Paracrine regulation of cardiac myocytes in normal and septic heart

A paracrine pathway for the regulation of cardiac contractile function by nonmuscle cells is documented in the heart. Coronary and endocardial endothelium release several diffusible agents, such as prostaglandins, endothelin-1, and nitric oxide, with an action on cardiac myocyte function. Cardiac diseases involving an immune or inflammatory mechanism, such as endotoxic shock, are now seen as conditions in which cross-talk between different cell types in the heart is clearly implicated. The potential biological relevance of inducible nitric oxide synthase in the myocardium, and the subsequent production of nitric oxide has been proposed as a mechanism of the cardiac depression observed in septic shock. In addition to cardiac myocytes, activated microvascular endothelial cells and cardiac endothelial cells may contribute to nitric oxide generation and, ultimately, to the depression of myocardial contractile activity during sepsis. This article reviews the local intercellular communication between cardiac myocytes and endothelial cells in the normal heart and discusses some of the mechanisms potentially claimed to depress heart function in sepsis.     

Enhancement of repopulation haemopoiesis by heterozygous connexin 43 stem cells seeded on wild-type connexin 43 stroma

The present paper analyses the results of competitive blood-cell repopulation experiments in which Cx43-WT (connexin 43 wild-type) host mice, whose own HSCs (haemopoietic stem cells) were deleted, were grafted with fetal liver cells: 50% Gpi-1a (glucose phosphate isomerase-1a)/Cx43-WT cells competing with 50% Gpi-1b/Cx43-WT, 50% Gpi-1b/Cx43-HZ (heterozygous) or 50% Gpi-1b/Cx43-KO (knock-out) cells. The percentages of platelets, granulocytes, red cells, B-cells and T-cells containing Gpi-1b in blood samples obtained from 22 to 186 days after grafting, and the percentages of high-proliferation-potential colony-forming cells containing Gpi-1b at 255 days after grafting, were measured. The results show that, if we wait 4 months so that we measure the percentages of Gpi-1b end-cells formed by initially resting stem cells in the graft, values in HZ mice are greater than those in WT and KO mice by 10% or more. We propose a bipolar influence model for blood formation by grafted HSCs to explain this difference and other features of the data. Influence A is a direct one: for individual HSCs, the combined effect on HSC niching and HSC proliferation of Cx43 is superior to that of the KO allele. Influence B is a demographic one: HZ foundation mice compensate by having more HSCs than WT mice. The net outcome of influences A and B is that HZ is the winner.     

缝隙连接蛋白Cx32与Cx43在癫痫发病中的作用

目的:探讨缝隙连接蛋白(Cx)与癫痫之间的关系.方法:采用免疫组织化学方法测定氯化锂-匹罗卡品致痫大鼠癫痫发作后不同时间不同脑区Cx32与Cx43免疫阳性表达情况.结果:与对照组比较,致痫组大鼠海马区与皮层区Cx32和Cx43免疫阳性表达在癫痫发作1h后开始增强(Cx32免疫阳性细胞数分别为海马区16.62±4.51和皮层区14.85±3.30,均P＜0.05;Cx43免疫阳性细胞数分别为海马区18.26±4.03和皮层区18.65±4.51,均P＜0.01),24 h达到高峰(Cx32免疫阳性细胞数分别为海马区46.53±9.47和皮层区28.25±8.69,均P＜0.01;Cx43免疫阳性细胞数分别为海马区39.77±7.79和皮层区26.50±6.56,均P＜0.01),此后逐步下降.但至14 d Cx32海马区与皮层区免疫阳性细胞数分别为22.45±6.56和15.92±3.16,仍高于对照组(均P＜0.05),而Cx43在14 d的表达则有所不同:海马区免疫阳性细胞数17.54±3.77仍高于对照组(P＜0.01);皮层区表达则降至正常水平.致痫24 h时海马区Cx32和Cx43免疫阳性表达均明显高于同一时限的皮层区(均P＜0.05).结论:Cx32和Cx43参与了癫痫的发生与发展过程,反映了脑组织中神经元、星形胶质细胞之间的缝隙连接与癫痫发病机制密切相关.     

