Antiarrhythmic efficacy of CPUY102122, a multiple ion channel blocker,on rabbits with ischemia/reperfusion injury

BackgroundThe antiarrhythmic potential of a novel multichannel blocker CPUY102122 (CY22) was investigated in the present study.MethodsThe effect of CY22 on rapid delayed rectifier potassium channel current (I_Kr) was studied using whole-cell patch clamp techniques in Chinese Hamster Ovary cells stably expressing human Ether-à-go-go-Related Gene. We further evaluated the antioxidant effects of CY22 and demonstrated the reversal of connexin down-regulation in the development of cardiac ventricular arrhythmias, which was produced using coronary ligation/reperfusion in rabbits. CY22 and Amiodarone were administered 30 min prior to the procedure. Next, electrocardiograms were recorded, protein expression of left ventricular Connexin43 (Cx43), non-phosphorylation-Cx43 (np-Cx43), Rac-1 and gp-91[phox] were assayed using Western blot analysis, microstructural changes in the myocardium were observed and redox system activity was assayed.ResultsCY22 inhibited I_Kr in a concentration-dependent manner with IC₅₀ value of 2.8 ± 0.8 μmol/L. CY22 treatment significantly decreased T-wave amplitude and QTc arrhythmic scores and ameliorated the shape of the infarcted myocardium compared to the model group. CY22 decreased the serum levels of creatine kinase, lactate dehydrogenase, and myocardial levels of malondialdehyde, as well as increased superoxide dismutase activity. Cx43 expression in the left ventricle was significantly increased by CY22 treatment, which significantly decreased np-43 expression, Rac-1 activity and gp-91[phox] protein expression.ConclusionsThese results indicated that CY22 has both antiarrhythmic and cardiovascular protective effects partly by blocking I_Kr, the production of antioxidants and protection of Cx43.     

Influence of ATP-sensitive potassium channel blocker on hypoxia-induced damage of isolated guinea pig heart.

1. Isolated guinea pig hearts were perfused under constant flow conditions with Krebs-Henseleit buffer. Hearts were subjected to 15 min of hypoxia followed by reoxygenation in the presence and in the absence of 100 microns glyburide, an ATP-sensitive potassium channel blocker. Heart rate, left ventricular pressure and lactate dehydrogenase (LDH) release were measured at 5 min intervals. 2. Small decreases in heart rate and left ventricular pressure were observed during glyburide infusion with hypoxia, however LDH release, which was used as an index of cellular damage, was dramatically elevated. 3. Neither glyburide, nor the vehicle in which it was dissolved, appeared to produce myocardial damage under normoxic conditions. 4. It is concluded that ATP-sensitive potassium channels are important in the protection of the myocardium during hypoxia in isolated guinea pig hearts perfused under constant flow conditions.     

An ATP-sensitive potassium channel blocker abolishes the potentiating effect of morphine on the bicuculline-induced convulsion in mice

ICV bicuculline, a selective GABA_A antagonist, dose-dependently induced clonic-tonic convulsions in mice. Coadministration of ICV morphine ( opioid agonist) significantly potentiated ICV bicuculline-induced convulsions, and this effect of morphine was completely blocked by pretreatment with-funaltrexamine (-FNA), a antagonist. ICV glibenclamide, a selective ATP-sensitive potassium (K_ATP) channel blocker, at a dose which alone did not affect the convulsive threshold of bicuculline, was capable of blocking the exacerbation of ICV bicuculline-induced convulsions by morphine. The present data further suggest that K_ATP channels may play a tonic regulatory role in the potentiative effect of morphine on ICV bicuculline-induced convulsions.     

Effective pharmacotherapy against oxidative injury: alternative utility of an ATP-sensitive potassium channel opener

Cardiomyocyte viability following ischemia-reperfusion critically depends on mitochondrial function. In this regard, potassium channel openers (KCOs) targeting mitochondria have emerged as powerful cardioprotective agents when applied at the onset of ischemia. However, it is controversial whether openers are still protective when applied at the onset of reoxygenation. Here, H9c2 cardiomyocytes and mitochondria isolated from the rat heart ventricle were subjected to ischemia-reoxygenation or oxidative stress in the absence or presence of 100 microM diazoxide, a potassium channel opener. Ischemia-reoxygenation or oxidative stress significantly reduced cell viability, induced structural damage in association with increased mitochondrial protein release, and impaired oxidative phosphorylation. However, treatment with diazoxide before anoxia or at the onset of reoxygenation, as well as during oxidative stress, prevented cell death and mitochondrial dysfunction and preserved cellular and mitochondrial structural integrity. These protective effects were blocked by 5-hydroxydecanoate. Thus, treatment with potassium channel openers even at the time of reoxygenation may provide a significant protection of the myocardium. The protective mechanism is at least in part endogenous to the mitochondria because protection was also observed in isolated mitochondria.     

