微小RNA-144表达对大鼠心肌细胞凋亡的影响

目的 探讨微小RNA-144(miR-144)对心肌细胞凋亡的影响.方法运用转染的方法,使大鼠H9C2胚胎心肌细胞中高表达miR-144(miR-144组),实时定量PCR确定miR-144表达上调后,通过细胞计数试剂盒-8(CCK-8)、半胱天冬酶(Caspase)-3、流式细胞术等方法测定细胞凋亡水平,观察miR-144对细胞凋亡的影响.空白脂质体及随机微小RNA片段作为空白对照及阴性对照.结果实时定量PCR结果显示,miR-144组miR-144的表达(2178.84±838.52)明显高于空白对照组(1.00±0.00)和阴性对照组(2.06±0.73)(P均＜0.01).与阴性对照组和空白对照组比较,miR144组细胞增殖明显低、Caspase-3活性明显高、细胞凋亡率明显高,而阴性对照组与空白对照组以上数值比较差异均无统计学意义.结论合成的miR-144片段(miR-144 mimics)能选择性上调miR144的表达,并促进心肌细胞凋亡、抑制细胞增殖.

Abstract：

Objective To investigate the effects of microRNA-144 (miR-144) expression on H9C2(2-1) myocytes. Methods MiR-144 was up-regulated in primary cultured H9C2 (2-1) myocytes through transfection. Cells transfected with LipofectamineTM 2000 and its mixture with miRNA synthesized randomly as blank control and negative control respectively. The up-regulation of miR-144 was confirmed by real-time PCR. Cell apoptosis was evaluated by means of CCK-8, Caspase-3 and flow cytometry. Results Real-time PCR results showed that the miR-144 expression was obviously increased in miR-144 up-regulation group (2178.84±838.52) compared with negative (2.06±0.73) and blank (1.00±0.00) control group ( all P ＜0. 01 ). The proliferation was lower, the activity of Caspase-3 was elevated and the apoptosis rates were significantly increased in miR-144 up-regulation group compared with negative and blank control group,while no significant difference was found between the latter 2 groups. Conclusion MiR-144 mimics may selectively up-regulate the expression of miR-144 in myocardial cells and consequently promote apoptosis and inhibit proliferation in myocardial cells.     

微小RNA-34a调控高糖诱导H9c2心肌细胞凋亡的初步研究

目的探讨微小RNA-34a(miR-34a)对高糖诱导的H9c2心肌细胞凋亡的影响。方法将培养的H9c2心肌细胞随机分为3组:正常组(葡萄糖浓度5.5mmol/L)、高糖组(葡萄糖浓度33mmol/L),抑制剂组(miR-34a抑制剂浓度50nmol/L+葡萄糖33mmol/L)。采用定量PCR检测miR-34a和凋亡相关基因Bcl-2基因表达的变化,Western blot检测凋亡相关蛋白Bcl-2表达的变化;采用流式细胞术检测细胞凋亡。结果与正常组比较,高糖组心肌H9c2细胞凋亡率明显升高(P<0.05),H9c2细胞miR-34a表达显著上调(P<0.05),H9c2细胞Bcl-2mRNA和蛋白表达减少(P<0.05)。与高糖组比较,抑制剂组H9c2细胞凋亡明显下降(P<0.05),H9c2细胞Bcl-2mRNA和蛋白表达明显升高(P<0.05)。结论 miR-34a能调控高糖所致的H9c2心肌细胞凋亡,可能是通过直接抑制抗凋亡基因Bcl-2的表达而实现的。     