心室纤颤时心肌缝隙连接蛋白Cx43的变化

目的 观察心室纤颤(室颤)发生后缝隙连接蛋白Cx43的表达以及缝隙连接改造剂ZP123对Cx43表达的影响.方法 按照随机数字表法将30只家猪分为假手术组、模型组和ZP123干预组,每组10只.以80 V电压持续刺激动物5 s诱发室颤;致颤前15 min ZP123组给予ZP123 1μg/kg静脉推注+ZP12310μg·kg-1·h-1微量泵泵入;模型组泵入生理盐水50 ml;假手术组动物不致颤也不补液.室颤持续8 min后开胸取左心室游离壁心肌,用免疫荧光结合激光共聚焦显微镜技术检测Cx43的分布及水平,用蛋白质免疫印迹法(Western blotting)定量检测Cx43蛋白表达.结果 假手术组Cx43荧光信号强,分布均匀;模型组Cx43荧光信号弱,呈不均一分布;ZP123干预组Cx43荧光信号增强,不均一分布减轻.与假手术组比较,模型组心室肌组织Cx43荧光信号面积百分比、积分吸光度(A)值及蛋白表达均明显下降[面积百分比:(0.64±0.36)%比(1.27±0.19)%,积分A值:15 201±2 613比30 634±4 975,Cx43蛋白表达:0.72±0.08比0.97±0.07,均P＜0.05];与模型组比较,ZP123干预组Cx43表达[面积百分比(0.96±0.16)%,积分A值22 100±4 404,Cx43蛋白表达0.82±0.04]均明显升高(均P＜0.05).结论 室颤发生时心肌组织Cx43表达减少;应用ZP123可减少或逆转Cx43的降解.     

Gene transfer of connexin43 into skeletal muscle

Cellular cardiomyoplasty using skeletal myoblasts may be beneficial for infarct repair. One drawback to skeletal muscle cells is their lack of gap junction expression after differentiation, thus preventing electrical coupling to host cardiomyocytes. We sought to overexpress the gap junction protein connexin43 (Cx43) in differentiated skeletal myotubes, using retroviral, adenoviral, and plasmid-mediated gene transfer. All strategies resulted in overexpression of Cx43 in cultured myotubes, but expression of Cx43 from constitutive viral promoters caused significant death upon differentiation. Dye transfer studies showed that surviving myotubes contained functional gap junctions, however. Retrovirally transfected myoblasts did not express Cx43 after grafting into the heart, possibly due to promoter silencing. Adenovirally transfected myoblasts expressed abundant Cx43 after forming myotubes in cardiac grafts, but grafts showed signs of injury at 1 week and had died by 2 weeks. Interestingly, transfection of already differentiated myotubes with adenoviral Cx43 was nontoxic, implying a window of vulnerability during differentiation. To test this hypothesis, Cx43 was expressed from the muscle creatine kinase (MCK) promoter, which is active only after myocyte differentiation. The MCK promoter resulted in high levels of Cx43 expression in differentiated myotubes but did not cause cell death during differentiation. MCK-Cx43-transfected myoblasts formed viable cardiac grafts and, in some cases, Cx43-expressing myotubes were in close apposition to host cardiomyocytes, possibly allowing electrical coupling. Thus, high levels of Cx43 during skeletal muscle differentiation cause cell death. When, however, expression of Cx43 is delayed until after differentiation, using the MCK promoter, myotubes are viable and express gap junction proteins after grafting in the heart. This strategy may permit electrical coupling of skeletal and cardiac muscle for cardiac repair.     

急性心房颤动犬缝隙连接蛋白40和43重构及胺碘酮的干预作用

目的 采用快速心房起搏致犬急性心房颤动(简称房颤)模型,观察心房肌缝隙连接蛋白40和43(Cx40、Cx43)含量的改变以及胺碘酮干预的效果.方法 18只成年杂种犬,随机等分为三组,即正常对照组、急性房颤组、胺碘酮组.快速心房起搏,对照组不起搏,胺碘酮组先静脉注射胺碘酮负荷量3 mg/kg,10～15 min内注入,后以维持量1.5 mg/kg静脉滴注进行干预,另两组给予等容量的生理盐水.连续刺激并且房颤8 h后,取右心耳组织,用Western blot 检测Cx40和Cx43的含量,用Lucifer Yellow划痕标记荧光传输技术在荧光显微镜上观察细胞缝隙连接通讯状态.结果 急性房颤组心房肌组织Cx40和Cx43含量较对照组降低(P均<0.05),胺碘酮组Cx40、Cx43含量较正常对照组低,差异有显著性(P均<0.05),较房颤组含量差异无显著性(P>0.05),胺碘酮可以改善急性房颤时细胞缝隙连接通讯的传导.结论 急性房颤犬缝隙连接蛋白40和43发生了结构重构,从而影响细胞间通讯,胺碘酮可以改善细胞间电信号传导,但不能改善缝隙连接结构重构.     

