急性高血糖对大鼠脑缺血再灌注损伤的影响

目的探讨急性高血糖对大鼠脑缺血再灌注损伤的影响,并分析高血糖浓度与脑缺血再灌注损伤程度及预后关系。方法制备SD大鼠大脑中动脉缺血再灌注模型,于术前30 min腹腔注射25%葡萄糖或生理盐水(10 mL/kg体重),缺血90 min,再灌注24 h后评估大鼠神经缺失症状,检测血清肌酸激酶脑型同工酶水平、脑梗死体积、脑组织含水量,以及神经细胞凋亡和脑组织病理形态学改变。结果与模型组相比,高血糖组大鼠急性期存活率降低(P<0.05),脑组织病理损害明显加重,脑梗死体积、细胞凋亡数、脑组织含水量、颅底出血风险、神经缺失症状及血清肌酸激酶脑型同工酶水平均显著升高(P<0.05或P<0.01)。大鼠血清肌酸激酶脑型同工酶水平与缺血再灌注前血糖浓度有直线相关关系(r=0.68)。结论通过扩大脑梗死体积,促进细胞凋亡,增加脑组织含水量和血清肌酸激酶脑型同工酶水平,急性高血糖加重大鼠脑缺血再灌注损伤。高血糖浓度与脑缺血再灌注损伤程度有直线相关关系,对预后不利。     

复方仙灵脾注射液对大鼠脑缺血再灌注损伤作用的实验研究

目的：探讨复方仙灵脾注射液（FFXLPI）对脑缺血再灌注损伤的保护作用。方法：采用大鼠全脑缺血再灌注损伤模型，观察脑缺血前后血浆NO、ET和脑组织钙及含水量的变化。结果：脑缺血再灌注期血浆NO、ET和脑组织钙及含水量显著升高（P＜0．05－0．01），使用复方仙灵脾注射液后，血浆NO、ET和脑组织钙及含水量明显降低。结论：FFXLPI对脑缺血再灌注损伤确有保护作用。     

胸腺素β4对大鼠局灶性脑缺血再灌注损伤后血脑屏障的影响

目的：观察胸腺素β4对大鼠局灶性脑缺血再灌注损伤后血脑屏障的影响,并探讨其作用机制。方法将72只SD大鼠随机分为假手术组、对照组、胸腺素β4组各24只。采用线栓法制作大鼠大脑中动脉闭塞局灶性脑缺血再灌注模型,再灌注24 h后,采用干湿重法测定缺血脑组织含水量,通过检测伊文蓝渗透到缺血侧脑组织的含量观察血脑屏障的通透性,应用RT-PCR法检测缺血脑组织紧密连接蛋白5（ Claudin-5）和基质金属蛋白酶-9（MMP-9） mRNA表达。结果脑缺血再灌注损伤24 h后,与假手术组比较,对照组缺血侧脑含水量、伊文蓝含量、MMP-9 mRNA表达明显增加,Claudin-5 mRNA表达显著减少（ P均＜0．01）;与对照组比较,胸腺素β4组缺血侧脑组织含水量、缺血侧伊文蓝含量、MMP-9 mRNA明显降低,Claudin-5 mRNA表达明显升高（P均＜0．01）。结论胸腺素β4对大鼠脑缺血再灌注损伤后的血脑屏障具有保护作用,其作用机制可能是通过促进Claudin-5 mRNA表达和抑制MMP-9 mRNA表达实现的。     

