纳络酮对缺血再灌注心肌脂质过氧化物和钙含量的影响

利用大心肌缺血、再灌注模型，观察了纳络酮对缺血再藻注心肌脂质过氧化物（ＬＰＯ）、超氧化物歧化酶（ＳＯＤ）和钙含量的影响。结果表明：缺血、再灌注心肌ＬＰＯ和钙含量明显增加（Ｐ＜０．０５，Ｐ＜０．０１），再灌注心肌ＬＰＯ含量和钙含量明显高于缺血心肌（Ｐ＜０．０５，Ｐ＜０．０１），而缺血、再灌注心肌ＳＯＤ明显降低（Ｐ＜０．０１）；纳络用明显降低缺血、再灌注心肌ＬＰＯ和钙含量（Ｐ＜０．０５，Ｐ＜００１），但对ＳＯＤ的影响不明显（Ｐ＞０．０５）。提示：纳络酮抑制心肌缺血、再灌注时的脂质过氧化物反应，部份阻止细胞外钙跨膜内流，对心肌只响保护作用。     

瑞舒伐他汀后处理通过抑制高迁移率族蛋白表达减轻心肌缺血再灌注损伤的研究

目的：研究瑞舒伐他汀（RS）后处理是否可以通过抑制高迁移率族蛋白（HMGB1）的表达减轻心肌缺血再灌注损伤（I／R）。方法使用 SD 大鼠缺血再灌注模型,缺血30 min,再灌4 h。将大鼠随机分为假手术组（n＝10）、缺血再灌注组（n＝15）和 RS 后处理组（n＝15）三组,检测血清中乳酸脱氢酶（LDH）水平和肌酸激酶（CK）活性、心肌组织中超氧化物歧化酶（SOD）活性和丙二醛（MDA）水平及心肌梗死面积和心肌中 HMGB1的表达水平。结果 RS 后处理能明显减少梗死面积（P ＜0．05）及 LDH、CK 活性（P 均＜0．05）;明显抑制 MDA 的升高和 SOD 的活性（P 均＜0．05）;明显抑制 HMGB1的表达（P ＜0．05）。结论 RS 后处理对心肌 I／R 的保护作用与抑制 HMGB1的表达有关。     

丹参酮、纳络酮对缺血再灌注心肌局部血流量的影响

目的：观察丹参酮、纳络酮对缺血再灌注心肌局部血流量的影响。方法：用结扎冠状动脉左前降支的方法复制犬心肌缺血再灌注模型，心肌局部血流量用氢气清除法测定。结果：丹参酮、纳络酮均能明显增加正常及部分再灌注心肌血流量，丹参酮主要增加缺血周围区血流量，纳络酮可增加缺血中心区及周围区血流量。结论：丹参酮、纳络酮均能缩小缺血区范围，纳络酮还能减轻缺血程度。     

蝙蝠葛碱抗缺血/再灌注性室颤及其机制

目的：探讨蝙蝠葛碱抗缺血／再灌注性室颤的机理。方法：用高效液相色谱－电化学法测定豚鼠离体心脏灌注液中去甲肾上腺素（NE）含量。结果：蝙蝠葛碱组和维拉帕米组在停止灌注时心脏NE释放量明显低于对照组（P＜0．01），缺血／再灌注性室颤发生率显著低于对照组（P＜0．05）。发生缺血／再灌注性室颤的心脏NE释放量明显高于无缺血／再灌注性室颤心脏（P＜0．01）。停止灌注时心脏NE释放量和缺血／再灌注性室颤发生率，在蝙蝠葛碱组与维拉帕米组之间无显著差异（P＞0．05）。结论：蝙蝠葛碱抑制缺血心肌NE释放为其抗缺血／再灌注性室颤的机理之一。     

纳络酮对缺血再灌注心肌脂质过氧化物和钙含量的影响

利用犬心肌缺血，再灌注模型，观察了纳络酮对缺血再灌注心肌脂质过氧化物（ＬＰＯ），超氧化物岐化酶（ＳＯＤ）和钙含量的影响，结果表明，缺血，再灌注心肌ＬＰＯ和钙含量明显增加（Ｐ〈０．０５，Ｐ〈０．０１）。再灌注心肌ＬＰＯ含量和钙含量明显高于缺血心肌（Ｐ〈０．０５，Ｐ〈０．０１），而缺血，再灌注心肌ＳＯＤ明显降低（Ｐ〈０．０１）；纳络酮明显降低缺血，再灌注心肌ＬＰＯ和钙含量（Ｐ〈０．０５，Ｐ〈０．０１）     

