Preliminary study on the protective effect of electroacupuncture Neiguan acupoint pretreatment on rats with myocardial ischemia-reperfusion injury:role of the miR-214-3p/NCX1 axis

Background:Ischemia-reperfusion can worsen myocardial damage and increase the risk of death.Studies have revealed that ischemic preconditioning provides the best endogenous protection against myocardial ischemia-reperfusion injury(MIRI),and the principle of electroacupuncture(EA)preconditioning is comparable to that of myocardial ischemic preconditioning adaption.Our earlier research demonstrated that EA pretreatment inhibits the expression of calmodulin-dependent protein kinase IIδ(CaMKIIδ),sodium/calcium exchanger 1(NCX1),and cyclophilin D,hence providing protection against MIRI.However,the exact mechanism is still unknown.The expression of NCX1 mRNA is directly regulated by microRNA-214(miR-214).Moreover,it suppresses the levels of CaMKIIδand cyclophilin D.Whether these variables contribute to EA preconditioning to improve MIRI needs to be investigated,though.This study aimed to preliminarily determine whether EA pretreatment ameliorates MIRI by modulating the miR-214-3p/NCX1 axis.Methods:We used a rat MIRI model to investigate the effect of EA pretreatment on MIRI and the expression of miR-214-3p.In addition,adenovirus injection inhibited miR-214-3p expression in the rat MIRI model,and the influence of EA pretreatment towards MIRI was observed in the context of blocked miR-214-3p expression.Both the myocardial histological abnormalities and the alterations in the ST segment of the rat electrocardiogram were analyzed.NCX1 mRNA,cyclophilin D,and CaMKIIδexpression levels were also analyzed.Results:EA pretreatment improved MIRI.In rats with MIRI,EA administration increased miR-214-3p expression while decreasing NCX1 mRNA,cyclophilin D,and CaMKIIδproteins in cardiac tissues.The beneficial effect of EA pretreatment against MIRI was reversed,coupled with elevated levels of NCX1 mRNA,cyclophilin D,and CaMKIIδprotein expression,when an adenovirus injection disrupted the expression of miR-214-3p.Conclusions:Our findings preliminarily show that EA pretreatment inhibits the expression of NCX1 mRNA,cyclophilin D,and CaMKIIδproteins via miR-214-3p,hence exerting MIRI protection.

Ischemic preconditioning produces more powerful anti- inflammatory and cardioprotective effects than limb remote ischemic postconditioning in rats with myocardial ischemia-reperfusion injury

Background Both ischemic preconditioning （IPC） and limb remote ischemic postconditioning （LRIPOC） have been shown to possess significantly different cardioprotective effects against the myocardial ischemia reperfusion injury （IRI）, but no study has compared the anti-inflammatory effects of IPC and LRIPOC during myocardial IRI process. We hypothesized that IPC and LRIPOC would produce different anti-inflammatory effects in an in vivo rat model with myocardial IRI.

Mechanism of the protective effects of noninvasive limbs preconditioning on myocardial ischemia-reperfusion injury

Background This study aimed at assessing the effect of noninvasive limb preconditioning on myocardial infarct size, and determining whether nitric oxide and neurogenic pathway play an important role in the mechanism of acute remote ischemic preconditioning （IPC）.Methods Forty Wistar rats were randomly divided into four experimental groups. In Group I , the rats underwent 30-minute occlusion of the left anterior descending coronary artery, and 120-minute reperfusion. In Group PL, the rats underwent four cycles of 5-minute occlusion and reperfusion of both hind limbs using a tourniquet before the experiment was continued as in Group I. In Group PL-N and Group PL-,, we administered L-nitro-arginine methyl ester （L-NAME） 10 mg/kg or hexamethonium chloride 20 mg,/kg intravenously, 10 minutes before IPC. Infarct size as a percentage of the area at risk was determined by triphenyhetrazolium chloride staining.Results There were no statistically significant differences in mean arterial pressure and heart rate among these groups at any time point during the experiment （ P〉0. 05 ）. The myocardial infarct size （IS） was decreased significantly in Group PL and Group PL-U compared with Group I , and the IS/AAR was 34. 5%± 7.6%, 35.9%±8.6% and58.5%±8.5%, respectively （P〈0.05）. The IS/AAR was 49.1%±6.5% in Group PEN, and there was no significant difference compared with Group I （P〉0. 05 ）.Conclusions Noninvasive limb IPC is effective in protecting the myocardium from ischemia reperfusion injury. Nitric oxide plays an important role in the mechanism of acute remote IPC, in which the neurogenic pathway is not involved.