补阳还五汤对大鼠脑缺血再灌注损伤后血脑屏障的影响

目的 观察补阳还五汤对大鼠脑缺血再灌注损伤后血脑屏障的影响并探讨其影响机制。方法 48只SD大鼠随机分为3组：①假手术组（n=16）；②对照组（n=16）；③补阳还五汤组（n=16）。线栓法制作大鼠脑缺血再灌注模型，再灌注48h后干湿重法测定缺血脑组织含水量，经股静脉注射伊文思蓝观察血脑屏障的通透性，取缺血脑组织提取总RNA和蛋白质分别应用逆转录聚合酶链反应和Western杂交技术检测基质金属蛋白酶9的转录及表达情况，同时电镜观察血脑屏障的变化。结果 脑缺血再灌注48h，对照组缺血侧脑含水量明显升高，伊文思蓝含量也明显增加，电镜观察发现血脑屏障破坏严重，基质金属蛋白酶9的转录与表达也较假手术组显著增加；而应用补阳还五汤处理的大鼠其缺血脑组织含水量明显减少，缺血侧伊文思蓝含量较对照组也明显降低（P〈0．05），同时电镜观察到血脑屏障的破坏减轻，而基质金属蛋白酶9mRNA和蛋白表达水平也明显低于对照组。结论 对大鼠脑缺血再灌注损伤后的血脑屏障具有保护作用，其作用机制可能是通过抑制基质金属蛋白酶9的转录和表达来实现的。     

康脑液对脑缺血再灌注损伤大鼠血清及脑组织匀浆SOD、MDA、NO的影响

目的 观察康脑液对脑缺血再灌注损伤大鼠血清及脑组织匀浆超氧化物歧化酶(SOD)、丙二醛(MDA)及一氧化氮(NO)含量的影响.方法 将大鼠随机分为分为假手术组,模型组及康脑液干预组.康脑液干预组每日以康脑液灌胃,假手术组以生理盐水灌胃,连续15 d后,用颈动脉引流法复制脑缺血模型,分别测定各组血清、脑组织匀浆中SOD、MDA及NO的含量.结果 康脑液能显著降低脑缺血再灌注损伤大鼠血清及脑组织中MDA及NO的含量,提高SOD的活性.结论 康脑液对脑缺血再灌注损伤有一定的预防和保护作用,机制与抗自由基、抑制脂质过氧化反应等有关.     

松龄血脉康胶囊对脑缺血再灌注损伤的保护作用

目的以大鼠脑缺血再灌流期间神经行为学及生化指标变化评价松龄血脉康对脑缺血再灌注损伤的保护作用。方法大鼠灌胃松龄血脉康30d,采用线栓法造成大鼠局灶性脑缺血再灌流损伤模型。分别进行大鼠神经行为学评判以及脑含水量、缺血区梗死面积、受损侧脑组织超氧化物歧化酶(SOD)、丙二醛(MDA)、一氧化氮(NO)及一氧化氮合酶(eNOS)含量的检测,同时对大鼠血液流变学指标进行相应研究。结果松龄血脉康可明显改善大鼠神经行为学症状,降低脑组织含水量及大脑缺血区梗死面积,明显降低大鼠脑组织MDA含量,增加eNOS含量,减轻脑缺血对脑组织造成的氧化应激损伤,同时对SOD、NO的变化也有一定的改善作用;松龄血脉康还能影响大鼠血液流变学,明显降低血黏度。结论松龄血脉康对线栓法致大鼠局灶性脑缺血再灌注损伤有明显的保护作用。     

丹红注射液对大鼠脑缺血再灌注后损伤的保护作用及机制研究

目的研究丹红注射液对脑缺血再灌注后神经功能恢复及保护作用机制。方法采用改良线拴法制做大脑中动脉缺血2h再灌注模型,随机分为假手术组、缺血再灌注组、缺血再灌注加丹红注射液组,缺血再灌注组及缺血再灌注加丹红注射液组每日尾静脉注射相同剂量的0．9％氯化钠溶液或丹红注射液（100mg／kg）,观察给药7d后各组大鼠神经行为变化、脑梗死体积,并测定脑组织含水量、丙二醛（MDA）、单胺氧化酶（MAO）活性、超氧化物歧化酶（SOD）活性。结果缺血再灌注加丹红注射液组术后7d时神经功能恢复优于缺血再灌注组,脑梗死体积均小于缺血再灌注组,缺血再灌注加丹红注射液组脑含水量低于缺血再灌注组和假手术组,差异有显著性意义（P〈0．05）。缺血再灌注加丹红注射液组能降低脑组织MAO活力、MDA含量,提高SOD活性,同缺血再灌注组相比差异有显著性（P〈0．05）。结论丹红注射液能促进脑缺血后神经功能恢复,减小梗死体积,对大鼠脑缺血再灌注损伤有一定保护作用。     