Effects of several potassium channel openers and glibenclamide on the uterus of the rat.

1. The ability of several potassium (K+) channel openers to inhibit spasm of the uterus of the nonpregnant rat and their susceptibility to antagonism by glibenclamide was assessed in vitro and in vivo. 2. In the isolated uterus exposed to oxytocin (0.2 nM), cromakalim, RP 49356 and pinacidil were of similar potency (mean pD2 = 6.4, 6.0 and 6.2 respectively) while minoxidil sulphate was of lower potency (pD2 = 4.7). Glibenclamide antagonized cromakalim and RP 49356 with the interactions consistent with competitive antagonism (mean pA2 of 6.57 and 7.00 respectively). Glibenclamide also antagonized pinacidil (pA2 = 6.22) but the slope of the Schild plot was significantly greater than -1. Neither salbutamol nor minoxidil sulphate was antagonized by glibenclamide (10 microM). 3. Cromakalim (1 and 10 microM), RP 49356 (1 and 10 microM), pinacidil (1 microM) and minoxidil sulphate (100 microM) suppressed spasm evoked by low (less than 40 mM) but not high (greater than or equal to 40 mM) KCl concentrations. Glibenclamide (10 microM) prevented cromakalim (10 microM)-, RP 49356 (10 microM)- and pinacidil (10 microM)-induced suppression of KCl (20 mM)-evoked spasm. Pinacidil (10 and 100 microM), cromakalim (100 microM) and salbutamol (0.01-1 microM) inhibited spasm evoked by all concentrations of KCl (10-80 mM). Suppression of spasm evoked by KCl (10-80 mM) by cromakalim (100 microM) and pinacidil (100 microM) was insensitive to glibenclamide (10 microM). 4. Cromakalim (0.1 mg kg-1) and RP 49356 (0.1 mg kg-1), given by i.v. bolus injection, inhibited uterine contractions, produced a fall in blood pressure and a slight tachycardia in the conscious ovariectomized rat.(ABSTRACT TRUNCATED AT 250 WORDS)     

丹参素对大鼠心室肌动作电位、L-型钙电流和ATP敏感性钾电流的作用

目的研究丹参素对单个大鼠心室肌细胞动作电位、L-型钙电流和ATP敏感性钾电流（IKAVP）的影响,探讨丹参素在离子通道水平的药理机制。方法胶原酶急性酶解法分离单个大鼠心室肌细胞,采用全细胞膜片钳的方法,记录丹参素对动作电位、L-型钙电流和IKATP的影响。结果丹参素可影响心室肌细胞动作电位时程（APD）,并能使APD25、APD50和APD90显著缩短;丹参素能够抑制三．型钙电流;丹参素可使IKA卯外向电流增大,此效应呈浓度依赖性。结论丹参素的心肌保护作用机制与抑制L-型钙电流和部分激活IKA口外向电流有关。     

Neuroprotective effect of gadolinium: a stretch-activated calcium channel blocker in mouse model of ischemia–reperfusion injury

The present study was designed to investigate the potential of gadolinium, a stretch-activated calcium channel blocker in ischemic reperfusion (I/R)-induced brain injury in mice. Bilateral carotid artery occlusion of 12 min followed by reperfusion for 24 h was given to induce cerebral injury in male Swiss mice. Cerebral infarct size was measured using triphenyltetrazolium chloride staining. Memory was assessed using Morris water maze test and motor incoordination was evaluated using rota-rod, lateral push, and inclined beam walking tests. In addition, total calcium, thiobarbituric acid reactive substance (TBARS), reduced glutathione (GSH), and acetylcholinesterase (AChE) activity were also estimated in brain tissue. I/R injury produced a significant increase in cerebral infarct size. A significant loss of memory along with impairment of motor performance was also noted. Furthermore, I/R injury also produced a significant increase in levels of TBARS, total calcium, AChE activity, and a decrease in GSH levels. Pretreatment of gadolinium significantly attenuated I/R-induced infarct size, behavioral and biochemical changes. On the basis of the present findings, we can suggest that opening of stretch-activated calcium channel may play a critical role in ischemic reperfusion-induced brain injury and that gadolinium has neuroprotective potential in I/R-induced injury.     