富氢生理盐水对大鼠视网膜缺血再灌注损伤神经保护作用的研究

目的：本文应用大鼠视网膜缺血再灌注损伤模型,探讨富氢生理盐水对其是否具有神经保护作用。方法成年雄性SD大鼠随机分为4组：正常组、视网膜缺血再灌注组（ RIR）、富氢生理盐水组（ HRS）、生理盐水组（ NS）。正常组大鼠不进行任何手术操作,其他3组大鼠均行前房穿刺,造成缺血60min后恢复灌注,RIR 组期间不给予任何干预措施,HRS 组和 NS 组于再灌注前10min 及再灌注开始时分别腹腔内注射3mLHRS或2mL NS。应用免疫组化法观察缺血再灌注损伤视网膜神经节细胞存活情况,另外用相应试剂盒检测再灌注24h及7d后大鼠血清中SOD活性及MDA水平。结果缺血再灌注7d后,RIR组大鼠神经节细胞数明显减少（P＜0．01）,而 HRS 组视网膜神经节细胞数明显较多（P＜0．05）;另外,与正常组相比,RIR组 SOD活性明显降低（P＜0．01）,MDA水平明显升高（24h P＜0．05,7d P＜0．01）,与 RIR 组相比,HRS 组SOD活性显著增加（24h P＜0．05,7d P＜0．01）,7d时MDA含量显著降低（P＜0．01）。结论腹腔内注射富氢生理盐水能够明显减少神经节细胞凋亡,并可显著提高血清中内源性抗氧化酶活性,降低氧化产物水平。     

灯盏花注射液对小鼠肝损伤生化指标的影响

目的：观察灯盏花注射液对小鼠肠缺血再灌注肝损伤生化指标的影响。方法：制作小鼠肠缺血再灌注肝损伤模型。小鼠缺血时间20min,再灌流1h后制备血清;摘取肝脏,制备肝匀浆,测定肝脏超氧化物歧化酶（SOD）活性和丙二醛（MDA）含量。结果：小鼠血清ALT明显增高,灯盏花注射液能降低缺血再灌注肝损伤小鼠血清ALT的活性（P＜0．01）;还可使SOD活性和MDA含量明显恢复（P＜0．05或P＜0．01）。结论：灯盏花注射液可改善小鼠肠缺血再灌注肝损伤时生化指标,提示灯盏花注射液对小鼠肠缺血再灌注肝损伤有保护作用,且肝保护作用机制与其抗氧化作用有关。     

左旋卡尼汀对大鼠心脏缺血-再灌注损伤能量代谢的影响

目的：观察左旋卡尼汀对离体大鼠心脏缺血-再灌注损伤的作用及对心肌细胞能量代谢的影响。方法：将制备成功的Langendorff离体心脏模型随机分成3组（各8只）。正常对照组（CON组）：K—H液灌注65min；左旋卡尼汀组（L—CAR组）：离体心脏用K—H液平衡15min后，K—H液中加入5mmol／L左旋卡尼汀继续灌注20min．然后全心停灌20min，再用相同的液体复灌30min；心肌缺血-再灌注组（MIRI组）：整个实验过程同L—CAR组．但灌注液中不含左旋卡尼汀。比色法测定冠脉流出液中乳酸脱氢酶（LDH）含量，高效液相色谱法测定再灌注末心肌组织中腺苷酸的含量。结果：缺血前各组LDH活性差异无统计学意义（P〉0．05），再灌注末L—CAR组LDH含量明显低于MIRI组（P〈0．01），而心肌组织ATP、ADP、总腺苷酸水平及能荷则高于该组（P〈0．05，P〈0．01）。结论：左旋卡尼汀对缺血-再灌注心肌有保护作用，其保护机制与改善心肌能量代谢有关。     