Role of Beclin 1-dependent Autophagy in Cardioprotection of Ischemic Preconditioning

Emerging evidence indicates that ischemic preconditioning （IPC） induces autophagy which attenuates myocardial ischemia/reperfusion （I/R） injury. However, the precise mechanisms remain com- plex and unclear. The present study was to investigate which autophagy pathway was involved in the cardioprotection induced by IPC, so that we can acquire an attractive treatment way for iscbemic heart disease. Adult male Sprague-Dawley （SD） rats were randomly divided into sham group, I/R group and IPC group. IPC was induced with three cycles of 5 min regional ischemia alternating with 5 m^n reper- fusion in a heart I/R model. Samples were taken from the center of the infracted heart and examined by using the electron microscopy, the terminal deoxynucleotidyl transferase-mediated nick end-labeling （TUNEL） method, Western blotting and co-immunoprecipitation （Co-IP）. A large number of autophagic vacuoles were observed in the cardiomyocytes oflPC group as compared with I/R group. LC3-II forma- tion, an autophagy marker, was up-regulated in IPC group as compared with FR group （P〈0.05）. Moreover, the interaction between Beclin 1 and Bcl-2 was significantly increased in IPC group as com- pared with I/R group （P〈0.01）. It was also found that IPC decreased I/R-induced apoptosis （P〈0.01）. These results suggest that IPC inhibits Beclin 1-dependent excessive autophagy in reperfusion phase and cooperates with anti-apoptosis pathway to diminish the cell death induced by the myocardial I/R injury.

Effects of sevoflurane preconditioning and postconditioning on rat myocardial stunning in ischemic reperfusion injury

Ischemic preconditioning and postconditioning distinctly attenuate ventricular arrhythmia after ischemia without affecting the severity of myocardial stunning. Therefore, we report the effects of sevofiurane preconditioning and postconditioning on stunned myocardium in isolated rat hearts. Isolated rat hearts were underwent 20 min of global ischemia and 40 min of reperfusion. After an equilibration period （20 min）, the hearts in the preconditioning group were exposed to sevoflurane for 5 min and next washout for 5 min before ischemia. Hearts in the sevoflurane postconditioning group underwent equilibration and ischemia, followed immediately by sevoflurane exposure for the first 5 min of reperfusion. The control group received no treatment before and after ischemia. Left ventricular pressure, heart rate, coronary flow, electrocardiogram, and tissue histology were measured as variables of ventricular function and cellular injury, respectively. There was no significant difference in the duration of reperfusion ventricular arrhythmias between control and sevoflurane preconditioning group （P=0.195）. The duration of reperfusion ventricular arrhythmias in the sevoflurane postconditioning group was significantly shorter than that in the other two groups （P〈0.05）. ＋（dPIdt）max in the sevoflurane preconditioning group at 5, 10, 15, 20, and 30 min after reperfusion was significantly higher than that in the control group （P〈0.05）, and there were no significant differences at 40 min after reperfusion among the three groups （P〉0.05）. As expected, for a 20-min general ischemia, infarct size in heart slices determined by 2,3,5-triphenyltetrazolium chloride staining among the groups was not obvious. Sevofiurane postconditioning reduces reperfusion arrhythmias without affecting the severity of myocardial stunning. In contrast, sevoflurane preconditioning has no beneficial effects on reperfusion arrhythmias, but it is in favor of improving ventricular function and recovering myocardial stunning. Sevoflurane preconditioning and postconditioning may be useful for correcting the stunned myocardium.

