L-1)可明显抑制缺血/再灌注大鼠心肌组织中CK和LDH活性的降低,同时能明显改善心肌组织病理学损伤;TFR-PP(25、50、100mg·L-1)能不同程度的抑制心肌组织中MPO的增加及NF-κB、TNF-α、ICAM-1的表达。结论TFR药理性预处理对大鼠离体心脏缺血/再灌注损伤有明显保护作用,其作用可能与抑制心肌细胞炎症反应有关。     

Palmatine from Coptidis rhizoma reduces ischemia–reperfusion-mediated acute myocardial injury in the rat

The aim of the present study was to evaluate the protective effect of palmatine, one of active ingredients of Coptidis rhizoma, against myocardial ischemia–reperfusion (I/R) injury is due to its antioxidant and anti-inflammatory action. Adult male rats were subjected to 30 min of ischemia and 6 or 24 h of reperfusion. Rats were randomized to receive vehicle or palmatine 1 h before reperfusion. Infarct size, myocardial function, and the antioxidant enzyme activity, such as malonaldehyde (MDA), lactate dehydrogenase (LDH), creatine phosphokinase (CK), superoxide dismutase (SOD) and catalase (CAT) were measured. Palmatine significantly improved I/R-induced myocardial dysfunction by increasing the values of the first derivative (±dp/dt) of left ventricular pressure and decreased infarct size by 50% (P < 0.01 versus vehicle). As expected, palmatine markedly inhibited the increase of LDH, CK, and MDA contents in I/R rat serum, and it also significantly inhibited the decline of the activity of SOD and CAT in I/R cardiac tissues. In addition, COX-2 and iNOS expression in I/R myocardium was significantly reduced. Interestingly, plamatine increased heme oxygenase (HO)-1 induction in human aortic endothelial cells. We concluded that palmatine protects hearts from I/R injury in rats possibly by reducing oxidative stress and modulating inflammatory mediators.     

孟鲁司特钠的心肌保护作用及对一氧化氮合酶的影响

目的观察白三烯受体拮抗剂孟鲁司特钠对大鼠心肌坏死的保护作用及一氧化氮合酶（NOS）的影响。方法大鼠sc异丙肾上腺素（2 mg·kg^-1）造成心肌坏死模型，ig不同剂量孟鲁司特钠，测定血清乳酸脱氢酶（LDH）、肌酸磷酸激酶（CK）、丙二醛（MDA）及心肌一氧化氮（NO）含量和坏死心肌面积，免疫组化检测心肌NOS 3种同功酶的表达。结果大鼠预先给予孟鲁司特钠10或30 mg·kg^-1可降低血清LDH，CK，MDA含量，缩小心肌坏死面积。孟鲁司特钠30 mg·kg^-1还能激活内皮型NOS（eNOS）表达，抑制诱导型NOS（iNOS）表达，促进心肌NO释放。结论孟鲁司特钠通过拮抗白三烯的致炎作用及激活eNOS、抑制iNOS表达，对大鼠异丙肾上腺素心肌坏死具有保护作用，在心肌缺血治疗中有潜在应用前景。     

参麦注射液对抗大鼠心肌缺血再灌注性心律失常作用

目的:探讨参麦注射液对抗大鼠心肌缺血再灌注性心律失常的影响及其作用机制.方法:结扎/松解Wistar大鼠左冠状动脉前降支,建立假手术组(Sham)、缺血组(MI)、再灌注组(MI/R)、参麦组(SM)动物模型.动态Ⅱ导联心电图监测各组心律失常发生率及持续时间,再灌注15 min和60 min S-T段改变;免疫组化技术和图像分析技术检测心肌细胞内HSP70表达;硫代巴比妥酸(TBA)法和黄嘌呤氧化酶法分别测心肌组织丙二醛(MDA)含量及超氧化物歧化酶(SOD)活力;优化紫外分光光度法测血清肌酸激酶(CK)活性.结果:(1)SM组心律失常发生率及持续时间均明显低于其他各组,S-T段降低(P＜0.05).(2)SM组心肌组织HSP70表达量、SOD活力高于MI/R组(P＜0.05),MDA含量及血清CK活性低于MI/R组(P＜0.05).结论:参麦注射液有效地对抗再灌注损伤所致的心律失常的发生率及持续时间,其作用机制可能与增加再灌注心肌组织HSP70含量、SOD活性,减少膜脂质过氧化,稳定膜结构有关.     