胰腺癌Bcl-2,P53蛋白表达和细胞凋亡

目的　探讨ｂｃｌ２ ,ｐ５３ 基因和细胞凋亡在胰腺癌发病机制中的作用以及它们之间相互关系．方法　应用ＡＢＣ 免疫组化技术检测５０ 例胰腺癌中Ｂｃｌ２ 和Ｐ５３ 蛋白表达,运用原位末端标记法观察肿瘤中细胞凋亡数量．结果　Ｐ５３ 蛋白表达阳性率为５４ ％ ,临床Ⅰ期阳性率（２６－７ ％ ）却显著低于Ⅱ期（６１－１ ％ ） 和Ⅲ＋ Ⅳ期（７０－６ ％ ,Ｐ＜ ０－０５） ;Ｂｃｌ２蛋白表达阳性率为６４ ％ ,临床Ⅰ期阳性率（９３－３ ％ ） ,显著高于Ⅱ期（５５－６ ％ ） 和Ⅲ＋ Ⅳ期（４７－１ ％ ,Ｐ＜ ０－０５） ;组织学Ⅲ级癌细胞中凋亡指数明显高于Ⅰ,Ⅱ级（ Ｐ＜ ０－０５） ,Ｂｃｌ２ 蛋白阴性病例中凋亡指数明显高于Ｂｃｌ２ 阳性者（ Ｐ＜ ０－０１） ．结论　Ｂｃｌ２ 是通过抑制细胞凋亡参与肿瘤的生长过程,Ｂｃｌ２和Ｐ５３ 蛋白表达之间 存在密切负相关（τ＝ － ０－１７４７ ,Ｐ＜ ０－０５） ．     

微小RNA-144表达对大鼠心肌细胞凋亡的影响

Objective To investigate the effects of microRNA-144 (miR-144) expression on H9C2(2-1) myocytes. Methods MiR-144 was up-regulated in primary cultured H9C2 (2-1) myocytes through transfection. Cells transfected with LipofectamineTM 2000 and its mixture with miRNA synthesized randomly as blank control and negative control respectively. The up-regulation of miR-144 was confirmed by real-time PCR. Cell apoptosis was evaluated by means of CCK-8, Caspase-3 and flow cytometry. Results Real-time PCR results showed that the miR-144 expression was obviously increased in miR-144 up-regulation group (2178.84±838.52) compared with negative (2.06±0.73) and blank (1.00±0.00) control group ( all P ＜0. 01 ). The proliferation was lower, the activity of Caspase-3 was elevated and the apoptosis rates were significantly increased in miR-144 up-regulation group compared with negative and blank control group,while no significant difference was found between the latter 2 groups. Conclusion MiR-144 mimics may selectively up-regulate the expression of miR-144 in myocardial cells and consequently promote apoptosis and inhibit proliferation in myocardial cells.     

微小RNA-144表达对大鼠心肌细胞凋亡的影响

Objective To investigate the effects of microRNA-144 (miR-144) expression on H9C2(2-1) myocytes. Methods MiR-144 was up-regulated in primary cultured H9C2 (2-1) myocytes through transfection. Cells transfected with LipofectamineTM 2000 and its mixture with miRNA synthesized randomly as blank control and negative control respectively. The up-regulation of miR-144 was confirmed by real-time PCR. Cell apoptosis was evaluated by means of CCK-8, Caspase-3 and flow cytometry. Results Real-time PCR results showed that the miR-144 expression was obviously increased in miR-144 up-regulation group (2178.84±838.52) compared with negative (2.06±0.73) and blank (1.00±0.00) control group ( all P ＜0. 01 ). The proliferation was lower, the activity of Caspase-3 was elevated and the apoptosis rates were significantly increased in miR-144 up-regulation group compared with negative and blank control group,while no significant difference was found between the latter 2 groups. Conclusion MiR-144 mimics may selectively up-regulate the expression of miR-144 in myocardial cells and consequently promote apoptosis and inhibit proliferation in myocardial cells.     

Bcl-2家族对细胞凋亡的作用及其在胰腺癌中的表达

Bcl-2基因是最早被发现与细胞凋亡有关的调控基因之一。Bcl-2家族中促进凋亡和抑制凋亡成员形成的二聚体结构对凋亡前的信号传导起重要作用。Bcl-2家族在胰腺癌组织中表达失调，且此现象与细胞凋亡和胰腺癌转移等表现相关。     

Bcl-2家族对细胞凋亡的作用及其在胰腺癌中的表达

Bcl-2基因是最早被发现与细胞凋亡有关的调控基因之一。Bcl-2家族中促进凋亡和抑制凋亡成员形成的二聚体结构对凋亡前的信号传导起重要作用。Bcl-2家族在胰腺癌组织中表达失调,且此现象与细胞凋亡和胰腺癌转移等表现相关。     