阿片受体介导电针预适应对心脏的保护作用

目的探讨电针预适应对心肌缺血/再灌注(MI/R)损伤的保护作用,以及阿片受体在其中扮演的角色。方法采用结扎和再灌大鼠左冠状动脉前降支(LAD)的方法建立实验性心肌缺血/再灌注模型。雄性Wistar大鼠随机分为假手术对照(N)组、心肌缺血模型(M)组、心肌缺血模型+电针(EA)组和心肌缺血模型+纳洛酮+电针(EN)组。电针预适应方法是心肌缺血造模前连续3 d给予双侧内关穴电针,每次30 min。观察比较MI/R前电针处理对心电图ST段、心肌缺血面积的影响。实验结束摘取心脏,透射电镜下观察心肌组织线粒体的超微结构变化。结果与N组比较,M组在缺血15、30 min及再灌注10 min时ST段均明显抬高(均P<0.01);与M组比较,EA组ST段抬高幅度明显降低(均P<0.01),而EN组ST段抬高幅度与M组相近,均明显高于EA组(P<0.01)。以梗死区/危险区比值为指标的观察表明,M组梗死区/危险区比值为(54.4±7.5)%,EA组该比值明显低于M组(P<0.01),EN组该比值则与M组相仿,明显高于EA组(P<0.01)。透射电镜结果显示M组线粒体明显肿胀,呈典型空泡样变,嵴断裂;EA组线粒体肿胀程度较轻,嵴排列较整齐;EN组线粒体肿胀,嵴排列紊乱。结论电针预适应可以改善冠状动脉结扎引起的ST段抬高,减轻心肌缺血的程度,减少心肌梗死面积,减轻心肌线粒体超微结构的病理变化,阿片受体阻断剂纳洛酮可以抑制其保护作用。电针内关穴预适应对心肌缺血具有保护作用,阿片受体参与介导电针预适应改善心肌缺血性损害的作用。

电针预处理对心肌缺血再灌注损伤保护作用及机制研究

目的研究电针预处理对心肌缺血再灌注损伤的保护作用与机制。方法 40只雄性SD大鼠分为4组:电针预处理组、电针预处理+AG490组、假手术组、模型组;分别检测缺血再灌注前后心率、左心室收缩末期压力(LVESP)、左心室舒张末期压力(LVEDP)、左心室内压最大和最小变化速率(dp/dt max、dp/dt min),测定和比较各组心肌细胞凋亡指数和高迁移率族蛋白因子(HMGB1)的表达量。结果电针预处理组LVESP[(127.7±22.6)mm Hg]、dp/dt max[(18 715.5±1 747.6)mm Hg/s]、dp/dt min[(7 341.6±1 528.6)mm Hg/s]均高于模型组[(87.2±9.8)mm Hg、(6 836.9±830.1)mm Hg/s、(4 280.3±267.5)mm Hg/s),LVEDP[(21.1±4.7)mm Hg]低于模型组[(31.6±6.9)mm Hg],差异均有统计学意义(t=4.705、3.839、17.62、5.563,均P<0.01)。电针预处理+AG490组LVESP[(93.8±17.9)mm Hg]、dp/dt max[(9 376.3±2 018.9)mm Hg/s]、dp/dt min[(4460.8±656.5)mm Hg/s]均低于电针预处理组,LVEDP[(30.8±6.5)mm Hg]高于电针预处理组,差异均有统计学意义(t=3.457、10.52、4.954、3.678,均P<0.01)。电针预处理组心肌细胞凋亡指数[(9.5±1.6)%]低于电针预处理+AG490组[(23.7±2.5)%],差异有统计学意义(t=14.65,P<0.01)。结论电针预处理可以抑制HMGB1释放从而减轻心肌缺血再灌注损伤。

电针“内关”预处理对缺血再灌注大鼠心肌线粒体呼吸功能的影响

目的：探讨电针＂内关＂预处理对心肌缺血再灌注损伤过程中心肌线粒体的保护作用。方法：本实验选用3月龄Wistar雄性大鼠45只,体重180-220g,编号后按随机数字表分入空白组、模型组、电针预处理组,每组15只。造模采用结扎左冠状动脉前降支,缺血30分钟,再灌注2小时,观察心肌线粒体的呼吸功能及电镜下超微组织的变化。结果：电针预处理组大鼠部分心肌肌丝溶解、断裂,心肌细胞轻微肿胀,轻度空化,线粒体排列稍紊乱,部分线粒体水肿、存在空泡样病变。电针预处理组的大鼠线粒体RCR处于正常水平,明显高于模型组,存在显著性差异（P〈0.01）,但电针预处理组线粒体RCR低于空白组,差异显著（P〈0.01）。结论：电针＂内关＂预处理能改善心肌组织形态学表达,防止心肌组织结构的破坏,修护心肌缺血性损伤,更对线粒体的结构与功能起到了良性的保护作用。