卡维地洛对连接蛋白43的分布及数量的影响

目的观察卡维地洛对心肌梗死边缘区Cx43分布的影响。方法36只家兔随机分为梗死组,卡维地洛组,假手术组,每组12只。梗死组和卡维地洛组开胸结扎冠状动脉左前降支,假手术组不结扎。所有家兔普通饲料喂养,卡维地洛组另给予卡维地洛5mg·kg^-1·d^-1。12周后观察：（1）共聚焦激光显微镜观察梗死边缘区Cx43的分布,（2）Werstem Blot检查梗死边缘区Cx43的蛋白表达。结果（1）共聚焦激光显微镜下观察心肌梗死组Cx43荧光斑的形态相对粗乱,呈现不均一分布;卡维地洛组Cx43的荧光分布改变较少,不均一分布的程度较心肌梗死组减轻;心梗组的Cx43相对密度显著低于卡维地洛组;[（0．16±0．06）％vs（0．32±0．11）％,P〈0．05];（2）Werstem Blot检查梗死组Cx43及卡维地洛组较假手术组减少,但卡维地洛组的Cx43表达较心肌梗死组增多[（0．89±0．28）vs（0．67±0．32）,P〈0．05]。结论卡维地洛可以引起Cx43的再分布,增加心肌梗死后Cx43蛋白的表达,这可能是其较减少心肌梗死后室性心律失常的原因之一。     

室性心动过速时连接蛋白43含量与分布的变化

目的　探讨室性心动过速 (室速 )时心肌细胞连接蛋白 4 3(Cx 4 3)含量和分布的变化。方法　实验用日本大耳白兔 2 0只 ,随机分为对照组、30min室速组、6 0min室速组、12 0min室速组 4组。分别通过心室刺激复制室性心动过速动物模型 ,应用激光共聚焦显微镜技术和荧光免疫组织化学方法对其发生心律失常心肌连接蛋白 4 3的含量和分布进行定量分析。结果　 30min室速组连接蛋白 4 3像素密度较对照组减少 18.4 % (P <0 .0 5 ) ,6 0min室速组减少 38.0 % (P <0 .0 1) ,12 0min室速组减少 5 4 .8% (P <0 .0 1)。对照组各层间心肌细胞连接蛋白 4 3含量比较无显著差异 ,但心律失常后 ,中间层心肌细胞连接蛋白 4 3含量较其他层心肌细胞含量下降更明显 (P <0 .0 5或P <0 .0 1)。结论　室性心动过速时连接蛋白 4 3迅速降解 ,其分布也发生明显的改变 ,各层心肌细胞连接蛋白 4 3的降解程度也明显不均一。     

Antibody-mediated enhancement of calcium permeability in cardiac myocytes

Our study shows that antibodies, specific to the ADP/ATP carrier of the inner mitochondrial membrane, crossreact with the cell surface of cardiac myocytes, where the calcium channel seems to be the antigenic determinant. The antibodies enhanced the calcium current and suppressed its inactivation. Affinity-purified antibodies (IgG) exhibit an acute cytotoxic effect, which required extracellular calcium and was prevented by calcium channel blockers. Our findings suggest that antibody-mediated cytotoxicity results secondary to calcium overload caused by enhanced cellular calcium permeability, requiring no complement-dependent process.     

食管鳞癌间隙连接蛋白Cx32和Cx43的检测及意义

摘要：目的：检测间隙连接蛋白（connexin,Cx）32和43在食管鳞癌的表达,探讨其在食管鳞癌发生、发展中的作用及临床意义。 方法：用免疫组织化学技术（Elivision法）检测78例食管鳞癌组织和22例癌旁食管鳞状上皮组织中Cx32和Cx43的表达情况。 结果：癌旁食管鳞状上皮中Cx32和Cx43主要表达于细胞膜,阳性表达率均显著高于癌组织。Cx32和Cx43在食管鳞癌细胞膜表达与组织的分化程度、浸润深度、淋巴结转移及临床分期均有一定相关性,而与性别、年龄和病变部位无关。 结论：Cx32和Cx43的表达随着食管鳞癌病理分级的增高而降低,其异常表达可能是食管鳞癌发生、发展的重要因素之一。     

The heme oxygenase inducer hemin protects against cardiac dysfunction and ventricular fibrillation in ischaemic/reperfused rat hearts: role of connexin 43