氯氨酮对大鼠心肌缺血再灌注心肌细胞凋亡和Fas蛋白、Bcl-2蛋白表达的影响

目的:探讨氯胺酮作用下大鼠实验性心肌缺血再灌注时心肌细胞凋亡与Fas及Bcl-2蛋白表达的变化及与心肌组织损伤的关系,并分析心肌组织病理学损伤程度。方法:以穿线结扎或松扎左冠状动脉制备大鼠心肌缺血再灌注模型。32只大鼠随机分成假手术组(假手术4.5 h)、缺血再灌注组(缺血30min、再灌注4 h)、低剂量氯胺酮+缺血再灌注组(缺血30min、再灌注4h)及高剂量氯胺酮+缺血再灌注组(缺血30min、再灌注个4 h)。以缺口末端标记法检测心肌细胞凋亡的变化,S-P免疫组化法分别检测Fas与Bcl-2蛋白水平变化,做病理组织切片检查心肌损伤情况。结果:心肌缺血再灌注后心肌细胞凋亡指数及Fas蛋白阳性染色指数与Bcl-2蛋白阳性染色指数均增加,氯氨酮可减少心肌凋亡,减少Fas和Bcl-2蛋白阳性细胞表达;心肌缺血再灌注后心肌组织呈大小不一的灶性坏死,坏死周围有炎性细胞浸润,氯胺酮作用后坏死减轻,低剂量氯胺酮作用更明显。结论:心肌缺血再灌注时心肌细胞凋亡、Fas基因的蛋白与Bcl-2蛋白表达量均增加,氯氨酮可减少心肌凋亡,减少细胞Fas和Bcl-2蛋白阳性表达,从而减轻心肌损伤,且低剂量氯氨酮作用更明显。     

Reduction in myocardial ischemic/reperfusion injury and neutrophil accumulation after therapeutic administration of streptokinase.

The benefit of thrombolytic agents to reduce myocardial infarct size, improve left ventricular (LV) function, and prolong survival in human subjects is generally recognized, although the precise mechanism is poorly defined. This study was designed to evaluate the cardioprotective effects of streptokinase (SK) in rats, a species less responsive to plasminogen activators, using a model of mechanical occlusion and release of the left coronary artery. Myocardial injury and polymorphonuclear leukocyte (PMN) infiltration were determined by measuring creatine phosphokinase (CPK) specific activity and myeloperoxidase (MPO) activity, respectively, in the LV free wall (LVFW). After coronary artery occlusion for 0.5 h and reperfusion for 24 h (myocardial ischemia, MI/R), CPK specific activity decreased from 7.0 +/- 0.3 U/mg protein in the sham + vehicle group to 5.6 +/- 0.5 U/mg protein in the MI/R + vehicle group (n = 19, p less than 0.01), while MPO activity increased from 0.14 +/- 0.03 U/g tissue in the sham + vehicle group to 2.8 +/- 0.7 U/g in the MI/R + vehicle group (p less than 0.001). Administration of SK (100,000 IU/kg + 50,000 IU/kg/h for 2 h beginning 15 min before coronary artery reperfusion) reduced the loss of CPK specific activity from reperfused myocardium (6.8 +/- 0.5 U/mg protein, n = 23, p less than 0.05 as compared with the MI/R + vehicle group) and attenuated the increase in MPO activity (1.3 +/- 0.4 U/g tissue, p less than 0.05 as compared with the MI/R + vehicle group). This dose of SK did not change plasma fibrinogen concentration, slightly reduced plasminogen activity (i.e., 20% from control value), and markedly reduced alpha 2-antiplasmin activity (i.e., 60% from control values). A lower dose of SK (i.e., 10,000 IU/kg + 5,000 IU/kg/h for 2 h) did not reduce myocardial injury, did not attenuate the increase in MPO activity, and had no effect on the measured hemostatic parameters. Survival in all MI/R groups ranged from 62 to 66%, and there were no differences in survival between any of the groups (p greater than 0.05). In a model of arachidonic acid-induced rat hindpaw inflammation, SK had no effect on the increase in MPO activity, suggesting that the increase in myocardial MPO activity was not due to a direct effect on inflammatory cell accumulation. In in vitro studies, SK (1-1,000 U/ml) did not scavenge superoxide anion produced by purine (10 mM) and xanthine oxidase (10 mU/ml), nor did it reduce superoxide release, beta-glucuronidase release, or neutrophil aggregation of rabbit peritoneal neutrophils activated with fMLP.(ABSTRACT TRUNCATED AT 400 WORDS)     