尼莫通对大鼠急性脑缺血再灌注损伤后缺血半暗带神经元Na+-K+-ATP酶活性影响的研究

目的研究尼莫通对大鼠急性脑缺血再灌注损伤后缺血半暗带神经元Na＋-K＋-ATP活性的影响。方法选取450只雄性Wistar大鼠随机分为3组（对照组、尼莫通组、假手术组）,每组大鼠根据缺血后再灌注不同时间又分为缺血2 h再灌注6 h、24 h、48 h、72 h、7 d五个亚组（30只/亚组）。采用线栓法制备大鼠缺血2 h再灌注模型,仅尼莫通组采用药物进行干预。分别于再灌注6 h、24 h、48 h、72 h及7d断头取脑,观察缺血半暗带脑组织Na＋-K＋-ATP酶活性、脑组织水肿程度、脑梗死范围及神经症状评分的变化。结果三组间和不同时间点之间各项观察指标比较差异均有统计学意义（P〈0.01）;尼莫通组24 h、48 h、72 h各时间点Na＋-K＋-ATP酶活性及脑组织含水量与对照组相应时间点比较差异有统计学意义（P〈0.05）,尼莫通组24 h、48 h、72 h、7 d各时间点脑梗死面积及神经症状评分较对照组相应时间点显著降低,差异有统计学意义（P〈0.05）。对照组大鼠脑缺血半暗带神经元Na＋-K＋-ATP酶活性于6 h开始降低,48 h达最低值,72 h稍有回升,7 d趋于稳定。结论尼莫通对大鼠急性脑缺血再灌注损伤后缺血半暗带神经元具有保护作用,其机制不仅与拮抗Ca2＋超载有关,同时还可能与改善能量代谢有关。     

依达拉奉对脑缺血再灌注大鼠脑组织及血清NO、T—NOS水平的影响实验研究

目的探讨依达拉奉对局灶性脑缺血再灌注损伤的影响。方法采用线栓法制备SD大鼠大脑中动脉缺血再灌注模型，分为假手术组、脑缺血再灌注对照组和依达拉奉治疗组，分别于缺血1h后行再灌注，设再灌注后2、6、12、24h不同时间点，检测脑组织及血清NO、T—NOS浓度。结果对照组再灌注期间NO浓度先下降后升高，T—NOS变化与NO一致；治疗组脑组织及血清NO、T—NOS水平均明显下降，以再灌注6h最明显。结论依达拉奉可降低NO、T—NOS水平，对缺血再灌注脑组织确有保护作用。     

芪菖治瘫口服液对脑缺血再灌注损伤大鼠脑组织NO和NOS的影响

目的观察芪菖治瘫口服液对脑缺血再灌注损伤大鼠脑组织一氧化氮（NO）及其合酶（NOS）的影响.方法利用先后夹闭大鼠双侧颈总动脉、基底动脉的方法制备大鼠脑缺血再灌注损伤模型,测定假手术对照组、模型对照组、给药组大鼠脑组织中NO、NOS的含量.结果与假手术对照组比较,各给药组大鼠脑NO及NOS含量均不同程度降低（P＜0.05或P＜0.01）,但高于模型对照组,且有统计学意义（P＜0.01）.结论芪菖治瘫口服液具有增加脑NO及NOS含量的作用.     