大鼠肝缺血再灌注后肺细胞凋亡及七氟醚对细胞凋亡及 NF-κBp65的影响

目的：探讨七氟醚预处理对大鼠肝缺血再灌注后肺细胞凋亡的影响。方法24只Wister大鼠随机分为3组（n＝8）：假手术组,缺血再灌注组,七氟醚组,阻断肝门30 min后建立大鼠70％肝缺血再灌注模型。假手术组（ S组）仅游离肝门,但不阻断;肝缺血再灌注组（ IR组）采用阻断肝门30 min,再灌注1 h的方法制备大鼠肝缺血再灌注损伤模型;七氟醚预处理组（ SP组）吸入2．1％七氟醚30 min,停止吸入10 min后制备肝缺血再灌注模型。于再灌注1 h时处死动物,留取肺组织,测定湿／干重比（ W／D比）,采用比色法检测超氧化物歧化酶（ SOD）活性及丙二醛（ MDA）含量,采用原位末端转移酶法（ TUNEL）检测细胞凋亡,计算细胞凋亡指数（ AI）,采用Western blot法测定核蛋白NF-κBp65表达,光镜下观察肺组织病理学结果。结果与S组比较,IR组和SP组再灌注各时点肺组织W／D比值、细胞凋亡指数（ AI）和NF-κB 活性水平及MDA含量均显著增高（均P＜0．05）;SOD活性显著降低（P＜0．05）;与IR组比较,SP组W／D比值、细胞凋亡指数（AI）、NF-κB表达水平与MDA含量显著降低（均P＜0．05）;而SOD活性显著增加（P＜0．05）;SP组肺组织损伤较IR组减轻。结论细胞凋亡可能在肝缺血再灌注肺损伤发生过程中具有重要意义;七氟醚对大鼠肝缺血再灌注后肺细胞凋亡具有抑制作用,其作用机制可能通过降低肺组织NF-κB的活性,从而清除自由基、抑制脂质过氧化有关。     

纳络酮治疗急性重型颅脑损伤的疗效观察

目的：探讨纳络酮治疗重型颅脑损伤的疗效。方法：98例急性重型颅脑损伤病人分成纳络酮治疗组（52例）与常温治疗组（46例），观察病人神志、颅内压与治疗效果，并行统计学分析比较。结果：纳络酮组病人伤后颅内压升高的幅度显著低于对照组（P＜0．05），纳络酮组伤后1周意识转清醒（23／52）显著高于对照组（13／46）（P＜0．05）。纳络酮组与对照组死亡分别为10／52和14／46。恢复良好分别为27／52和15／46，纳络酮组均优于对照组（P＜0．05）。结论：纳络酮可以降低急性重型颅脑损伤病人颅内压的升高幅度，缩短昏迷时间，提高急性重型颅脑损伤的治疗效果。     

纳络酮对犬心肌腺苷酸环化酶活性的影响

用硬脂酸为基质制成苦参洗头膏，用于洗头治疗脂滥性皮炎，有效率为94．9％。该制剂疗效满意，兼有日用洗涤剂的特点，使用方便．患者乐于接受。     

迷走神经刺激预处理对急性心肌缺血大鼠心肌P物质和降钙素基因相关肽的影响

目的观察迷走神经刺激预处理对急性心肌缺血大鼠心肌组织缺血区和非缺血区P物质(SP)和降钙素基因相关肽(CGRP)表达的影响。方法健康成年雄性SD大鼠24只,体质量270~300g,随机分为3组,每组8只,假手术组(S组)、单纯冠状动脉结扎组(I组)和迷走神经刺激预处理冠状动脉结扎组(VS组)。S组大鼠开胸后在冠状动脉左前降支下穿线不结扎;Ⅰ组大鼠开胸后结扎冠状动脉左前降支;VS组大鼠实施迷走神经刺激30min后结扎冠状动脉左前降支。各组在手术后计时3h。采用免疫组织化学、酶免疫法和反转录-聚合酶链反应法从蛋白和基因水平观察各组大鼠缺血区和非缺血区心肌SP和CGRP的表达。结果Ⅰ组大鼠缺血区心肌SP/SP mRNA和CGRP/β-CGRP mRNA的水平较S组升高(P<0.05),VS组低于Ⅰ组(P<0.05),但仍高于S组(P<0.05)。非缺血区各组的变化趋势类同缺血区,但各扎闭冠状动脉组SP/SP mRNA和CGRP/β-CGRP mRNA的水平均低于相应组缺血区的水平(P<0.05)。结论迷走神经刺激预处理可降低急性心肌缺血大鼠心肌组织SP和CGRP的表达,提示迷走神经刺激预处理可能参与缺血心肌的保护。     

Beneficial effect of nipradilol (K-351) on acute myocardial ischemia. Study of the relationship between regional myocardial blood flow and energy metabolism