Bcl-2和Bax在胃癌中的表达及其意义

背景：细胞凋亡异常在肿瘤发生中起重要作用,抑凋亡基因Bcl-2和促凋亡基因Bax与细胞凋亡密切相关。目的：探讨Bcl-2和Bax在胃癌中的表达及其意义。方法：采用免疫组化SP法检测30例慢性非萎缩性胃炎、30例慢性萎缩性胃炎和30例胃癌黏膜组织中Bcl-2和Bax表达水平。结果：慢性非萎缩性胃炎组Bcl-2和Bax表达阳性率与慢性萎缩性胃炎组相比无明显差异（Bcl-2：36．7％对43．3％,Bax：33．3％对50．0％,P〉0．05）,但均显著低于胃癌组（分别为66．7％和80．0％,P〈0．05）。结论：Bcl-2和Bax在胃癌中的表达明显增加,提示两者可能在胃癌的发生、发展中起重要作用。     

螺内酯和缬沙坦对高血压大鼠心肌细胞凋亡相关蛋白的影响

目的探讨螺内酯和缬沙坦对肾血管性高血压大鼠左心室细胞凋亡调控相关蛋白P53、Bax及Bcl-2表达的影响。方法选取SD大鼠46只制成肾血管性高血压大鼠模型后,随机分为高血压组(N组,12只)、缬沙坦组(V组,11只)、螺内酯组(S组,12只)、螺内酯加缬沙坦组(S+V组,11只),另选10只未造模大鼠为假手术组(C组),各组治疗10周后行超声心动图检查,测定大鼠颈动脉压,应用免疫组织化学法检测P53、Bax及Bcl-2蛋白的表达。结果治疗10周后,与C组比较,N组大鼠收缩压明显升高(P0.01);与N组比较,V组、S+V组大鼠收缩压明显降低(P0.05);与C组比较,N组大鼠Bax、Bcl-2和Bax/Bcl-2明显升高,S组大鼠Bax和Bax/Bcl-2明显升高(P0.05,P0.01);与N组比较,S组大鼠Bax、Bax/Bcl-2和V组、S+V组大鼠Bax、Bcl-2、Bax/Bcl-2均明显下降(P0.05,P0.01);与S组比较,V组、S+V组大鼠Bax、Bax/Bcl-2明显下降(P0.05,P0.01)。结论两肾一夹肾血管性高血压大鼠左心室肥厚形成过程中,Bax过表达不完全依赖P53调节。缬沙坦可以通过与血管紧张素Ⅱ1型受体结合,抑制心肌细胞凋亡相关蛋白P53、Bax及Bcl-2的表达及左心室肥厚的发生。螺内酯可以通过与醛固酮受体结合明显降低P53及Bax的表达,降低Bax/Bcl-2比值,部分地逆转左心室肥厚。     

冠心康对高同型半胱氨酸血症兔主动脉Bcl-2蛋白表达的影响

目的探讨高同型半胱氨酸血症(Hhcy)致动脉粥样硬化(AS)时兔主动脉Bcl-2的变化及中药冠心康的防治作用。方法30只健康雄性新西兰大白兔,随机分3组:对照组,模型组,干预组,每组10只,喂食高蛋氨酸饲料方法建立兔Hhcy模型。用循环酶法检测同型半胱氨酸(Hcy)的含量、总胆固醇(TC)、甘油三酯(TG)、高密度脂蛋白胆固醇(HDL-C)、低密度脂蛋白胆固醇(LDL-C)含量。8周时动物处死,免疫组织化学方法检测兔主动脉Bcl-2蛋白的表达。结果冠心康在降低Hcy的同时,也降低TC、TG、LDL-C的含量(P<0.01),升高了HDL-C,能促进Bcl-2蛋白的表达(P<0.01)。结论冠心康可以抑制内皮细胞的凋亡,对AS的发生发展可起预防和治疗作用。     