促心肌素1-C端肽干预大鼠心肌缺血再灌注损伤的效果

目的观察不同的促心肌素1-C端肽（cardiotrophin-1 C-terminal peptides，CTIC）对大鼠心肌缺血再灌注损伤后组织损伤程度的影响。方法用结扎，松解大鼠冠状动脉左后降支制作模型。正常组5鼠；缺血与再灌注组6鼠，缺血30min后开始再灌注；缺血与再灌注后干预组8鼠，缺血30min后开始再灌注。并腹腔注射CTIC-100μg／kg；缺血与再灌注前干预组8鼠，腹腔注射CTIC 100μg／kg，7d后进行缺血与再灌注。实验结束前取血检测血浆一氧化氮、血清肌酸激酶和丙二醛。结果缺血与再灌注后，大鼠血一氧化氮降低（q=8．758，P〈0．01），血肌酸激酶（q=14．391，P〈0．01）和丙二醛浓度升高（q=11．015，P〈0．01）；缺血与再灌注后干预，大鼠血浆一氧化氮升高（q=14．197，P〈0．01），清肌酸激酶（q=10．649，P〈0．01）和丙二醛降低（q=6．167，P〈0．01），但仍高于正常组（P〈0．01）；缺血与再灌注前干预，大鼠血浆一氧化氮浓度高于正常组（q=9．595，P〈0．01），但低于后干预组（q=6．147，P〈0．01），血清肌酸激酶（q=6．147，P〈0．01）和丙二醛（q=10．551，P〈0．01）则高于缺血与再灌注组。结论CTIC再灌注早期短期作用能减轻心肌组织损伤及氧化损伤的程度；但使用较长时间后．大鼠对缺血与再灌注的耐受力降低，组织损伤及氧化损伤的程度明显加重。     

Correlation between plasma and hepatic phosphatidylcholine hydroperoxide, energy charge, and total glutathione content in ischemia reperfusion injury of rat liver

BACKGROUND/AIMS: Oxygen-derived free radicals are believed to be responsible for the hepatocellular injury leading to liver failure following ischemia-reperfusion in liver, endotoxemia and many other life-threatening illnesses. This study was designed to investigate the reactive oxygen species interaction in lipid peroxidation, the adenosine and energy charge levels of liver cells, and total glutathione content in ischemic-reperfusion injury of liver in rat. METHODOLOGY: To prevent intestinal congestion during the clamping of vascular structures, subcutaneous transposition of the spleen was done beforehand. Four to six weeks later, after the development of natural portal-systemic shunts, occlusion of the portal vein, hepatic artery and bile duct was performed for different periods; blood and liver samples were taken at different intervals after the release. On the basis of the ischemia-reperfusion time, the rats were divided into the following 9 groups: 30/0, 30/30, 30/60, 60/0, 60/30, 60/60, 90/0, 90/30, and 90/60. The following parameters were measured: total hepatic glutathione content, adenosine values (ATP, ADP, AMP), energy charge, phosphatidylcholine hydroperoxide (PCOOH) concentrations in liver and plasma, and serum transaminases (AST, ALT). Decreased liver glutathione stores (an indicator of increased oxidative stress), increased serum hepatic transaminases (an indicator of hepatocellular injury), and increased PCOOH (an indicator of cellular-membrane lipid peroxidation) were noted. RESULTS: The ATP level and energy charge diminished significantly with the increase in duration of ischemia and reperfusion. A close correlation between the PCOOH levels in plasma and liver was observed. Extreme damage was noted in the 90-minute ischemia with 60-minute reperfusion group. The hepatic total glutathione level was reduced to the lowest level in the 90/60 group and it correlated with the energy charge level, denoting the highest degree of oxidative stress sustained by the liver cells in this group. CONCLUSIONS: These results indicated that prolonged hepatic ischemia with reperfusion produced bursts of oxygen-derived free radicals which overwhelmed the defense mechanisms of the cells, with a resultant decrease in energy charge associated with an increase in membrane lipid peroxidation. These findings not only provide confirmation of previously reported hepatocellular injury by free radicals generated after reperfusion, but they also establish the use of PCOOH analysis in liver and plasma as a sensitive and specific indicator of the injury process in time. The plasma PCOOH level may be a useful indicator of free radical induced hepatic membrane lipid peroxidation during ischemia-reperfusion, and might be employed in clinical studies of the therapeutic effects of drugs in various liver diseases, as well as for determining the prognosis after different kinds of hepatic operations.     