To examine the effects of nipradilol on ischemic myocardium, experiments were performed on regional myocardial blood flow (MBF) and energy metabolism in anesthetized, open-chest dogs. Nipradilol at a dose of 0.3 mg/kg was i.v.-administered 10 min after coronary ligation. MBFs at various sites, including ischemic and non-ischemic areas, were determined by the hydrogen gas clearance method. The levels of ATP and creatine phosphate (CP) at the site of MBF determination were measured 60 min after ligation, and mitochondrial function (RCI, QO2) in the ischemic and non-ischemic areas was determined. Following nipradilol administration, aortic pressure and heart rate were significantly lowered. In ischemic areas with MBF below 40 ml/min/100 g, nipradilol had no influence on MBF. However, the tissue level of ATP in nipradilol treated hearts was significantly higher as compared with untreated hearts. In the area of mild ischemia with MBF of 40-60 ml/min/100 g, nipradilol preserved the tissue ATP and CP levels in spite of a decrease in MBF. Moreover, an inhibition of the decrease in mitochondrial respiratory function was observed in ischemic areas with MBF below 20 ml/min/100 g. Thus, nipradilol administered following ischemia preserved ATP content and mitochondrial function in the ischemic myocardium with reduction of heart rate and aortic pressure. This suggests that nipradilol exerts a cardioprotective effect in acute ischemia. It seems that the cardioprotective effect is due to a decrease in myocardial oxygen demand and preservation of mitochondrial function.     

Adrenergic influences on ischemic and reperfusion arrhythmias in a canine model with diminished collateral blood flow

To examine the role of adrenergic influences on genesis of ischemic and reperfusion arrhythmias, the left anterior descending coronary artery (LAD) was cannulated and perfused by a shunt from the left carotid artery in 38 open-chest pentobarbital-anesthetized dogs. Ischemia was produced by shunt occlusion and retrograde diversion of collateral flow from the LAD. The diverted blood was collected and returned to the animal by intravenous (i.v.) injection. The shunt was opened and the ischemic myocardium reperfused after 30 min of ischemia. Microsphere injections in six dogs during shunt occlusion and retrograde bleeding showed that blood flow to the ischemic zone was less than 1.5% of normal zone flow. The remaining 32 dogs were randomized into four treatment groups. Dogs (n = 8) were treated before shunt occlusion with either saline, nadolol (1 mg/kg), prazosin (0.2 mg/kg), or bilateral stellate transection. As compared with saline treatment, nadolol and stellate transection significantly reduced heart rate (HR), and prazosin significantly reduced mean arterial blood pressure (MAP) (p less than 0.05). However, none of the antiadrenergic interventions significantly reduced the number or frequency of ectopic beats during either the 1a or 1b phases of ischemia. None of the 32 dogs developed ventricular fibrillation (VF) during ischemia, but all dogs fibrillated within 30 s of reperfusion. The size of the ischemic zone ranged from 21 to 38% of the left ventricle, and there were no differences among the four treatment groups. The results suggest that when ischemia is severe, the adrenergic nervous system does not play a significant role in genesis of ischemic-induced ectopy or reperfusion-induced VF.     

Antiarrhythmic and electrophysiologic actions of clofilium in experimental canine models

Clofilium was studied in three experimental models. In non-ischemic and chronically infarcted canine hearts, clofilium (0.5-2 mg/kg) produced a dose-dependent increase in electrical ventricular fibrillation threshold (VFT), but prolonged the effective refractory period (ERP) of normal myocardium in only the non-ischemic heart. When chronically infarcted hearts were subjected to programmed electrical stimulation, 1 mg/kg of clofilium inhibited the re-induction of either ventricular tachycardia or ventricular fibrillation in 5 of 6 animals and slowed the rate of the induced tachycardia in the sixth. Clofilium, however, failed to alter ventricular refractory periods of normal myocardium at either twice diastolic threshold current (176 +/- 5 ms control vs. 187 +/- 9 ms post-clofilium, P greater than 0.05) or at 10 mA (134 +/- 6 ms control vs. 137 +/- 13 ms post-clofilium, P greater than 0.05). In addition, chronic administration of clofilium (2 mg/kg, i.v., followed by 1 mg/kg every 12 h) was ineffective in decreasing mortality in a canine model of sudden coronary death. Of 10 saline-treated conscious animals subjected to an electrically-induced intimal lesion of the left circumflex coronary artery in the presence of a previous ischemic insult, all 10 died suddenly of ventricular fibrillation within 173 +/- 45 min after current application. Under similar conditions, 7 clofilium-treated animals died suddenly within 249 +/- 88 min (P greater than 0.05) after current application while 3 animals survived (P greater than 0.10). Clofilium did, however, elevate the effective refractory period in these animals (150 +/- 3 ms saline-treated vs. 195 +/- 7 ms clofilium-treated). It is concluded from our data that there is little relationship between clofilium's electrophysiologic actions in normal myocardium and antiarrhythmic effects. Furthermore, simple prolongation of refractoriness in normal non-ischemic myocardium may be insufficient for the prevention of ventricular fibrillation which develops in response to a transient ischemic event superimposed on a chronically injured myocardium.     