电针内关预处理干预大鼠心肌缺血再灌注损伤的文献分析

目的:系统评价电针内关预处理干预缺血再灌注大鼠心肌损害的有效性。方法:计算机检索中国期刊全文数据库(CNKI)、万方数据库(WanFang Data)、维普数据库(VIP)、中国生物医学文献数据库(CBM)、PubMed、Embase和Cochrane database(CENTRAL)从建库至2020年4月关于电针内关预处理干预大鼠心肌缺血再灌注损伤的随机对照试验,由2位研究者独立进行文献筛选、资料提取和偏倚风险评价,采用Rev-Man5.3软件进行数据合成和统计分析。结果:最终纳入9项研究共计206只大鼠。Meta分析结果显示,电针内关预处理组的心肌梗死面积、再灌注后心电图ST段电位值、血清肌酸激酶同工酶(CK-MB)及乳酸脱氢酶(LDH)的浓度均低于模型组,血清腺苷的释放量高于模型组。结论:电针内关预处理对心肌缺血再灌注损伤大鼠具有预保护作用,可减少心肌缺血再灌注引起的损伤,但纳入研究的方法学质量低,仍需要更多高质量的临床研究进一步探讨。

针刺“内关”预处理对大鼠缺血再灌注心肌的保护作用及机制研究

目的探讨电针"内关"预处理是否通过p38 MAPK信号通路来影响心肌缺血再灌注损伤。方法选用3月龄Wistar雄性大鼠40只,体重(220±23)g,编号后按随机数字表分入对照组(仅穿线,不结扎)、模型组、电针预处理组、电针预处理+SB230580组,每组10只。通过阻断左冠状动脉前降支缺血30min,再灌注120min,检测心肌缺血再灌注损伤后各项心功能指标(舒张末期压力、左室收缩期平均压、短轴缩短率和射血分数),检测心肌组织中活性氧(ROS)含量,超氧化物歧化酶SOD活性,丙二醛(MDA)含量及ATP含量,透射电镜下观察心肌超微结构的变化。结果与对照组比较,模型组各项心功能指标中舒张末期压力升高,左室收缩期平均压、短轴缩短率和射血分数均降低(均P<0.05),梗死面积和梗死程度均升高(均P<0.01),心肌肌纤维溶解、断裂,间质增大,心肌细胞肿胀明显,SOD活性及ATP含量明显下降,ROS及MDA含量明显上升(均P<0.05),电针预处理可明显减轻这种变化,差异具有统计学意义(均P<0.05),SB230580抑制剂可减弱电针"内关"预处理的这种作用(均P<0.05)。结论电针"内关"预处理能显著改善心肌缺血再灌注损伤后心功能及心肌细胞活性,降低心肌梗死面积,减轻线粒体的肿胀程度,保护线粒体的完整性。这种保护作用可能与改善心肌细胞的呼吸功能有关。

延髓头端腹外侧区在电针预处理减轻心肌缺血再灌注损伤中的作用

ObjectiveTo observe the effects of pretreatment with electroacupuncture (EA) on neuron activity in the rostral ventrolateral medulla (RVLM) of rats with myocardial ischemia-reperfusion injury (MIRI) and explore the central regulatory mechanism of EA in attenuating MIRI.MethodsOf 72 SD rats, 12 were randomly allocated into the group of EA pretreatment + RVLM nucleus damage (EA + RVLM lesion group). The other 60 rats were randomized (20 rats each) into a sham-operation group, a model group, and an EA pretreatment group (EA group). Except for the rats in the sham-operation group, the models of MIRI were prepared by ligating the left anterior descending coronary artery in the model, EA, and EA + RVLM lesion groups. The rats of the EA group were intervened with EA at “Shénmén (神门HT7)” and “Tōnglĭ (通里HT5)”, 1 mA in current intensity and 2 Hz in frequency, for 20 min each time per day. Before modeling, the intervention was given for seven consecutive days. In the EA + RVLM lesion group, 3 weeks after microinjection with the neuronal apoptotic virus at bilateral RVLM, the same EA intervention as the EA group was provided. Afterward, the MIRI models were prepared. In the model group, no EA intervention was given. Using Powerlab electrophysiolograph, ST segment displacement value and arrhythmia score were recorded and analyzed before modeling, 30 min after ligation, and 120 min after reperfusion in each group. The concentration of cardiac troponin (cTnl) was detected with an ELISA assay kit. Using immunofluorescence staining, the expression level of c-fos protein of RVLM was detected in the sham-operation, model, and EA groups separately. Plexon multichannel acquisition processor was adopted to record the neuronal firing and field potential of RVLM in the sham-operation, model, and EA groups.ResultsST segment displacement value, arrhythmia score, and cTnl concentration 30 min after ligation and 120 min after reperfusion were all elevated in the model group compared to the sham-operation group (all P < 0.01). ST segment displacement value, arrhythmia score, and cTnl concentration were lower in the EA group compared to the model and EA + RVLM lesion groups (P < 0.01). Compared with the sham-operation group, the expression level of c-fos and the total firing frequency in RVLM were significantly higher in the model group (P < 0.01). However, the expression level of c-fos and the total firing frequency in RVLM were lower in the EA group compared with the model group (P < 0.01).ConclusionElectroacupuncture pretreatment may induce changes in c-fos protein expression and neuronal activity in RVLM to mitigate myocardial lesions. RVLM plays an important role in electroacupuncture pretreatment for alleviating MIRI.