Oxygen free radical scavengers and reperfusion injury in dog lung preserved in cold ischemia.

Oxygen-derived free radicals are now considered important contributors to tissue injury associated with ischemia and reperfusion. The purpose of this study was to determine the influence of oxygen free radical scavengers on reperfusion injury. The left lower lobes of 15 canine lungs were isolated, preserved, and then reperfused for 120 minutes. Three groups of lobes were studied: Group 1 (n = 5), without ischemia, group 2 (n = 5) four hours of cold ischemia in Euro-Collins solution, group 3 (n = 5) four hours cold ischemia+oxygen free radical scavenger glutathione (0.1 nmol/L) given at the moment of perfusion. Extravascular lung water (grams per gram of blood-free dry lobe weight) after reperfusion was 2.82 +/- 0.32, 5.06 +/- 0.45, 4.21 +/- 0.33 for groups 1 through 3 respectively (p less than 0.001 group 1 versus group 2, p less than 0.001 group 2 versus group 3). Lung tissue lipid peroxidation, measured as thiobarbituric acid reactive material was 125 +/- 11, 270 +/- 30, and 185 +/- 17 nmol/g dry lobe weight for groups 1, 2 and 3 respectively (p less than 0.05 group 2 versus 1 and group 3 versus group 2). The data suggest that oxygen free radical scavengers attenuate reperfusion injury.     

Melatonin prevents increases in neural nitric oxide and cyclic GMP production after transient brain ischemia and reperfusion in the Mongolian gerbil (Meriones Unguiculatus)

ABSTRACT: While nitric oxide (NO) has been implicated as a mediator of glutamate excitotoxicity after cerebral ischemia/reperfusion, melatonin has been reported to inhibit brain NO production by suppressing nitric oxide synthase. The purpose of the present studies was to determine the effect of exogenous melatonin administration on NO-induced changes during brain ischemia/reperfusion. Indicators of cerebral cortical and cerebellar NO production [nitrite/nitrate levels and cyclic guanosine monophosphate(cGMP)] were used to estimate neural changes after transient bilateral carotid artery ligation followed by reperfusion in adult Mongolian gerbils ( Meriones unguiculatus ). Results show for the first time that melatonin prevents the increases in NO and cGMP production after transient ischemia/reperfusion in frontal cerebral cortex and cerebellum of Mongolian gerbils. The inhibitory effect of melatonin on NO production and its ability to scavenge free radicals and the peroxynitrite anion may be responsible for the protective effect of melatonin on neuronal structures during transient ischemia followed by reperfusion.     

The relationship between oxygen radical generation and impairment of myocardial energy metabolism following post-ischemic reperfusion