胸腺瘤伴重症肌无力患者瘤组织中Bcl-2和Fas的表达水平

目的 探讨凋亡相关基因bcl-2、Fas在胸腺瘤伴重症肌无力患者瘤组织中的表达状况及其临床意义。方法经手术治疗的25例胸腺瘤伴重症肌无力患者的肿瘤组织标本为病例组，25例先天性心脏病患者手术时切取的正常胸腺组织标本为对照组，通过免疫组化的方法检测两组标本中Bcl-2和Fas蛋白的表达水平。结果胸腺瘤中Bcl-2及Fas表达水平均显著高于对照组，经Ridit分析两者差异均有统计学意义（U值分别为2．645、3．200，P均〈0．05），但Bcl-2和Fas的表达水平与胸腺瘤患者的重症肌无力Ossermen分型、术前病程、年龄及性别等临床因素均无显著相关。结论 Bcl-2和Fas在胸腺瘤伴重症肌无力的发病中可能具有重要作用。     

氟对软骨细胞凋亡因子bcl-2和Bax蛋白表达的影响

目的 观察氟对体外培养软骨细胞中凋亡相关因子bcl-2和Bax蛋白表达的影响,探讨氟在致软骨细胞凋亡中的作用机制.方法 采用软骨细胞体外培养方法,原代培养乳鼠关节软骨细胞,传第3代后按染氟剂量不同分为0(对照)、5、20、40mg/L组,培养10 d后,透射电镜下观察软骨细胞的超微结构改变,采用Western印迹法检测软骨细胞bcl-2和Bax蛋白表达.结果 透射电镜下,对照组和5 mg/L组软骨细胞呈球形,粗面内质网发达,线粒体膜性结构完整;20、40 mg/L组软骨细胞内可见脂滴增多,胞质内出现大量空泡类物质,细胞内膜结构不清,部分细胞出现核固缩.20、40 mg/L组软骨细胞bcl-2蛋白表达(0.626±0.042、0.531±0.039)较对照组(0.876±0.035)明显降低(P均＜0.01);而Bax蛋白表达(0.966±0.047、1.289±0.156)较对照组(0.642±0.050)明显增加(P均＜0.01).5 mg/L组软骨细胞bcl-2、Bax蛋白表达(0.885±0.065、0.657±0.045)与对照组比较,差异无统计学意义(P均＞0.05).此外,40 mg/L组与20 mg/L组比较,bcl-2、Bax蛋白表达差异有统计学意义(P均＜0.01).结论 染氟20、40 mg/L可对软骨细胞超微结构造成损伤,其通过减少抑凋亡因子bcl-2的表达和增加促凋亡因子Bax的表达,从而产生促进软骨细胞凋亡的作用.

Abstract：

Objective To study the effect of fluoride on the expression of bcl-2 and Bax in chondrocyte in vitro, and investigate the mechanism of action of chondrocyte apoptosis induced by fluoride. Methods Articular chondrocytes of neonate rat were cultured in vitro and treated with 0(control),5,20,40 mg/L of fluoride,respectively, for 10 days. Then observed the u]trastructure of chondrocytes under eletronicmicroscope, and tested the expression of bcl-2 and Bax in chondrocyte in different groups by Western blotting. Results Abundant rough endoplasmic reticulums (RERs) and complete structure of mitochondria membranes were presented in globular chondrocytes in the control group and 5 mg/L group; but more lipid droplets and vacuoles were seen in the cytoplasm, and the structure of intracellular membranes became incomplete, and some shrieked chromatin and pyknosis were seen in the chondrocytes of the 20,40 mg/L groups. The expression of bcl-2 markedly decreased in 20 mg/L group(0.626 ± 0.042) and 40 mg/L group(0.531± 0.039) compared to the control group(0.876 ± 0.035,all P ＜ 0.01 ). And the expression of Bax significantly increased in 20 mg/L group(0.966 ± 0.047) and 40 mg/Lgroup ( 1 .289 ± 0.156) compared to the control group(0.642 ± 0.050, all P ＜ 0.01). But there was no statistical significant difference of the expression of bcl-2 or Bax between 5 mg/L group(0.885 ± 0.065,0.657 ± 0.045) and control group (all P ＞ 0.05 ). However there were statistical differences of expressions of bcl-2 and Bax between 20 and 40 mg/L groups(all P ＜ 0.01 ). Conclusions Twenty and 40 mg/L fluoride can cause damage to the ultrastructure of chondrocyte, and fluoride possibly promotes chondrocyte apoptosis by reducing the expression of antiapoptotic factor bcl-2 and increasing the expression of Bax.     