电针“内关”预处理对心肌缺血再灌注损伤大鼠心肌Akt/mTOR通路的影响

目的观察电针预处理对心肌缺血再灌注损伤(MIRI)模型大鼠心肌组织自噬相关通路Akt/mTOR的影响,探讨电针“内关”对心肌损伤的作用机制。方法将48只SD大鼠按随机数字表法分为空白组、假手术组、模型组和内关组,每组12只。内关组电针刺激大鼠“内关”,每次30 min,1次/d,连续干预7 d。干预结束后,除空白组外,其余各组大鼠采用冠状动脉左前降支结扎法建立MIRI模型。采用HE染色法观察大鼠心肌组织病理形态学改变;Western blot法检测心肌组织Akt、磷酸化Akt(p-Akt)、mTOR、磷酸化mTOR(p-mTOR)蛋白表达,计算p-Akt/Akt、p-mTOR/mTOR比值。结果空白组心肌纤维排列规则整齐,心肌间质未见炎性细胞浸润、出血;假手术组心肌纤维排列稍不规则,未见断裂,可见少量心肌纤维间隙稍扩大;模型组心肌纤维分布紊乱,肥大心肌细胞增多,部分线粒体红肿或外膜破裂,间质可见炎性浸润、出血;内关组心肌组织病变程度较模型组减轻,少量间质出血及炎性细胞浸润。各组大鼠心肌组织Akt、mTOR蛋白表达比较差异无统计学意义(P>0.05);与假手术组比较,模型组p-Akt、p-mTOR表达及p-Akt/Akt、p-mTOR/mTOR降低(P<0.01);与模型组比较,内关组p-Akt、p-mTOR表达及p-Akt/Akt、p-mTOR/mTOR升高(P<0.01)。结论电针“内关”预处理可能通过激活MIRI大鼠心肌细胞Akt/mTOR通路抑制过度自噬,从而减轻MIRI,起到保护心肌的作用。

电针、艾灸预处理对心肌缺血大鼠心肌细胞凋亡和自噬的影响

目的:观察针灸预处理对心肌缺血大鼠心肌细胞凋亡指数和自噬相关蛋白LC3表达的影响,探讨针灸预处理对心肌缺血大鼠心肌细胞自噬能力的预保护作用。方法:SD大鼠随机分为假手术组、模型组、缺血预适应(IP)组、电针组、艾灸组,每组8只。电针组及艾灸组造模前分别电针或艾灸"内关"穴,每天1次,每次20min,连续7d。采用冠状动脉结扎术复制心肌缺血模型。电镜观察左心室缺血区组织病理形态学及心肌细胞自噬体的变化,TUNEL法检测心肌细胞凋亡情况及凋亡指数,Western blot法检测LC3蛋白在心肌组织中的表达情况。结果:假手术组心肌细胞形态完整,排列整齐,线粒体较完整,可见少量自噬空泡;与假手术组相比,模型组心肌细胞形态不完整,排列紊乱,肌纤维溶解,线粒体肿大,胞核边聚化,自噬空泡较多;与模型组相比,IP组、电针组、艾灸组心肌细胞损伤较轻,少量肌纤维溶解,线粒体丰富,自噬空泡及溶酶体数量增多。与假手术组比较,模型组凋亡指数升高(P<0.05);与模型组相比,IP组、电针组、艾灸组凋亡指数均降低(P<0.05);与IP组、艾灸组比较,电针组凋亡指数降低(P<0.05)。与假手术组比较,模型组心肌组织LC3-Ⅱ表达水平、LC3-Ⅱ/Ⅰ比值均升高(P<0.05);与模型组比较,IP组、电针组及艾灸组心肌组织LC3-Ⅱ表达水平及LC3-Ⅱ/Ⅰ比值均降低(P<0.05);与IP组、艾灸组比较,电针组LC3-Ⅱ的表达及LC3-Ⅱ/Ⅰ比值上调(P<0.05)。结论:针灸预处理能产生与缺血预适应相似的心脏保护作用,适度提高细胞自噬能力,减少细胞凋亡。