ATP敏感性钾通道开放剂埃他卡林对高原脱习服的影响

目的：观察长期口服埃他卡林对高原脱习服的影响。方法：该临床研究采用随机双盲安慰剂平行对照试验方法,随机分为埃他卡林试验组和安慰剂对照组,两组受试者分别为39例和17例。其中,受试者分别口服埃他卡林片（5mg／片,1次／日）或安慰剂（1片／日）,连续服用药物7个月,下山到3700m停留2d并停止服药,再返回到海拔1400m的平原地区,自返回平原的第2、4、6天,进行高原脱习服症状调查,随访受试者的高原脱习服症状并进行症状评分。结果：长期驻扎在5200～5380m高海拔地区的受试者,返回平原后第2、4、6天,分别有82．4％、52．9％、23．5％的人员产生显著的高原脱习服症状,长期口服埃他卡林,高原脱习服发生率分别为43．6％、30．8％、38．5％;安慰剂对照组返回平原后脱习服反应程度的评分,在第2、4、6天分别为（6．0±1．9）、（4．6土1．0）、（3．8±1．5）分,埃他卡林治疗组分别为（4．4±2．4）、（3．3±1．8）、（4．0±1．5）分,两组比较,在返回低海拔第2、4天,高原脱习服反应的发病率及发病程度均显著减少,第6天的数据两组之间差别无统计学意义。结论：高原地区长期口服埃他卡林可显著减轻高原脱习服的发病程度,降低高原脱习服的发生率,预防高原脱习服。     

心肌线粒体ATP敏感性钾通道开放保护线粒体结构和功能

目的　评价线粒体ATP敏感性钾通道 (mitoKATP)开放剂二氮嗪对缺氧心肌线粒体结构和功能的影响。方法　异丙肾上腺素 (ISO)皮下注射诱发大鼠心肌缺氧损伤 ,观察二氮嗪对线粒体呼吸控制比 (RCR)、膜流动性、磷脂酶A2 和磷脂含量的影响。结果　ISO皮下注射诱发大鼠心肌缺氧损伤后 ,与对照组比较线粒体RCR降低了 2 0 8% (P <0 0 1) ,膜流动性降低了 9 1% (P <0 0 5 ) ,磷脂酶A2 活性增加了14 4 5 % (P <0 0 1) ,磷脂含量下降了 37 5 % (P <0 0 5 ) ,二氮嗪预防性给药后可改善RCR、膜流动性和磷脂含量。结论　二氮嗪可保护心肌缺氧损伤后线粒体膜结构和功能的完整     

Melatonin alleviates intestinal injury,neuroinflammation and cognitive dysfunction caused by intestinal ischemia/reperfusion

Intestinal ischemia/reperfusion (I/R) can cause multiple organ damage with extremely high morbidity and mortality. Melatonin has anti-inflammatory, anti-oxidative and anti-apoptotic effects against various diseases. This study aimed to explore whether melatonin had a protective effect against intestinal I/R-induced neuroinflammation and cognitive dysfunction, and investigate its potential mechanisms. In this study, melatonin was administered to the rats with intestinal I/R, then histological changes in intestine and brain (frontal cortex and hippocampal CA1 area) tissues and cognitive function were detected, respectively. The encephaledema and blood–brain barrier (BBB) permeability were observed. Moreover, the alterations of proinflammatory factors (tumor necrosis factor-α, interleukin-6 and interleukin-1β), oxidative response (malondialdehyde, superoxide dismutase, and reactive oxygen species), apoptosis and proteins associated with inflammation, including Toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (Myd88) and phosphorylated nuclear factor kappa beta (NF-κB), and apoptosis (cleaved caspase-3) in brain tissues were examined. Furthermore, the expressions of TLR4, Myd88, and microglial activity were observed by multiple immunofluorescence staining. The results showed that intestinal I/R-induced abnormal neurobehavior and cerebral damage were ameliorated after melatonin treatment, which were demonstrated by improved cognitive dysfunction and aggravated histology. Furthermore, melatonin decreased the levels of proinflammatory factors and oxidative stress in plasma, intestine and brain tissues, attenuated apoptotic cell, and inhibited the expressions of related proteins and the immunoreactivity of TLR4 or Myd88 in microglia in brain tissues. These findings showed that melatonin might relieve neuroinflammation and cognitive dysfunction caused by intestinal I/R, which could be, at least partially, related to the inhibition of the TLR4/Myd88 signaling in microglia.     