Cardiac expression of cytoprotective gene heme oxygenase‐1 (HO‐1) is modulated by ischaemia and reperfusion (I/R). We therefore hypothesized that pretreatment with hemin, an inductor of HO‐1, would precondition the heart against post‐ischaemic dysfunction and ventricular fibrillation (VF). Male Wistar rats were given either hemin or HO enzyme inhibitor zinc protoporphyrin IX (ZnPP IX). Isolated hearts were subjected to 30?min global ischaemia followed by 120?min of reperfusion or were aerobically perfused in a time‐matched non‐ischaemic protocol. Control animals received no pretreatment. Compared to non‐perfused controls, pretreatment with hemin increased HO‐1 mRNA 13‐fold (p<0.001) and HO‐1 protein 3.5‐fold (p?0.001), improved post‐ischaemic aortic flow, coronary flow, LVDP and ?Dp/dt (p<0.01) and decreased LVEDP (p<0.001) and the incidence of VF (p = 0.001). The improved post‐ischaemic cardiac function and reduction of VF were accompanied by a higher total connexin 43 (Cx43) level compared to non‐pretreated and ZnPP IX pretreated hearts, and accumulation of non‐phosphorylated gap junction protein Cx43 in intercalated discs and lateral plasma membrane of cardiomyocytes. Cardioprotection by HO‐1 appeared to be independent of cGMP. Administration of ZnPP IX had no effect on cardiac function or VF. Our results show that pharmacological modulation of HO‐1 pathway may provide a new therapeutic approach to protect the heart against post‐ischaemic dysfunction and I/R‐induced VF possibly by a Cx43 dependent mechanism.     

The heme oxygenase inducer hemin protects against cardiac dysfunction and ventricular fibrillation in ischaemic/reperfused rat hearts: role of connexin 43

Cardiac expression of cytoprotective gene heme oxygenase-1 (HO-1) is modulated by ischaemia and reperfusion (I/R). We therefore hypothesized that pretreatment with hemin, an inductor of HO-1, would precondition the heart against post-ischaemic dysfunction and ventricular fibrillation (VF). Male Wistar rats were given either hemin or HO enzyme inhibitor zinc protoporphyrin IX (ZnPP IX). Isolated hearts were subjected to 30 min global ischaemia followed by 120 min of reperfusion or were aerobically perfused in a time-matched non-ischaemic protocol. Control animals received no pretreatment. Compared to non-perfused controls, pretreatment with hemin increased HO-1 mRNA 13-fold (p<0.001) and HO-1 protein 3.5-fold (p相似文献   

组织工程化成年心肌细胞的构建

背景：采用成年心肌细胞构建组织工程细胞已成为心脏疾病领域新的科研热点。 目的：探讨简单、快捷的成年大鼠心肌细胞分离方法,并初步探索组织工程化成年心肌细胞的构建方式。 方法：采用分段式酶消化方法消化成年大鼠心室肌心肌细胞。分别转染腺病毒和脂质体介导的红色荧光蛋白基因,倒置荧光显微镜、流式细胞仪检测组织工程细胞的构建效率。转染腺病毒介导的缺氧诱导因子1a,采用Western blot检测目标蛋白的表达。 结果与结论：采用分段式酶消化方法可获得大量心肌细胞。流式细胞分析表明所获得的成年心肌细胞的存活率为（87.03±0.70）%。与脂质体转染相比（转染效率为0）,腺病毒感染效率高,为（70.31±1.39）%,荧光显微镜下细胞发出红色荧光。在腺病毒转染第4天后,可有效表达目标蛋白缺氧诱导因子1a。以上结果表明分段式酶消化法是成熟心肌细胞的快速分离方式,并明确重组腺病毒载体是转染心肌细胞的最佳基因载体。     