电针“内关”预处理对心肌缺血再灌注损伤大鼠血清代谢物的影响

目的:基于核磁共振氢谱技术(1 H NMR)观察电针"内关"穴预处理对心肌缺血再灌注损伤(MIRI)大鼠血清代谢物及其代谢通路的影响,从代谢组学角度探讨电针预处理对MIRI大鼠产生保护作用的机制。方法:雄性SD大鼠48只随机分为正常组、模型组、电针内关组(内关组)、电针合谷组(合谷组),每组12只。采用结扎冠状动脉左前降支40min后恢复血流1h制备MIRI大鼠模型。两电针组造模前每天予电针相应穴位30min,连续7d。模型制备成功后,收集各组大鼠血清,利用~1 H NMR进行代谢物检测,利用最小二乘分析、正交偏最小二乘分析进行模式识别。结果:在造模后,模型组、电针组大鼠心电图均表现出T波高耸,R波与T波间无明显ST段。再灌注后T波下降超过0.2mV,无明显ST段。与正常组比较,模型组大鼠血清代谢模式发生明显改变,乙酰乙酸、乳酸、肌酸、丙三醇、葡萄糖升高,丙氨酸、谷氨酰胺、甘油磷酸胆碱、磷酸胆碱降低。与模型组比较,内关组大鼠血清代谢模式发生明显改变,表现为葡萄糖上升,亮氨酸、异亮氨酸、缬氨酸、三羟基丁酸、乳酸、醋酸盐、丙酮、乙酰乙酸、丙酮酸、谷氨酰胺、肌酸、丙三醇下降;合谷组与模型组代谢模式无显著差异。结论:电针"内关"预处理明显改变了MIRI大鼠糖代谢、丙酮酸代谢、氨基酸代谢、酮体代谢、能量代谢的模式,电针"内关"可能通过调节丙酮酸、氨基酸、酮体、能量等对MIRI大鼠起到一定的预保护作用。

电针预处理对急性心肌缺血再灌注损伤大鼠心肌组织水通道蛋白1表达及蛋白激酶C活性的影响

目的:探讨电针"内关"与"太渊"穴预处理对急性心肌缺血再灌注损伤大鼠心肌的保护效应差异及部分作用机制。方法:96只Wistar大鼠随机分为假手术组、模型组、内关组、太渊组,每组24只。内关组与太渊组大鼠分别选取"内关"与"太渊"穴进行电针预处理,刺激电流1mA,频率2Hz,每次20min,每日1次,共干预7d。假手术组、模型组固定相同时间,不予电针干预。模型组、内关组、太渊组大鼠在末次电针24h后进行心肌缺血再灌注模型复制,假手术组在开胸后仅在相应部位用针空穿1次,不进行结扎。分别检测各组大鼠心肌缺血面积、梗死面积,心肌组织蛋白激酶C(protein kinase C,PKC)活性及水通道蛋白1(aquaporin 1,AQP1)表达情况。结果:模型组大鼠的心肌缺血面积、梗死面积、AQP1蛋白表达及PKC的活性显著升高,与假手术组比较差异均有统计学意义(均P<0.01),内关组大鼠的心肌缺血面积、梗死面积、PKC的活性和AQP1蛋白表达较模型组和太渊组均显著减少(P<0.01,P<0.05)。经Pearson相关分析,电针预处理后急性心肌缺血再灌注损伤大鼠心肌组织AQP1蛋白表达和PKC活性的变化呈显著正相关。结论:电针"内关"穴预处理可显著降低急性心肌缺血再灌注损伤大鼠心肌组织AQP1蛋白表达和PKC活性,其作用机制可能是通过抑制PKC活化进而抑制AQP1蛋白表达,从而发挥其心肌保护效应。