Oxygen radical toxicity has been implicated in the pathogenesis of myocardial reperfusion injury. In the present study we sought to document the existence of a precise temporal relationship between the time course of free radical generation and the time course of alterations of myocardial energy metabolism during early reperfusion. Rabbit hearts perfused within the bore of a 31-Phosphorous NMR spectrometer were subjected to 30 min of total global ischemia at 37 degrees C. At reflow, 12 control hearts received a bolus of normal perfusate and 12 hearts recombinant human superoxide dismutase (h-SOD) as a 60,000 IU bolus followed by a 100 IU/ml infusion for 15 min. Ischemia resulted in similar depletion of tissue ATP and phosphocreatine (PCr) in the two groups. During the first minute of reflow, recovery of PCr was similar in both groups. However, PCr recovery arrested in control hearts after 2 min, at 63% of baseline, and averaged 64 +/- 4% after 45 min of reperfusion. In contrast, h-SOD treated hearts recovered 86.7% of baseline PCr content after 2 min, 102% after 10 min of reperfusion (P less than 0.001), and 93 +/- 6.4% at the end of the 45 min of reflow (P less than 0.01). The time course of free radical formation during reperfusion was assessed by EPR spectroscopy using both the frozen tissue and the spin trapping methodologies. In control hearts, peak generation of oxygen radicals was reached after 20 s of reflow. h-SOD treatment decreased concentrations of the oxygen-centered radicals in myocardial tissue and of the radical-adducts in the coronary effluent by approximately 80%. Thus, in reperfused hearts peak oxygen radical generation is followed by the occurrence of alterations in the recovery of high energy phosphate metabolism. Both events were largely prevented by administration of h-SOD at reflow. These results provide strong support for a link between oxygen free radical generation and post-ischemic reperfusion injury.     

The role of oxygen free radicals and extracellular calcium ions in reperfusion-induced arrhythmias

To examine the role of oxygen free radicals and extracellular calcium ions in reperfusion-induced ventricular arrhythmias, we evaluated the effects of hypoxic reperfusion, oxygen free radical scavengers, allopurinol and hypocalcemic reperfusion on reperfusion-induced ventricular arrhythmias. The hearts of male Sprague-Dawley rats were perfused in the working heart mode. Whole heart ischemia was induced for 15 min and then reperfused. Rats were divided into 5 groups: control group, scavenger group, allopurinol group, hypoxia group and hypocalcemia group. Scavenger, hypoxic and hypocalcemic perfusions were undertaken only during the period of perfusion. The incidence of reperfusion-induced ventricular fibrillation (Vf) was reduced in the scavenger group (100% to 38%) and the hypoxia group (100% to 50%). Spontaneous reversion of Vf to regular sinus rhythm was recognized in the hypoxia and hypocalcemia groups. In conclusion, oxygen free radicals would play an important role in the genesis of the reperfusion arrhythmias, and extracellular calcium concentration would also play an important role in sustaining the reperfusion arrhythmias. Notably, hypoxic reperfusion had protective effects on both processes.     

Studies on the possible role of oxygen-derived free radicals for impairment of protein and energy metabolism in liver ischemia

The role of oxygen-derived free radicals for impaired protein and energy metabolism in ischemia and reperfusion injury to the liver is not known. In the present study, groups of rats received either catalase (20 mg/kg body weight), superoxide dismutase (SOD; 4 mg/kg body weight), or catalase + SOD i.v. 10 min before induction of ischemia in the left and median liver lobes. Control animals received corresponding volumes of solvent. The length of the ischemic period was 60 or 90 min. Protein synthesis was measured in incubated liver slices before induction of ischemia, at the end of the ischemia period, and during 2 h of reperfusion. Tissue concentrations of ATP, ADP, AMP, and hepatic tissue water were determined at the same time points. Protein synthesis and energy level were markedly reduced at the end of ischemia and were restituted during the 2-h reperfusion when the ischemic period was 60 min; they remained depressed during reperfusion when the ischemic period was 90 min. Hepatic tissue water was increased at the end of the ischemic period and remained elevated during reperfusion. There were no significant differences in protein synthesis, energy level or tissue water between catalase- or SOD-treated animals and controls either at the end of a 60- or 90-min ischemic period or during the 2-h reperfusion. The results suggest that oxygen-derived free radicals do not play a major role for impaired protein and energy metabolism in liver ischemia and following reperfusion.     