急性缺血对犬在体左心室内膜恢复性质的影响

目的探讨急性缺血对左心室内膜整体恢复性质的影响。方法健康犬10只,应用非接触球囊标测技术,同步记录在体阻断左前降支30 min前后心内膜各区域单极电图,测量激动恢复间期(ARI)和舒张间期(DI),计算恢复曲线斜率。结果正常供血状态下心肌内膜恢复曲线存在一定差异。从心尖部向心底部,曲线的斜率呈逐步下降的趋势,左心室内膜恢复曲线的斜率总体上<1。急性缺血后,缺血区恢复曲线变平;而在部分非缺血区(室间隔后部接近心底部及心室流出道附近)恢复曲线变陡峭,斜率显著升高,最大的曲线斜率>1,与缺血前比较差异有统计学意义(P<0.05)。结论急性缺血后,缺血与非缺血心肌的恢复性质均发生改变,部分非缺血心肌恢复曲线斜率显著增加。     

Effect of a novel thromboxane A2 synthetase inhibitor on ischemia-induced mitochondrial dysfunction in canine hearts

This study was designed to determine the effect of sodium 6-(2-[1-(1H)-imidazolyl]methyl-4,5-dihydrobenzo[b] thiophene)carboxylate (RS-5186), a new thromboxane A2 (TXA2) synthetase inhibitor, on mitochondrial function and lysosomal integrity in ischemic myocardium. 17 anesthetized mongrel dogs were divided into 2 groups. In the control group (n = 11), the left anterior descending arteries (LAD) of the dogs were occluded for 2 h and physiological saline was infused until the end of the experiment. In the RS-5186 treated group (n = 6), 25 min prior to LAD occlusion, RS-5186, 10 mg/kg, was injected for 10 min. 2 h after occlusion, mitochondria were prepared from both ischemic and non-ischemic areas, which were confirmed by Evans' blue dye, and mitochondrial function (respiratory control index: RCI, and the rate of oxygen consumption in state III respiration: St.III O2) was measured polarographically with succinate as substrate. Fractionation of myocardial tissue from both ischemic and non-ischemic areas was also performed, and the activities of lysosomal enzymes (N-acetyl-beta-glucosaminidase: NAG, beta-glucuronidase: beta-gluc) of each fraction were measured. 2-h LAD occlusion induced a significant greater decrease in mitochondrial function from the ischemic area of the control group (RCI: 2.80 +/- 0.45, St.III O2: 133.5 +/- 35.6 natoms/mg protein/min) compared with those from the non-ischemic area (RCI: 4.49 +/- 0.46, St.III O2: 344.0 +/- 31.9).(ABSTRACT TRUNCATED AT 250 WORDS)     

The effect of cibenzoline on myocardial damages in dogs

The antiarrhythmic and cardioprotective effects of cibenzoline (4,5-dihydro-2-(2,2-diphenylcyclopropyl)-1H-imidazole) were investigated. Nineteen adult mongrel dogs were divided into 2 groups; in the control group, physiological saline (25 ml) was administered, and 20 min after, the left anterior descending coronary artery (LAD) was occluded for 2 h; in the cibenzoline group, cibenzoline (2 mg/kg), was administered 10 min before 2 h LAD occlusion. Blood pressure and appearance of arrhythmias were monitored throughout the experiment. Two h after occlusion, mitochondria were prepared from both ischemic and non-ischemic areas in each group, and their functions were measured polarographically. Fractionation of myocardial tissue from both ischemic and non-ischemic areas was performed, and activities of lysosomal enzymes (N-acetyl-beta-glucosaminidase and beta-glucuronidase) were measured in each fraction. Administration of cibenzoline significantly reduced the appearance of ventricular arrhythmias in association with ischemia. Cibenzoline did not change significantly blood pressure and heart rate. In the control group, mitochondrial dysfunction and leakage of lysosomal enzymes induced by 2 h occlusion were observed. Administration of cibenzoline maintained significantly mitochondrial function and prevented significantly leakage of lysosomal enzymes. These results indicated that cibenzoline has a cardioprotective as well as an antiarrhythmic effect on ischemic myocardium.