甘珀酸对癫痫大鼠脑组织缝隙连接蛋白43表达的干预及其意义

目的 探讨癫痫大鼠脑组织缝隙连接蛋白43(connexin43,Cx43)表达及缝隙连接阻断剂甘珀酸(carbenoxolone,CBX)对其表达的影响.方法 健康SD大鼠64只,随机分为正常对照组、致痫组、致痫+生理盐水组(致痫+NS组)和致痫+CBX干预组(致痫+CBX组).采用免疫组化染色方法和实时荧光定量逆转录-聚合酶链反应方法分别测定氯化锂-匹罗卡品癫痫模型大鼠脑组织Cx43免疫阳性细胞数及Cx43mRNA表达水平,并观察腹腔注射CBX对Cx43表达的影响.结果 与正常对照组比较,致痫大鼠脑组织Cx43免疫阳性细胞数及其mRNA表达差异倍数在致痫1 h开始明显增多,并持续至7 d(P＜0.05).大鼠注射CBX后Cx43免疫阳性细胞数及其mRNA表达差异倍数均明显低于同一时间点致痫组和致痫+NS组(P＜0.05),海马区Cx43免疫阳性细胞数及其mRNA表达差异倍数在注射CBX 7 d后降至正常水平,而皮层区Cx43免疫阳性细胞数及其mRNA表达差异倍数在注射CBX 3 d后降至正常水平.结论 星形胶质细胞Cx43参与了癫痫发作和发展过程.CBX减少致痫大鼠脑组织Cx43表达,具有较明确的抗癫痫作用.     

Slow ventricular conduction in mice heterozygous for a connexin43 null mutation.

To characterize the role of the gap junction protein connexin43 (Cx43) in ventricular conduction, we studied hearts of mice with targeted deletion of the Cx43 gene. Mice homozygous for the Cx43 null mutation (Cx43 -/-) die shortly after birth. Attempts to record electrical activity in neonatal Cx43 -/- hearts (n = 5) were unsuccessful. Ventricular epicardial conduction of paced beats, however, was 30% slower in heterozygous (Cx43 -/+) neonatal hearts (0.14+/-0.04 m/s, n = 27) than in wild-type (Cx43 +/+) hearts (0.20+/-0.07 m/s, n = 32; P < 0.001). This phenotype was even more severe in adult mice; ventricular epicardial conduction was 44% slower in 6-9 mo-old Cx43 -/+ hearts (0.18+/-0.03 m/s, n = 5) than in wild-type hearts (0.32+/-0.07 m/s, n = 7, P < 0.001). Electrocardiograms revealed significant prolongation of the QRS complex in adult Cx43 -/+ mice (13.4+/-1.8 ms, n = 13) compared with Cx43 +/+ mice (11.5+/-1.4 ms, n = 12, P < 0.01). Whole-cell recordings of action potential parameters in cultured disaggregated neonatal ventricular myocytes from Cx43 -/+ and +/+ hearts showed no differences. Thus, reduction in the abundance of a major cardiac gap junction protein through targeted deletion of a Cx43 allele directly leads to slowed ventricular conduction.     

Induction of the skeletal alpha-actin gene in alpha 1-adrenoceptor-mediated hypertrophy of rat cardiac myocytes.

Myocardial hypertrophy in vivo is associated with reexpression of contractile protein isogenes characteristic of fetal and neonatal development. The molecular signals for hypertrophy and isogene switching are unknown. We studied alpha (sarcomeric)-actin messenger RNA (mRNA) expression in cultured cardiac myocytes from the neonatal rat. In the cultured cells, as in the adult heart in vivo, expression of cardiac alpha-actin (cACT) predominated over that of skeletal alpha-actin (sACT) mRNA, the fetal/neonatal isoform. alpha 1-Adrenergic receptor stimulation induced hypertrophy of these cells, increasing total RNA and cytoskeletal actin mRNA by 1.8-fold over control, and total alpha-actin mRNA by 4.3 fold. This disproportionate increase in total alpha-actin mRNA was produced by a preferential induction of sACT mRNA, which increased by 10.6-fold over control versus only 2.6-fold for cACT mRNA. The alpha 1-adrenoceptor is the first identified molecular mediator of early developmental isogene reexpression in cardiac myocyte hypertrophy.     

Interleukin-1 beta modulates the growth and phenotype of neonatal rat cardiac myocytes.