褪黑素对肠缺血再灌注损伤保护作用的临床研究

目的 研究褪黑素对肠缺血再灌注损伤(IIRI)的保护作用.方法 研究对象随机分为缺血再灌注A组,生理盐水处理B组,地塞米松治疗C组,褪黑素治疗D组,每组20例.手术解除肠缺血前后10min分别静脉注射生理盐水10ml、地塞米松20mg和褪黑素20μg,手术结束后1h内采外周静脉血,用MDA、SOD试剂盒测定血浆MDA浓度和SOD活性.用NO试剂盒和酶学分光光度法测定血浆NO2-/NO3-水平和血浆D-乳酸水平.观察处理后各组肠管颜色完全恢复时间和术后肛门排气时间.结果 褪黑素治疗组与生理盐水处理组和地塞米松治疗组比较,血浆SOD活性明显上升(P＜0.01),MDA浓度降低(P＜0.05),血浆中NO2-/NO3-浓度上升(P＜0.05),D-乳酸明显降低(P＜0.01),各组肠管颜色完全恢复时间和术后肛门排气时间均有缩短(P＜0.05).结论 褪黑素对肠缺血再灌注损伤有较好保护作用,其机制可能是通过清除氧自由基,防止脂质过氧化和保护肠黏膜机械屏障.     

Fluorescence microscopy studies with a fluorescent glibenclamide derivative, a high-affinity blocker of pancreatic beta-cell ATP-sensitive K+ currents

Hypoglycemic sulfonylureas (e.g. tolbutamide, glibenclamide) exert their stimulatory effects on pancreatic beta-cells by closure of ATP-sensitive K(+) (K(ATP)) channels. Pancreatic K(ATP) channels are composed of two subunits, a pore-forming inwardly rectifying K(+) channel (Kir6.2) subunit and a regulatory subunit (the sulfonylurea receptor of subtype 1 (SUR1)) in a (SUR1/Kir6.2)(4) stoichiometry. The aim of the present study was to characterize the interaction of green-fluorescent 3-[3-(4,4 difluoro-5,7-dimethyl-4-bora-3a,4a-diaza-S-indacen-3-yl)propanamido] glibenclamide (Bodipy-glibenclamide) with pancreatic beta-cell K(ATP) channels using patch-clamp and fluorescence microscopy techniques. Bodipy-glibenclamide inhibited K(ATP) currents from the clonal insulinoma cell line RINm5F half-maximally at a concentration of 0.6nM. Using laser-scanning confocal microscopy Bodipy-glibenclamide was shown to induce a diffuse fluorescence across the RINm5F cell, but only about 17% of total Bodipy-glibenclamide-induced fluorescence intensity in RINm5F cells was due to specific binding to SUR1. Using fluorescence correlation spectroscopy, it could be demonstrated that the fluorescence label contributes to the protein binding and, therefore, possibly also to the non-specific binding of Bodipy-glibenclamide observed in RINm5F cells. Specific binding of Bodipy-glibenclamide to SUR1 in RINm5F cells might be localized to different intracellular structures (nuclear envelope, endoplasmic reticulum, Golgi compartment, insulin secretory granules) as well as to the plasma membrane. In conclusion, Bodipy-glibenclamide is a high-affinity blocker of pancreatic beta-cell K(ATP) currents and can be used for visualizing SUR1 in intact pancreatic beta-cells, although non-specific binding must be taken into account in confocal microscopy experiments on intact beta-cells.     