预处理对老年鼠脑缺血bcl-2表达及细胞凋亡的影响

目的观察缺血预处理对脑缺血再灌注损伤的保护作用。方法将SD老年大鼠分为2组缺血预处理10min再灌注24h再次缺血24h组(PI)及单纯缺血对照组(CI),采用尼龙线栓法制作大鼠局灶性脑缺血模型,通过免疫组化染色技术及原位末端标记技术(TUNEL)检测大鼠大脑皮质bcl-2蛋白的表达和细胞凋亡情况。结果PI组较CI组缺血皮层bcl-2蛋白表达明显增强(P<0.01)。PI组缺血皮层凋亡细胞较CI组明显减少(P<0.05)。结论缺血预处理使缺血脑组织bcl-2蛋白表达增强,抑制凋亡细胞产生,说明缺血预处理对再次脑缺血有保护作用。     

自身免疫性甲状腺疾病甲状腺组织中bcl-2家族蛋白的表达

目的研究凋亡相关基因bcl鄄2家族蛋白bcl鄄2、mcl鄄1、bcl鄄XL和bax在自身免疫性甲状腺疾病(AITD)甲状腺组织中的表达特征及与AITD发病机制之间的内在联系。方法以甲状腺腺瘤旁正常甲状腺组织为对照(C组,20例),采用免疫组织化学ElivisionTM二步染色法检测凋亡相关蛋白bcl鄄2、mcl鄄1、bcl鄄XL和bax在桥本甲状腺炎(HT组,33例)和Graves病(GD组,28例)患者甲状腺组织中的表达与分布。结果bcl鄄2蛋白表达强度GD组>C组>HT组(P<0.01);mcl鄄1蛋白表达强度GD组>C组>HT组(P<0.01);bcl鄄XL蛋白表达强度HT组和GD组强于C组(P<0.01),但HT组和GD组间差异无统计学意义(P>0.05);bax蛋白的表达强度HT组>GD组和C组(P<0.01),但GD组和C组间差异无统计学意义(P>0.05);HT组中,在淋巴细胞浸润区域附近的甲状腺滤泡上皮细胞(TEC)bcl鄄2表达弱,bax和mcl鄄1表达强;远离淋巴细胞浸润区域的TECbcl鄄2表达强,bax和mcl鄄1表达弱(P<0.05)。结论(1)抗凋亡bcl鄄2和mcl鄄1蛋白在HT中表达的减弱以及在GD中表达的增强对于HT甲状腺滤泡细胞凋亡的增加和GD甲状腺滤泡细胞的增殖可能起一定作用;(2)bax蛋白在HT中表达增强所起的促凋亡的作用对疾病的发生发展起一定作用;(3)bcl鄄2与bax表达强度的比值对于凋亡的调控起重要作用;(4)bcl鄄2家族蛋白bc     

雷公藤甲素与地塞米松对哮喘豚鼠不同密度嗜酸粒细胞凋亡及bcl-2 mRNA表达的影响

目的　观察雷公藤甲素(TP)与地塞米松(DM)对体外不同密度嗜酸粒细胞(Eos)凋亡及 bcl 2mRNA表达的影响,探讨其促进哮喘Eos凋亡的机制。方法　卵蛋白激发哮喘豚鼠动物模型 48 小时后行支气管肺泡灌洗,分离不同密度 Eos。TP(10-7 ~10-4 mol/L) 或 DM(10-10 ~10-5 mol·L-1 )干预 24 小时,原位杂交检测Eos的bcl 2 mRNA表达,TUNEL法检测细胞凋亡。结果　TP及 DM干预 24 小时,可见Eos凋亡增加,以低密度Eos(HEos)为明显,bcl 2 mRNA表达降低,呈剂量依赖性。bcl 2 mRNA的表达与Eos凋亡呈负相关。结论　TP及DM可抑制 bcl 2 mRNA表达,促进 Eos凋亡。bcl 2 参与了 TP及DM对Eos凋亡的调节。TP可能具有激素样促进细胞凋亡的作用。     