电针预处理对心肌缺血再灌注损伤大鼠下丘脑外侧区和小脑顶核多巴胺、5-羟色胺含量的影响

目的:观察电针心经腧穴预处理对急性心肌缺血再灌注损伤(MIRI)大鼠下丘脑外侧区(LHA)与小脑顶核(FN)多巴胺(DA)、5-羟色胺(5-HT)含量的影响,探讨LHA和FN在电针心经腧穴抗急性MIRI效应中的作用及机制。方法:将60只SD大鼠随机分为假手术组、模型组、电针心经组、电针肺经组,每组12只;LHA+心经组(损毁双侧LHA)、FN+心经组(损毁双侧FN),每组6只。核团损毁3 d后,电针心经组、LHA+心经组、FN+心经组电针"神门""通里",电针肺经组电针"太渊""列缺",刺激电压为1 V,频率为2 Hz,每次20 min,每日1次,模型复制前共刺激7 d。除外假手术组,其他各组均采用冠状动脉左前降支结扎法复制MIRI大鼠模型。应用Power lab多导生理记录仪记录造模前、结扎后30 min及再灌注120 min的ST段位移值,采用高效液相色谱-电化学检测分析系统测定各组大鼠造模后LHA、FN透析液中DA、5-HT含量。结果:结扎后30 min、再灌注120 min时各组ST段位移值比较,模型组高于假手术组(P<0.01),电针心经组、LHA+心经组、FN+心经组和电针肺经组低于模型组(P<0.01),电针心经组低于电针肺经组、LHA+心经组和FN+心经组(P<0.01)。模型组大鼠FN、LHA中DA、5-HT含量低于假手术组(P<0.01);除外损毁对应的核团组,各干预组FN、LHA中DA、5-HT含量均高于模型组(P<0.01);电针心经组大鼠FN中DA、5-HT含量高于电针肺经组、LHA+心经组(P<0.01),LHA中5-HT含量高于电针肺经组和FN+心经组、DA含量高于电针肺经组(P<0.01)。结论:电针心经腧穴预处理可以有效减轻急性MIRI大鼠的心肌损伤,LHA、FN中DA、5-HT可能是其重要的物质基础。

电针预处理对心肌缺血再灌注损伤大鼠心肌Gasdermin D、半胱氨酸蛋白酶-1及白细胞介素-1β表达的影响

目的:观察电针预处理对心肌缺血再灌注损伤(MIRI)大鼠心肌细胞焦亡相关蛋白半胱氨酸蛋白酶-1(Caspase-1)、Gasdermin D(GSDMD)、白细胞介素-1β(IL-1β)的影响,探讨电针预处理减轻MIRI损伤的可能机制。方法:SD大鼠随机分为空白组、假手术组、模型组、电针组,每组10只。电针组电针大鼠双侧“内关”,每次20 min,每日1次,连续3 d。采用冠状动脉左前降支结扎法复制MIRI大鼠模型。采用超声心动图观察造模4 h后大鼠左心室射血分数(LVEF)以评估心功能;TTC染色法观察大鼠心肌梗死面积;免疫组织化学法观察大鼠心肌组织中GSDMD表达情况;Western blot法检测心肌组织GSDMD、Caspase-1、IL-1β蛋白表达水平。结果:与空白组相比,假手术组心肌组织GSDMD表达升高(P<0.05)。与假手术组相比,模型组大鼠术后4 h时LVEF明显下降(P<0.0001),梗死面积增大(P<0.0001),心肌组织GSDMD表达显著升高(P<0.0001),心肌GSDMD、Caspase-1、IL-1β蛋白表达升高(P<0.001,P<0.0001)。与模型组相比,电针组大鼠术后4 h时LVEF升高(P<0.001),梗死面积缩小(P<0.0001),心肌组织GSDMD表达降低(P<0.001),心肌GSDMD、Caspase-1、IL-1β蛋白表达降低(P<0.01,P<0.001)。结论:电针预处理可能通过下调Caspase-1蛋白的表达,降低心肌细胞焦亡水平,从而改善MIRI损伤。