三磷酸腺苷敏感性钾通道开放剂与心肌再灌注损伤

心肌缺血再灌注损伤与缺血诱发膜除极、电解质及电生理紊乱、能量代谢障碍、细胞内钙超负荷和自由基损伤有关。三磷酸腺苷 (adenosinetriphosphate ,ATP)敏感性钾通道活化 ,可使膜超极化 ,恢复紊乱的电解质 (主要是K+ 离子 )及电生理平衡 ,降低能耗 ,减轻钙超载和自由基损伤而具有心肌保护作用。     

三碘甲状腺原氨酸及格列本脲对缺血再灌注损伤后未成熟心肌细胞凋亡的影响

目的通过三碘甲状腺原氨酸(T3)对缺血再灌注损伤后未成熟心肌细胞凋亡的影响,探讨其作用机制。方法培养原代乳鼠未成熟心肌细胞,通过在缺氧复氧前给予T3或(和)格列本脲处理,用TUNEL检测法检测正常组、缺氧复氧处理组以及在缺氧复氧前给予T3或(和)格列本脲干预后心肌细胞凋亡情况。结果缺氧复氧前短期给予T3可减少心肌细胞凋亡,而这种保护作用可被格列本脲阻断。结论 T3可以对抗缺血再灌注对心肌细胞损伤的能力,而对心肌细胞凋亡这种保护作用与KATP通道相关。     

线粒体ATP敏感性钾通道不参与异丙酚预处理的心肌保护

目的　观察异丙酚预处理对心肌缺血再灌注损伤的保护机制是否通过开放线粒体ATP敏感性K通道 (KATP)。方法　非循环式Langendorff离体心脏灌注模型 ,灌注 1h ,常温下行全心缺血 2 5min ,恢复再灌注 30min。通过Maclab仪记录左室舒张末压 (LVEDP)、左室发展压 (LVDP)、左室压上升和下降最大速率 (±dp/dtmax)。测恢复再灌注末心肌组织MDA含量。结果　恢复再灌注 30min末 ,对照组(Con)、异丙酚预处理组 (PP)、5 HD +PP和 5 HD组心肌组织的MDA含量分别为 (113 7± 2 0 9)、(89 4± 13 7)、(91 9± 14 4 )和 (114 8± 19 7)nmol·10 0mg-1。PP组和 5 HD+PP组的心肌MDA含量都明显低于Con组和 5 HD组 (P<0 0 5 ) ;PP组和 5 HD +PP组两组间的MDA差异无显著性 (P >0 0 5 )。恢复再灌注 30min末 ,Con组、PP组、5 HD+PP组和 5 HD组的LVEDP值分别为基础值的 5 1、3 2、3 6和 5 3倍。PP组和 5 HD +PP组LVEDP值的上升幅度均明显低于Con组和 5 HD组 (P <0 0 5 ) ,而 5 HD +PP组和PP组之间差异无显著性 (P >0 0 5 )。结论　异丙酚预处理的心肌保护不是通过开放线粒体ATP敏感性K通道 ,其心肌保护作用和线粒体KATP无关     

茶多酚对大鼠肠缺血再灌注肠损伤的保护作用

目的:研究茶多酚(TP)对大鼠肠缺血再灌注(I/R)所致肠损伤的保护作用及其可能的作用机制,为其临床新用途提供实验依据。方法:大鼠随机分为肠I/R损伤对照组、假手术组及TP给药组(100,50,25和12.5 mg.kg-1),通过夹闭肠系膜上动脉1 h、再灌注2 h,建立肠I/R损伤模型。于缺血前20 m in舌下静脉注射药物,假手术组仅分离、不夹闭肠系膜上动脉。再灌2 h后,各组取血及中段小肠组织,测定血清及小肠组织中超氧化物歧化酶(SOD)、丙二醛(MDA)和一氧化氮(NO)含量,光镜下观察小肠组织形态学改变。结果:与假手术组相比,肠I/R损伤对照组血清及小肠组织中的SOD活力降低,MDA和NO含量升高,镜检发现小肠有明显组织形态学损伤。与肠I/R损伤对照组相比,TP组呈剂量依赖性增强SOD活力,减少MDA及NO含量,减轻小肠组织形态学损伤。结论:TP对肠I/R所致肠急性损伤有显著的及剂量依赖性的保护作用,可能与其自由基清除作用有关。     