Postischemic reperfusion injury can be attenuated by oxygen tension control

Oxygen-derived free radicals cause cytotoxic damage during reperfusion after a period of ischemia and the production of these free radicals may be proportionate to oxygen tension (PO2). The present study tested the hypothesis that oxidative damage may be limited by maintaining a more physiologic PO2 following ischemia. An experimental study in Wistar rats were mounted on a Langendorff apparatus was conducted to estimate baseline aortic flow (AF), coronary flow (CF), cardiac output (CO), systolic pressure (SP), heart rate (HR), and the rate-pressure product (RPP: HRxSP). The hearts were divided into 3 groups (n=7, hearts/group): group 1, hypoxic (PO2=300+/-50 mmHg) reperfusion; group 2, middleoxic (PO2=500+/-50 mmHg) reperfusion; and group 3, hyperoxic (PO2=700+/-50 mmHg) reperfusion. Following 30 min of warm ischemia, hearts in all groups were reperfused at each oxygen pressure. The recovery of cardiac function of each heart was measured at the end of reperfusion. Concentrations of lactate (LAC), lactate dehydrogenase (LDH), and creatine kinase (CK) in the coronary perfusate during reperfusion were measured. The recovery rate of CO, SP, and RPP in group 2 were all significantly better than in the other 2 groups. CK leakage in group 2 was significantly lower than in group 3. A clinical study was also conducted during elective coronary artery bypass grafts in 16 consecutive patients who underwent either hyperoxic (n=8, PO2=450-550 mmHg) or more physiologic (n=8, PO2=200-250 mmHg) cardiopulmonary bypass after aortic unclamping. The clinical study assessed CK-MB, LDH, LAC, and malondialdehyde (MDA) in patient blood prior to starting the surgical procedure and at 30 min and 3, 9, and 21 h after unclamping. Cardiac index (CI), central venous pressure, pulmonary capillary wedge pressure, systolic arterial pressure, and the dose of cathecholamines were also measured. Although no significant differences were present in the dose of cathecholamines, the CI in the more physiologic oxygen tension group was significantly higher than in the hyperoxic group at 3 and 6 h after unclamping. The levels of MDA in the more physiologic PO2 group was significantly lower at 30 min after aortic unclamping than in the hyperoxic group. The present results suggest that in the experimental as well as in the clinical study, high PO2 leads to myocardial reperfusion damage; however, maintaining a more physiologic PO2 during reperfusion following ischemia may attenuate reperfusion injury.     

高密度脂蛋白抗动脉粥样硬化功能的丢失与恢复

巨噬细胞在动脉粥样硬化(As)起始、发展的全过程扮演着中心角色,从巨噬细胞脂质积聚和炎症反应入手,寻求某个作用环节进行干预有可能成为非常合适的As治疗靶点。内皮功能失调是As发生的一个重要起始事件,内皮细胞释放的粘附分子如ICAM、VCAM、ELAM及Selectin,介导单核细胞活化并向内膜下募集、分化,巨噬细胞释放的单核细胞趋化蛋白1(MCP-1)及巨噬细胞移动抑制因子(MIF)在单核细胞的移行和分化中发挥重要作用。MIF还可诱导ICAM、....     

Evaluation of free radical and lipid peroxide formation during global ischemia and reperfusion in isolated perfused rat heart

Summary Free radical species have been implicated as important agents involved in myocardial ischemic and reperfusion injuries. In our study, formation of free radicals was measured directly with electron paramagnetic resonance spectroscopy before ischemia, during 10 minutes of global ischemia, and 20 seconds after reperfusion in the rat heart. We also investigated the formation of thiobarbituric acid-reactive material as index of lipoperoxidation induced by free radicals and measured arrhythmias. Production of free radicals takes place during ischemia since the signal intensity with a g value of 2.004 attributed to free radical species was increased by 50% after 10 minutes of global ischemia. In hearts reperfused with oxygenated perfusate for 20 seconds, the signal doubled. These experiments supply evidence that free radicals are generated in isolated rat heart during a short period of global ischemia and reperfusion. However, this increase was not associated with a concomitant increase of lipid peroxides in the myocardium nor with the development of reperfusion arrhythmias.