大鼠心肌梗死后神经生长因子受体的表达

目的:观察大鼠心肌梗死(MI)后不同时间点(1 d、7 d、30 d)神经生长因子(NGF)受体的表达情况。方法:采用开胸结扎冠状动脉法建立大鼠MI模型,在术后1 d、7 d、30 d处死动物,取出心脏,假手术大鼠(只开胸不结扎)作为对照研究。分别用实时定量PCR方法及Western blot方法检测梗死边缘区心肌中高亲和性受体酪氨酸激酶A(Trk A)和低亲和力神经受体P75(P75NTR)mRNA及蛋白的表达。结果:与对照组相比,MI后1 d,7 d,30 d,P75NTR mRNA及蛋白表达都没有明显差异,Trk A mRNA及蛋白表达在MI后7 d及30 d较对照组明显下降(P0.05),而且呈动态下降趋势。结论:大鼠MI后心脏NGF受体Trk A和P75NTR的表达发生了变化,P75NTR表达程度在NGF介导的MI后交感神经增生中不起决定作用。     

参松养心胶囊对兔心肌梗死后神经重构的影响

目的探讨参松养心胶囊对心肌梗死(简称心梗)后神经重构的影响。方法新西兰大耳白兔行冠状动脉结扎术后随机分为心梗组、心梗+参松组(每公斤体重每天0.4 g)。假手术组开胸后在冠状动脉下穿线,但不结扎。术后8周,处死动物,从家兔梗死周边区及非梗死区取材。免疫组化研究生长相关蛋白(GAP43)及酪氨酸羟化酶(TH)阳性纤维的密度。逆转录聚合酶链式反映研究核因子(NF-κB)、内皮素-1(ET-1)、神经生长因子(NGF)、白细胞介-1β(IL-1β)、肿瘤坏死因子-α(TNF-α)及神经营养素受体P75(p75-NTR)mRNA的相对表达量。结果与假手术组(n=10)相比,心梗组(n=8)神经纤维密度显著增加,NF-κB、ET-1、NGF、IL-1β、TNF-α及p75-NTR的mRNA表达显著升高(P0.05)。与心梗组相比,心梗+参松组(n=9)神经纤维密度减少,NF-κB、ET-1、NGF、IL-1β、TNF-α及p75-NTR mRNA的表达降低(P0.05)。结论参松养心胶囊可以降低心梗后的神经密度,其作用机制可能与抑制炎症因子及NGF信号途径相关。     

Smad7的表达对心肌梗死后大鼠心肌纤维化的影响

目的研究心肌梗死（MI）后大鼠心肌Smad7的表达及其与心肌纤维化的关系。方法结扎冠状动脉建立大鼠MI模型,并另设假手术组为对照组。8周后,测定心室的质量/体质量（HW/BW）。以多普勒超声评价心脏功能。以Mallory’s Trichrome染色法检测非梗死区胶原的含量。分别以RT-PCR和Western blot法检测非梗死区左室心肌转化生长因子（TGF）-β1、Smad7 mRNA及蛋白表达的水平。结果与假手术组比较,MI组的HW/BW（P<0.01）、左心室舒张末期内径（LVEDD,P<0.01）、E峰/A峰比值（E/A,P<0.01）、非梗死区胶原的含量（P<0.01）、非梗死区左室TGF-β1mRNA及蛋白的表达（P<0.01）均显著增加;Smad7 mRNA及蛋白的表达（P<0.01）、射血分数（EF,P<0.01）及短轴缩短率（FS,P<0.01）均显著降低。结论MI后大鼠心肌Smad7的表达降低,与MI后的心肌纤维化密切相关。     