Mononuclear cell infiltration and local cytokine elaboration are hallmarks of inflammatory and immunologic heart diseases. To test the hypothesis that cytokines can modulate cardiac myocyte growth and phenotype, myocytes cultured from neonatal rat hearts were exposed to IL-1 beta, an inflammatory cytokine prevalent in myocardial inflammation. IL-1 beta (2 ng/ml, 24 h) increased [3H]leucine incorporation by 30 +/- 4% (P < 0.001, n = 29) and net cellular protein content by 20 +/- 4% (P < 0.001, n = 27), but had no effect on DNA synthesis. Northern hybridization showed that IL-1 beta increased prepro-atrial natriuretic factor (ANF) mRNA (5.8 +/- 1.5-fold, P < 0.01, n = 13) and beta-myosin heavy chain (beta-MHC) mRNA (> 10-fold, n = 4), and decreased mRNA levels for sarcoplasmic reticulum Ca(2+)-ATPase (SERCA2) (-46 +/- 7%; P < 0.001; n = 11), calcium release channel (CRC) (-65 +/- 11%, P < 0.001, n = 8) and voltage-dependent calcium channel (VDCC) (-53 +/- 7%, P < 0.001, n = 8). NG-monomethyl-L-arginine (1 mM), an inhibitor of nitric oxide (NO) synthesis, did not inhibit the IL-1 beta-induced protein synthesis or changes in mRNA levels. In ventricular myocardium obtained from adult rats treated with lipopolysaccharide (4 mg/kg intraperitoneally 18 h) to stimulate systemic cytokine production, there were changes in the mRNA levels for beta-MHC (6 +/- 1-fold, P < 0.01, n = 4), SERCA2 (-65 +/- 4%, P < 0.0001, n = 4), CRC (-67 +/- 5%, P < 0.001, n = 4), and VDCC (-58 +/- 5%, P < 0.001; n = 4) that were qualitatively similar to those observed in cultured myocytes. Thus, IL-1 beta, acting via an NO-independent mechanism, caused myocyte hypertrophy associated with induction of fetal genes (ANF and beta-MHC) and downregulation of three important calcium regulatory genes (SERCA2, CRC, and VDCC). IL-1 beta may contribute to the abnormal structural and functional alterations of cardiac myocytes in conditions marked by mononuclear cell infiltration.     

辛伐他汀对成骨细胞增殖分化及连接蛋白43表达的调控

背景：辛伐他汀对成骨细胞增殖分化的影响以及分子机制尚不完全明了,尤其对连接蛋白43的作用知之甚少。 目的：探讨辛伐他汀对成骨细胞增殖分化及成骨基因和连接蛋白43表达的调控作用。 方法：选取新生SD大鼠,采用颅盖骨消化法培养成骨细胞。采用不同浓度辛伐他汀（0.0625,0.125,0.25,0.5和1.0μmol/L）处理成骨细胞,MTT检测辛伐他汀对成骨细胞增殖作用的影响;碱性磷酸酶活性检测辛伐他汀对成骨细胞分化作用的影响;实时定量RT-PCR和免疫印迹检测细胞成骨基因和间隙连接蛋白43 mRNA和蛋白的表达。 结果与结论：细胞培养第3天,辛伐他汀组各浓度组MTT吸光度值比较差异无显著性意义（P 〉0.05）;但是培养第4天和第5天,辛伐他汀各浓度组MTT吸光度值低于对照组（P 〈0.05）。通过不同浓度辛伐他汀处理成骨细胞后,与对照组比较,成骨细胞碱性磷酸酶活性增加（P〈0.05）,且0.25μmol/L 浓度组作用对成骨细胞碱性磷酸酶活性的影响最为显著。采用0.25μmol/L辛伐他汀处理成骨细胞后,辛伐他汀组与对照组比较,成骨细胞骨钙蛋白、碱性磷酸酶、Ⅰ型胶原和连接蛋白43 mRNA和蛋白表达均增加（P 〈0.05）。提示辛伐他汀可能通过上调成骨基因和间隙连接蛋白43 mRNA 和蛋白的表达来抑制成骨细胞增殖和促进其分化,这为他汀类药物治疗骨质疏松症提供新的干预靶点。     

缝隙连接蛋白Cx43在SD大鼠电点燃癫痫模型中的表达

目的探讨缝隙连接蛋白(Cx)在癫痫形成中的作用。方法将32只雄性SD大鼠随机分为4组,分别造模。观察SD大鼠行为,记录脑电图。通过免疫蛋白印迹的方法检测Cx43在大鼠海马区的表达变化。通过药物对癫痫电点燃模型成模过程的干预来观察癫痫形成与缝隙连接蛋白间的关系。结果模型组大鼠出现癫痫发作。蛋白印迹显示Cx43的表达异常增高。药物干预的2组SD大鼠模型痫性发作滞后,发作频率降低,程度减轻,痫性脑电波波幅降低,蛋白印迹显示Cx43的表达增高受到抑制。结论缝隙连接蛋白是癫痫形成的物质基础。抑制Cx43的过度表达,减少异常缝隙连接的形成,癫痫形成也受到抑制,从而预防癫痫产生。