电针预处理对心肌缺血/再灌注损伤大鼠线粒体活性氧介导的细胞凋亡的影响

目的:探讨电针预处理对心肌缺血再灌注损伤(MIRI)大鼠的保护作用及其对线粒体活性氧(ROS)的作用机制。方法:将80只SPF级雄性Wistar大鼠随机分为正常组、假手术组、再灌注组和电针组,每组20只。正常组、假手术组、再灌注组均给予捆绑,电针组给予电针预处理,均20 min/次,1次/d,共7 d。第8天正常组麻醉50 min后、假手术组开胸暴露心脏50 min后、再灌注组及电针组开胸缺血20 min再灌注30 min后取材。根据心电图STⅡ段变化,判断MIRI模型是否成功;采用室性心律失常(VA)评分评价心律失常情况;采用ELISA法检测血清肌酸激酶同工酶(CK-MB)含量;采用DHE染色法检测心肌组织中ROS含量;采用实时荧光定量PCR法检测心肌组织中细胞色素C(Cyt-C)、半胱天冬酶9(Caspase-9)、半胱天冬酶3(Caspase-3)基因表达水平。结果:正常组与假手术组在各项指标上差异均无统计学意义(P>0.05);与假手术组比较,再灌注组的VA评分、血清CK-MB含量、心肌ROS含量及Cyt-C、Caspase-9、Caspase-3 mRNA表达均明显升高(P<0.01);与再灌注组比较,电针组VA评分、血清CK-MB含量、心肌ROS含量及Cyt-C、Caspase-9、Caspase-3 mRNA表达均明显下降(P<0.01)。结论:电针预处理对MIRI大鼠的保护作用可能是基于调控ROS介导的凋亡通路产生的。

电针预处理对心肌缺血再灌注大鼠的保护作用及FXR/SHP基因的调控作用

目的:探讨电针预处理对大鼠心肌缺血再灌注损伤的保护机制。方法:将SPF级雄性Wistar大鼠88只,随机分为正常组、假手术组、模型组和电针组,每组22只。正常组常规饲养7 d,不做任何处理;假手术组和模型组每日捆绑1次,每次20 min,共7 d;电针组电针"内关""足三里""关元"穴,每天1次,频率2 Hz、强度为1 mA的连续波,每次20 min,共7 d。第8天,正常组采用10%乌拉坦(10 mL/kg)腹腔注射麻醉后60 min腹主动脉取血,再取心脏组织;模型组与电针组结扎左冠状动脉前降支20 min,再灌注40 min后取样;假手术组开胸后不做任何处理,60min后取样。采用氯化硝基四氮唑蓝(NBT)染色法测定缺血再灌注损伤后大鼠心肌梗死的面积和梗死区质量,采用酶联免疫分析法检测心肌损伤标志物和炎性因子[血清乳酸脱氢酶(LDH)、肌酸激酶(CK)、血清肌钙蛋白(c Tn I)]含量,采用荧光定量PCR法检测法尼酯衍生物X受体(FXR)、小异二聚体配体(SHP)基因表达情况。结果:①与正常组比较,假手术组心肌梗死面积与梗死区质量比较差异无统计学意义(均P>0.05),模型组的梗死面积与梗死区质量均升高(均P<0.01),电针组的梗死面积与梗死区质量均低于模型组(均P<0.01)。②与正常组比较,假手术组血清LDH、CK、c Tn I各项指标比较差异无统计学意义(均P>0.05);与正常组比较,模型组血清LDH、CK和c TnI水平均升高(均P<0.05),电针组血清LDH、CK和c TnI水平均低于模型组(均P<0.05)。③模型组FXR、SHP基因表达水平明显高于正常组(P<0.05),电针组FXR、SHP基因表达水平低于模型组(均P<0.05)。结论:电针预处理能显著改善大鼠心肌缺血再灌注后的心功能,降低梗死面积,减少炎性因子,下调FXR/SHP的基因表达,其保护作用可能是基于调控FXR/SHP凋亡信号通路产生的。

电针内关穴预处理对大鼠心肌缺血再灌注后线粒体功能及超微结构的保护作用

目的:探讨电针内关穴预处理对心肌缺血再灌注损伤过程中心肌线粒体的保护作用。方法:选用3月龄Wistar雄性大鼠30只,体质量(220±28)g,编号后按随机数字表分入空白组、模型组、电针预处理组,每组10只。造模采用结扎左冠状动脉前降支,缺血30min,再灌注2h,随即处死大鼠,留取左心室心肌组织,采用黄嘌呤氧化法检测心肌超氧化物歧化酶(SOD)活性,硫代巴比妥酸法检测心肌丙二醛(MDA),通过极谱法检测系统测定线粒体呼吸控制率(RCR),透射电镜下观察心肌超微组织的变化。结果:电针预处理组大鼠部分心肌肌丝溶解、断裂,心肌细胞轻微肿胀,轻度空化,线粒体排列稍紊乱,部分线粒体水肿、存在空泡样病变。电针预处理组的大鼠线粒体RCR、SOD及ATP含量明显高于模型组(P<0.01),MDA含量明显低于模型组(P<0.01)。结论:电针内关穴预处理能改善心肌组织形态学表达,防止心肌组织结构的破坏,修护心肌缺血性损伤,更对线粒体的结构与功能起到了良性的保护作用。