阿托伐他汀对急性心肌梗死大鼠交感神经重构的影响

目的:探讨阿托伐他汀对急性心肌梗死(AMI)大鼠交感神经重构的影响。方法:24只SD大鼠随机分为3组:A组(假手术组);B组(AMI合并血脂异常组);C组(阿托伐他汀干预组)。采用结扎冠状动脉前降支,结合喂饲高脂饮食制作AMI合并血脂异常模型,免疫组化法检测各组大鼠梗死周边区生长相关蛋白-43(GAP-43)和酪氨酸羟化酶(TH)阳性神经纤维分布和密度,Western blot方法检测神经生长因子(NGF)和白细胞介素-1β(IL-1β)蛋白表达。生化法检测氧化应激相关指标。结果:与A组比较,B组梗死周边区域GAP-43和TH阳性神经纤维密度明显增加(均P<0.05),NGF和IL-1β蛋白表达增加(均P<0.05),伴随氧化应激水平增高(P<0.05)。C组GAP-43和TH阳性神经纤维密度较B组显著减少(均P<0.05),伴随NGF、IL-1β蛋白表达降低(均P<0.05)及氧化应激状态的改善。结论:阿托伐他汀可有效的改善AMI合并血脂异常大鼠交感神经重构,其机制与氧化应激状态改善和NGF表达下调有关。     

ghrelin对糖尿病大鼠缺血诱导的血管新生障碍的影响及相关机制

目的 探讨生长激素促分泌物受体(GHSR)的内源性配体ghrelin对糖尿病大鼠缺血诱导的血管新生障碍的影响及相关机制.方法 选取7～8周龄的SD大鼠,用完全随机化法分为6组:(1)正常对照组,(2)单纯糖尿病组,(3)单纯心肌梗死(MI)组,(4)糖尿病合并MI组,(5)糖尿病合并MI+ ghrelin干预组,(6)糖尿病合并MI+ ghrelin+ GHSR1a特异性拮抗剂D-Lys3-GHRP-6干预组.建立链脲佐菌素(STZ)糖尿病大鼠模型,3个月后结扎冠状动脉左前降支建立急性MI模型.ghrelin干预组大鼠腹腔注射ghrelin(200 μg·kg-1·d-1),ghrelin+ D-Lys3-GHRP-6干预组大鼠腹腔注射ghrelin(200μg·kg-1·d-1)+ D-Lys3-GHRP-6(50 mg· kg-1·d-1),其余组别分别腹腔注射等量生理盐水.4周后超声心动图检测各组大鼠心功能,CD34免疫组织化学检测MI边缘区微血管生成密度(MVD),Masson染色检测MI面积,实时荧光定量-PCR和Western blot分别检测MI边缘区血管内皮细胞生长因子(VEGF)、血管内皮细胞生长因子受体1(Flt-1)和血管内皮细胞生长因子受体2(Flk-1)的mRNA及蛋白表达.结果 (1)与单纯MI组比较,糖尿病合并MI组梗死边缘区MVD[(15.3±1.0)个比(20.7±1.6)个,P＜0.05]、左心室射血分数(LVEF)[(64.2±3.4)％比(81.3±3.8)％,P＜0.01]、左心室短轴缩短率(LVFS)[(31.7±1.1)％比(48.8±3.3)％,P＜0.01]较低,MI面积较大[(55.8±3.1)％比(35.7 ±2.5)％,P＜0.01],梗死边缘区VEGF及其受体Flt-1、Flk-1的基因和蛋白表达差异均有统计学意义(P均＜0.001).(2)与糖尿病合并MI组比较,糖尿病合并MI+ghrelin干预组梗死边缘区MVD[(17.7±1.3)个比(15.3±1.0)个,P＜0.05]、LVEF[(83.9±6.3)％比(64.2±3.4)％,P＜0.001]、LVFS[(44.5±3.1)％比(31.7±1.1)％,P＜0.001]较大,MI面积较低[(35.4±4.37)％比(55.8±3.1)％,P =0.005],梗死边缘区VEGF及其受体Flt-1、Flk-1的基因和蛋白表达差异均有统计学意义(P ＜0.001).ghrelin+ D-Lys3-GHRP-6干预组大鼠MVD、LVEF、LVFS均较ghrelin干预组低(P均＜0.05),MI面积较大[(52.1±1.04)％比(35.4±4.37)％,P=0.02],梗死边缘区VEGF及其受体Flt-1、Flk-1基因与蛋白表达的效应较高(P均＜0.01).结论 糖尿病合并MI大鼠心肌梗死边缘区MVD和心功能较单纯MI大鼠低,MI面积大,ghrelin可能通过调控GHSR1a依赖的VEGF及其受体Flt-1、Flk-1基因和蛋白表达来提高糖尿病MI大鼠梗死边缘区MVD,进一步减少其梗死面积及改善心功能.     