Effects of sasanquasaponin on ischemia and reperfusion injury in mouse hearts

We investigated effects of sasanquasaponin (SQS), a traditional Chinese herb's effective component, on ischemia and reperfusion injury in mouse hearts and the possible role of intracellular Cl- homeostasis on SQS's protective effects during ischemia and reperfusion. An in vivo experimental ischemia model was made in mice (weight 27-45 g) using ligation of left anterior descending coronary artery, and in vitro models were made in perfused hearts by stopping flow or in isolated ventricular myocytes by hypoxia. The in vivo results showed that SQS inhibited cardiac arrhythmias during ischemia and reperfusion. Incidence of arrhythmias during ischemia and reperfusion, including ventricular premature beats and ventricular fibrillation, was significantly decreased in the SQS-pretreated group (P<0.05). Results in perfused hearts showed that SQS suppressed the arrhythmias, prevented against ischemia-induced decrease in contract force and promoted the force recovery from reperfusion. Furthermore, intracellular Cl- concentrations ([Cl-]i) were measured using a MQAE fluorescence method in isolated ventricular myocytes in vitro. SQS slightly decreased [Cl-]i in non-hypoxic myocytes and delayed the hypoxia/reoxygenation-induced increase in [Cl-]i during ischemia and reperfusion (P<0.05). Our results showed that SQS protected against ischemia/reperfusion-induced cardiac injury in mouse hearts and that modulation of intracellular Cl- homeostasis by SQS would play a role in its anti-arrhythmia effects during ischemia and reperfusion.     

Multiple actions of U-37883A, an ATP-sensitive K+ channel blocker, on membrane currents in pig urethra

The effects of U-37883A, a vascular ATP-sensitive K(+) channel (K(ATP) channel) blocker, on membrane currents were investigated in pig urethral myocytes by use of patch-clamp techniques (conventional whole-cell recordings, nystatin-perforated patches and cell-attached configuration). Tension measurement was also performed to study the effects of U-37883A on the levcromakalim-induced urethral relaxation and the urethral resting tone in the absence and presence of Bay K 8644. Although cumulative application of U-37883A produced a concentration-dependent inhibitory effect on the levcromakalim-induced urethral relaxation, U-37883A did not abolish the relaxation. In nystatin-perforated patch recording, K(ATP) currents activated by levcromakalim were inhibited by U-37883A in a concentration-dependent manner (K(i), 4.7 microM). Approximately 10% of the K(ATP) currents still remained even in the presence of 300 microM U-37883A. In cell-attached mode, extracellular application of U-37883A (100 microM) irreversibly inhibited the activity of the levcromakalim-induced K(ATP) channels. In whole-cell configuration, U-37883A suppressed the peak amplitude of voltage-dependent Ba(2+) currents in a concentration- and voltage-dependent manner, and at 30 microM, shifted the steady-state inactivation curve of the Ba(2+) currents to the left at -90 mV. These results demonstrate that U-37883A reduces not only the activities of K(ATP) channels but also voltage-dependent Ca(2+) channels. Therefore, it is not appropriate to define U-37883A as solely a vascular K(ATP) channel blocker.     

氯沙坦对大鼠心肌缺血再灌注损伤的影响

目的:观察血管紧张肽II1型受体阻断剂 氯沙坦对大鼠缺血再灌注心肌的梗死面积、心肌结 构、肿瘤坏死因子α(TNF α)、白细胞介素6(IL 6) 的影响。方法:雄性Sprague Dawley(SD)大鼠42只 随机分为4组:对照组、缺血再灌注组、氯沙坦 5mg·kg-1组和氯沙坦10mg·kg-1组。除对照组 外,余3组建立心肌缺血再灌注模型,2个氯沙坦组 分别于缺血前15min静脉注射氯沙坦5,10mg· kg-1。计算心肌梗死范围,观察心肌细胞超微结构, 检测再灌注后血浆TNF α和IL 6的浓度。结果:与 缺血再灌注组相比,2氯沙坦组梗死面积减小(P< 0.01),心肌超微结构改善。缺血再灌注组TNF α 和IL 6的浓度均明显高于对照组(P<0.01);2个 氯沙坦组TNF α和IL 6的浓度均低于缺血再灌注 组(P<0.01),其中氯沙坦10mg·kg-1组较 5mg·kg-1组的浓度低(P<0.05,P<0.01)。结 论:氯沙坦具有抗大鼠心肌缺血再灌注损伤的作用, 高剂量氯沙坦的效果明显,其机制可能与从受体水 平阻断肾素 血管紧张肽系统,减少炎性因子TNF α和IL 6的产生有关。