葡萄籽原花青素对大鼠心肌缺血再灌注损伤的保护作用

目的研究葡萄籽原花青素对大鼠心肌缺血再灌注损伤的保护作用。方法 SD大鼠50只随机等分为5组:假手术组、模型组、葡萄籽原花青素低、中、高剂量组。结扎大鼠左冠状动脉前降支,30 min后剪断结扎线形成再灌注模型。测定5组大鼠在1 h后的血清肌酸激酶(CK)、乳酸脱氢酶(LDH)、谷草转氨酶(AST)、超氧化物歧化酶(SOD)和丙二醛(MDA)的含量,并比较心肌梗死面积。结果不同剂量的葡萄籽原花青素(50～200 mg/kg)均可降低大鼠CK、LDH、AST和MDA的水平,提高大鼠体内SOD的水平,还能有效降低大鼠心肌梗死的面积,与模型组比较,均有显著差异(P<0.05)。结论葡萄籽原花青素可以显著的改善心肌缺血再灌注大鼠体内的生化指标,减少心肌梗死的面积,对于心肌缺血再灌注具有很好的保护作用。     

前列地尔与川芎嗪、黄芪合用对大鼠心肌缺血再灌注损伤的保护作用

目的 :观察前列地尔与川芎嗪 (LT )、黄芪(AM ) 3药合用对大鼠心肌缺血再灌注损伤的保护作用。方法 :采用在体大鼠开胸结扎冠状动脉左室支 30min后 ,松扎再灌注 60min造成心肌缺血再灌注模型并以 0 .9%氯化钠注射液为模型对照 ,观察 3药 :前列地尔 31.2 5μg·kg- 1,川芎嗪 2 5mg·kg- 1,黄芪 4 15mg·kg- 1合用对再灌注心肌组织中超氧化物歧化酶 (SOD)、谷胱甘肽过氧化物酶(GSH PX)活力 ,丙二醛 (MAD)、Ca2 +含量及血清肌酸磷酸激酶同功酶 (CK MB)含量的变化 ,并同时心电图监测心律失常情况。结果 :与模型对照组相比3药合用可提高再灌注心肌组织中SOD ,GSH PX活力 ,差异有非常显著意义 (P <0 .0 1) ;并能降低再灌注心肌组织中MDA ,Ca2 +含量及血清CK MB含量 ,差异有非常显著意义 (P <0 .0 1) ;防止再灌注室性心律失常的发生 ,缩短心律失常的维持时间 ,降低ST段抬高的程度 ,差异有非常显著意义 (P <0 .0 1)。结论 :前列地尔与LT ,AM合用在保护心肌缺血再灌注损伤中有显著的作用 ,其保护作用主要与清除自由基有关     