Ⅱ型糖尿病大鼠心肌梗死后交感神经重构与神经生长因子(NGF)的表达改变

目的:探讨糖尿病并发心肌梗死(MI)对大鼠心肌中神经生长因子(NGF)的表达及交感神经再生重构的影响。方法:将实验大鼠分为正常对照组、糖尿病对照组、MI对照组及糖尿病MI组,从各组大鼠的左心室梗死周边、室间隔和右心室取材,通过免疫组化染色并结合计算机图像处理技术,对心肌中NGF蛋白表达及交感神经支配进行对比分析。结果:与正常对照组及糖尿病心梗组比较,MI对照组的NGF表达均增加(均P0.05),交感神经支配密度也均明显增加(均P0.01),并且二者在梗死周边、室间隔及右心室3个部位的表达存在相关性(均P0.05),糖尿病对照组的NGF表达均降低(P0.05,P0.01),交感神经支配密度分别为无明显差异及明显降低(P0.01)。结论:糖尿病可抑制心肌细胞表达NGF,但却可促进MI后交感神经的过度再生与重构。推测糖尿病条件下,NGF并非交感神经再生重构的决定因素,尚存在其他途径对交感神经再生及重构进行调节。     

美托洛尔对急性心肌梗死大鼠心肌神经生长因子表达和神经重构的影响

目的 探讨β受体阻滞剂美托洛尔对大鼠急性心肌梗死(AMI)后心肌神经生长因子(NGF)表达和交感神经再生的影响.方法 结扎大鼠左前降支,建立AMI模型,存活者随机分为美托洛尔治疗组(MI-B组,n=10)和梗死对照组(MI-C组,n=10),另设假手术组(S组,n=8).MI-B组给予4周美托洛尔治疗,MI-C组和S组给予同体积生理盐水静脉注射和灌胃,4周后检测梗死周边区和梗死远端心脏神经纤维分布和密度以及心肌NGF基因和蛋白表达的变化.结果 与S组相比,MI-C组梗死周边和梗死远端心肌组织中NGF基因和蛋白表达明显升高(P＜0.05),梗死周边和梗死远端神经支配密度增高(P＜0.01).与MI-C组比较,MI-B组心肌细胞内NGF表达明显下降(P＜0.05),神经支配密度亦明显下降(P＜0.01).结论 早期美托洛尔治疗AMI可以改善心肌NGF表达和交感神经再生.美托洛尔改善交感神经再生的作用机制至少部分与其降低神经生长因子的表达和释放作用有关.     

骨髓间充质干细胞移植对大鼠梗死心脏核因子KB活性的影响

目的观察骨髓间充质干细胞对心肌梗死的治疗效果，以及心肌梗死后炎症因子表达的影响，探讨其治疗心肌梗死的可能机制。方法提取SD大鼠骨髓间充质干细胞，体外培养、纯化扩增。采用结扎冠状动脉前降支方法复制大鼠心肌梗死模型，将建立的模型随机分为：1）假手术组（仅穿线不结扎血管，n=8）；2）PBS溶液注射组（n=8）；3）干细胞移植组（n=8）。模型制作成功即刻，将骨髓间充质干细胞通过心外膜分4点注射到梗死周边部位。4周后测定血流动力学指标。随后通过Western blot方法测定核因子KB活性，RT-PCR和western blot法测定肿瘤坏死因子α、白介素6 mRNA和蛋白表达。结果1）4周后，假手术组大鼠死亡率20％（2／10），治疗阴性对照组大鼠死亡率33．3％（4／12），干细胞移植组大鼠死亡率20％（2／10），3组死亡率没有统计学差异（P=0．646）；2）与注射PBS溶液相比，骨髓间充质干细胞移植可以改善心肌梗死大鼠血流动力学指标；3）骨髓间充质干细胞可以抑制大鼠梗死心肌核因子kB活性，下调肿瘤坏死因子α和白介素6 mRNA和蛋白表达水平。结论骨髓间充质干细胞可以改善心肌梗死大鼠的心功能，同时可调节大鼠梗死心脏炎症反应。     