替米沙坦对腹主动脉缩窄大鼠内质网应激相关的心肌细胞凋亡的影响

目的 探讨血管紧张素Ⅱ受体拮抗剂替米沙坦对腹主动脉缩窄术后大鼠内质网应激相关的心肌细胞凋亡的影响.方法 30只雄性SD大鼠随机分为假手术组(n=10),腹主动脉缩窄组(n=10),腹主动脉缩窄+替米沙坦组(n=10).术后10周各组大鼠用导管法测量血液动力学指标并留取心肌标本测左心室质量指数,心肌细胞凋亡用TUNEL法检测,心肌内质网应激信号通路分子GRP78、CHOP用免疫印迹法和免疫组化法检测.结果 (1)腹主动脉缩窄组左心室质量指数(3.29±0.19)mg/g明显高于假手术组(2.17±0.22)ms/g(P<0.01),左心室舒张末压(9.71±0.52)mm Hg(1 mm Hg=0.133 kPa)亦明显高于假手术组(2.79±0.13)mm Hg,左心室收缩末压(105.61 ±6.66)mm Hg明显低于假手术组(135.02 ±5.95)mm Hg(P<0.01),而腹主动脉缩窄+替米沙坦组上述指标分别为(2.34 ±0.08)mg/g、(4.70±0.36)mm Hg、(127.62 ±4.99)mm Hg,明显优于腹主动脉缩窄组(P<0.01).(2)腹主动脉缩窄+替米沙坦组心肌细胞凋亡指数(13.42 ±0.74)%显著低于腹主动脉缩窄组(35.51 ±0.65)%(P<0.01).(3)腹主动脉缩窄组内质网应激信号分子GRP78、CHOP蛋白表达RGRP78/β-actin 0.436 ±0.007、RCHOP/β-actin 0.747±0.034显著高于假手术组RGRP78/β-actin 0.144±0.009、RCHOP/β0.316 ±0.007(P<0.01),而腹主动脉缩窄+替米沙坦组GRP78、CHOP(RGP78/β-actin 0.213±0.007、RCHOP/β0.451 ±0.019),明显低于腹主动脉缩窄组(P<0.01).结论 内质网应激参与了腹主动脉缩窄术后大鼠心肌细胞凋亡,替米沙坦对内质网应激相关的心肌细胞凋亡有保护作用.     

C反应蛋白对人内皮细胞凋亡相关基因Bcl-2/Bax表达的影响

目的观察C反应蛋白(CRP)对体外培养人脐静脉内皮细胞(HUVEC)凋亡相关基因及蛋白Bcl-2／Bax表达的影响。方法采用酶消化法培养人脐静脉内皮细胞,将CRP(浓度为0、1、5、25 mg／L)与内皮细胞作用24 h后通过流式细胞仪测定凋亡细胞比率。选用25 mg／L CRP作用内皮细胞(0、4、8 h),采用逆转录-聚合酶链反应(RT-PCR)、Western-Blotting方法观察凋亡相关基因及蛋白Bcl-2／Bax表达的变化。结果随CRP浓度的增加诱导内皮细胞凋亡的比率逐渐增加,与对照组(5．42±0．92)％相比,25 mg／L时细胞凋亡率达(15．71±2．34)％,显著增加(P<0．01);内皮细胞在25 mg／L CRP作用4、8 h后Bax mRNA、蛋白表达逐渐增强,Bcl-2 mRNA、蛋白表达逐渐减弱,在8 h它们表达量与对照组相比差异有统计学意义(P<0．05)。结论临床相关浓度的CRP可通过调节Bcl- 2／Bax mRNA、蛋白的表达诱导内皮细胞凋亡。     

Nicorandil regulates Bcl-2 family proteins and protects cardiac myocytes against hypoxia-induced apoptosis