磷酸肌酸联合缺血后适应对大鼠心肌缺血/再灌注损伤的保护作用

目的探讨磷酸肌酸后适应联合缺血后适应对大鼠心肌缺血/再灌注损伤的作用。方法取健康、♂、SPF级Wistar大鼠40只,体质量260～290 g。随机分成4组(各组10只):缺血/再灌注组(I/R组)、缺血后适应组(IPost组)、磷酸肌酸后适应组(PCr组)、磷酸肌酸后适应+缺血后适应组(PCr+IPost组),均给予心肌缺血30 min,再灌注120 min处理。再灌注2 h后用比色法测量各组大鼠血清肌酸激酶(CK)、乳酸脱氢酶(LDH)、髓过氧化物酶(MPO)活性;ELISA方法检测血清肿瘤坏死因子-α(TNF-α);Western blot方法检测缺血心肌磷酸化的蛋白激酶B(P-Akt)、Bcl-2蛋白表达;TTC染色测定心肌梗死面积。结果 IPost、PCr组血清CK、LDH、MPO、TNF-α及心肌梗死面积明显低于I/R组,PCr+IPost组较IPost、PCr组各项指标进一步降低;而IPost、PCr组心肌组织P-Akt、Bcl-2蛋白水平明显高于I/R组,PCr+IPost组较IPost、PCr组蛋白水平进一步升高。结论磷酸肌酸后适应联合缺血后适应可以明显减轻大鼠心肌缺血/再灌注损伤,其作用机制可能与共同激活PI-3K/Akt/Bcl-2信号通路及抑制炎症反应有关。     

前列腺素E_1、川芎嗪合用对大鼠心肌缺血再灌注损伤的保护作用

目的观察前列腺素Ｅ１（３１２５μｇ·ｋｇ－１）与川芎嗪（２５ｍｇ·ｋｇ－１）合用对大鼠心肌缺血再灌注损伤的影响。方法麻醉大鼠冠脉结扎３０ｍｉｎ后，再灌６０ｍｉｎ诱发心律失常，硫代巴比妥酸法和分光光度法分别测定ＭＤＡ、ＳＯＤ及ＧＳＨ Ｐｘ，原子吸收光度法测定心肌细胞内Ｃａ２＋含量。结果两药小剂量合用的效果优于各药较大剂量单用。联合用药不仅更显著提高缺血再灌心肌ＳＯＤ、ＧＳＨ Ｐｘ活力（Ｐ＜００１），尚可显著降低ＭＤＡ、Ｃａ２＋及血清ＣＫ ＭＢ含量（Ｐ＜００１），防止缺血再灌室性心律失常的发生（Ｐ＜００１）。结论前列腺素Ｅ１与川芎嗪合用对心肌缺血再灌注损伤的保护作用有显著的协同作用。其作用与提高自由基清除酶活性、抑制脂质过氧化反应和防止心肌细胞内“钙超负荷”有关     

Cyclosporin-A reduces leukocyte accumulation and protects against myocardial ischaemia reperfusion injury in rats

The present study was designed to evaluate the effect of cyclosporin A in a rat model of myocardial ischaemia reperfusion injury (MI/R). Anaesthetized rats were subjected to total occlusion (20 min) of the left main coronary artery followed by 5 h reperfusion (MI/R). Sham myocardial ischaemia-reperfusion rats (Sham MI/R) were used as controls. Myocardial necrosis, myocardial myeloperoxidase activity (MPO), serum creatinine phosphokinase activity (CPK), serum tumor necrosis factor (TNF-α), cardiac mRNA for TNF-α, cardiac intercellular adhesion molecule-1 (ICAM-1) immunostaining and myocardial contractility (left ventricle dP/dt_max) were evaluated. Myocardial ischaemia plus reperfusion in untreated rats produced marked myocardial necrosis, increased serum CPK activity and myeloperoxidase activity (a marker of leukocyte accumulation) both in the area-at-risk and in the necrotic area, reduced myocardial contractility and induced a marked increase in the serum levels of the TNF-α. Furthermore increased cardiac mRNA for TNF-α was measurable within 10 to 20 min of left main coronary artery occlusion in the area-at-risk and increased levels were generally sustained for 0.5 h. Finally, myocardial ischaemia-reperfusion injury increased ICAM-1 staining in the myocardium. Administration of cyclosporin A (0.25, 0.5 and 1 mg/kg as an i.v. infusion 5 min after coronary artery occlusion) lowered myocardial necrosis and myeloperoxidase activity in the area-at-risk and in the necrotic area, decreased serum CPK activity, increased myocardial contractility, reduced serum levels of TNF-α and the cardiac cytokine mRNA levels, and blunted ICAM-1 immunostaining in the injured myocardium. The data suggest that cyclosporin A suppresses leukocyte accumulation and protects against myocardial ischaemia-reperfusion injury.     