Nicorandil has been shown to inhibit myocyte apoptosis by opening of mitochondrial ATP-sensitive potassium (mitoK(ATP)) channels and nitrate-like effect against oxidative stress. However, the detailed mechanism of nicorandil-mediated cardioprotection under hypoxic conditions remains to be largely unknown. The present study examined whether nicorandil can inhibit apoptosis via regulation of Bcl-2 family proteins in hypoxic myocytes. Neonatal rat cardiac myocytes were exposed to hypoxia for 7 hours. Hypoxia-induced myocyte apoptosis (13.9+/-0.9%) under glucose-rich conditions. Myocyte apoptosis was accompanied by loss of mitochondrial membrane potential (Deltapsi(m)), cytochrome c release from mitochondria into cytosol, and activation of caspase-3. Hypoxia also significantly increased Bax and decreased Bcl-2 mRNA and protein expression, thereby increasing Bax/Bcl-2 ratio. Nicorandil 100 micromol/l significantly decreased the percentage of apoptotic myocytes (7.2+/-0.5%) by inhibiting loss of Deltapsi(m) and translocation of cytochrome c. These effects of nicorandil were partially but significantly inhibited by cotreatment of either 500 micromol/l 5-hydroxydecanoate, a selective mitoK(ATP) channel antagonist, or 10 micromol/l 1H-[1,2,4]oxidazolo[4,3-a]quinoxalin-1-one (ODQ), an inhibitor of soluble guanylate cyclase. Moreover, nicorandil significantly inhibited the hypoxia-induced changes in Bax and Bcl-2 expression, and concomitant increased Bax and decreased Bcl-2 immunoreactivity in mitochondria. These effects of nicorandil in Bax and Bcl-2 expression were significantly blunted by cotreatment of ODQ and 5-HD, respectively. Cotreatment of KT5823, an inhibitor of protein kinase G, significantly blocked the effect of nicorandil on Bax expression and 8-bromo-cyclic guanosine 3',5' monophosphate (8-bromo-cGMP), a cGMP analog, mimicked the effect of nicorandil on Bax expression. The present study demonstrates that nicorandil regulates Bcl-2 family proteins via opening of mitoK(ATP) channels and nitric oxide-cGMP signaling and inhibits hypoxia-induced mitochondrial death pathway.     

肝纤维化大鼠肝脏Bcl-2、Bax、增殖细胞核抗原的表达及重组转化生长因子β1疫苗对其表达的影响

目的观察肝纤维化大鼠肝脏Bcl-2、Bax、增殖细胞核抗原（PCNA）的表达及重组转化生长因子（TGF）-β1疫苗对其表达的影响，探讨肝细胞凋亡、增殖与肝纤维化的关系及重组TGF-β1疫苗对凋亡因子及PCNA表达的影响。方法将健康雄性Sprague-Dawley系大鼠30只分为正常组、肝纤维化模型组和TGF-β1疫苗治疗组，每组各10只。肝纤维化模型组以0．5％的二甲基亚硝胺（DMN）按0．2mL／100g的剂量腹腔内注射，TGF—β1疫苗治疗组在注射DMN的基础上，皮下注射疫苗150μg。42d后处死，分批从各组取血清、肝脏组织，采用S—P免疫组织化学方法检测Bcl-2、Bax和PCNA的表达，并检测血ALT、AST、AIb、HA及LN。结果Bax与大鼠肝脏病理分级呈正相关，Bob2、Bcl-2／Bax与大鼠肝脏病理分级呈负相关，PCNA与大鼠肝脏病理分级无明显相关性。正常组大鼠肝组织中TGF-β1、Bax表达水平较低，明显低于肝纤维化模型组（P〈0．01），Bcl-2表达水平与肝纤维化模型组相当，差异无统计学意义。但TGF-β1疫苗治疗组肝组织中TGF-β1表达明显下降，Bcl-2表达水平明显升高，与肝纤维化模型组相比，差异有统计学意义（P〈0．05），而Bax表达水平与肝纤维化模型组相当，差异无统计学意义。肝纤维化模型组PCNA的水平较正常组高，差异有统计学意义（P〈0．01），但TGF-β1疫苗治疗组PCNA的水平较肝纤维化模型组又明显提高，差异有统计学意义（P〈0．01）。结论肝细胞凋亡是引起肝纤维化的可能机制之一。TGF-β1疫苗可能通过影响肝纤维化大鼠Bcl-2、Bax、PCNA的表达而影响肝细胞的凋亡和增殖，从而改善肝脏病理分级。