蜂胶总黄酮对大鼠心肌缺血-再灌注损伤的保护作用

目的　研究蜂胶总黄酮对大鼠心肌缺血-再灌注损伤的影响。方法　制备大鼠心肌缺血-再灌注损伤模型, 研究蜂胶总黄酮对其血清中MDA和SOD以及NO的影响,同时以电镜和光镜观察了其病理组织形态。结果　HE染色组织形态学观察显示,与模型组比较,蜂胶总黄酮组的细胞形态有明显的改善,炎细胞浸润也有减轻;电镜超微结构显示,蜂胶总黄酮组的心肌细胞超微结构与模型组相比亦有不同程度的改善;从各组心肌三酶均值水平来看,蜂胶总黄酮组与模型组比较均有不同程度的降低作用(P<0 05);并可明显降低MDA含量,增强SOD活力,还可增加NO含量。结论　蜂胶总黄酮对大鼠心肌缺血-再灌注损伤具有明显的保护作用。     

黄芩苷对大鼠心肌缺血再灌注损伤的保护作用(英文)

目的：研究中药有效成分黄芩苷(baicalin)对大鼠心肌缺血再灌注损伤的作用及其机制。方法：雄性Wistar大鼠随机分为4组,假手术组、对照组和黄芩苷50,100 mg·kg~(-1)组。结扎大鼠左冠状动脉前降支30 min后松开结扎线120 min复制心肌缺血-再灌注损伤模型,以多道生理记录仪持续记录左室压力变化速率(±dp/ dt_(max))和左室舒张末期压(LVEDP)的变化。检测心肌丙二醛(MDA)含量、超氧化物歧化酶(SOD)、Na~+-K~+-ATP酶和Ca~(2+)-ATP酶活性以及血清乳酸脱氢酶(LDH)和磷酸肌酸激酶(CK)含量,以透射电镜观察心肌超微结构的改变。结果：与假手术组比较,对照组大鼠左室±dp/dt_(max)明显降低(P＜0.01),而LVEDP明显升高(P＜0.01)。静脉注射黄芩苷50,100 mg·kg~(-1)可使降低的±dp/dt_(max)明显升高(P＜0.05,P＜0.01),升高的LVEDP显著降低(P＜0.05,P＜0.01)。黄芩苷组血清CK和LDH含量分别是(72±19)kU·L~(-1),(64±15)kU·L~(-1)和(1 365±209)U·L~(-1),(1 124±169)U·L~(-1),均明显低于对照组[(90±23)U·L~(-1)和(1 826±123)U·L~(-1),P＜0.01]。对照组大鼠心肌SOD,Na~+-K~+-ATP酶和Ca~(2+)-ATP酶活性均明显低于假手术组,而降低的酶活性可被预先给予黄芩苷所升高(P＜0.05,P＜0.01)。此外,黄芩苷还可降低缺血心肌MDA含量,改善心肌超微结构。结论：黄芩苷通过清除氧自由基,抗脂质过氧化,改善心肌ATP酶活性而保护心肌缺血再灌注损伤。