左旋精氨酸对急性心肌梗死大鼠血管新生的影响及心肌保护作用

【目的】 观察左旋精氨酸干预对急性心肌梗死（AMI）大鼠心肌梗死边缘区血管新生的影响及其心肌保护作用。【方法】 冠状动脉结扎法建立大鼠AMI模型,30只SD雄性大鼠被随机分为三组：假手术组,生理盐水对照组及左旋精氨酸干预组。在冠状动脉结扎后4周,超声心动图测量大鼠心脏左室舒张末内径（LVEDD）、左室收缩末内径（LVESD）、左室射血分数（LVEF）、左室短缩分数（LVFS）,Masson染色测定梗死面积,ELISA法检测各组大鼠血浆脑钠尿肽（BNP）水平;采用免疫组织化学技术检测大鼠心肌梗死边缘区CD31阳性的内皮细胞数量及 -SMA阳性平滑肌细胞数量,以评估新生血管情况,Western blot检测梗死边缘区内皮型一氧化氮合成酶（eNOS）及胶原-1蛋白含量。【结果】 冠状动脉结扎后4周,与对照组相比,左旋精氨酸干预组LVEF、LVFS明显升高,而LVEDD及LVESD降低（P<0.01）,且梗死面积明显缩小（P<0.01）,血浆BNP水平亦较低（P<0.01）,而梗死边缘区CD31阳性的内皮细胞及 -SMA阳性平滑肌细胞密度则高于对照组（P<0.01）,梗死周围区eNOS蛋白水平高于对照组,而胶原-1蛋白含量则低于对照组（P<0.01）。【结论】 左旋精氨酸干预可促进AMI大鼠梗死心肌边缘区毛细血管及小动脉新生,减少胶原-1蛋白含量,促进eNOS的表达,并可达到改善左心收缩功能、降低血浆BNP水平、缩小梗死面积的心肌保护作用。     

急性心肌梗死大鼠心脏一氧化氮合酶表达的改变

目的 通过建立大鼠心肌梗死模型，观察急性心肌梗死对大鼠心脏内皮型一氧化氮合酶mRNA和诱导型一氧化氮合酶蛋白表达的影响。方法48只健康成年SD大鼠（体重200～250g）随机分为假手术组和缺血组，取1、2、8和24h四个不同时间点观察。采用开胸结扎冠状动脉左前降支建立心肌缺血模型，逆转录聚合酶链反应检测大鼠心肌梗死后1、2及24h三个时段缺血心肌内皮型一氧化氮合酶mRNA的表达；免疫组织化学染色检测冠状动脉结扎后8h缺血心肌诱导型一氧化氮合酶蛋白的表达。结果冠状动脉结扎后2h，缺血组大鼠缺血心肌组织内皮型一氧化氮合酶mRNA表达下降（P〈0．05），并持续至结扎后24h；结扎后24h组内皮型一氧化氮mRNA的表达与结扎后2h组相比无显著性差异（P〉0．05）。冠状动脉结扎后8h，梗死区存活心肌组织细胞诱导型一氧化氮合酶蛋白大量表达，而假手术组未见诱导型一氧化氮合酶蛋白表达。结论正常大鼠心肌组织有内皮型一氧化氮合酶基因表达，无诱导型一氧化氮合酶蛋白表达。在心肌梗死早期缺血心肌内皮型一氧化氮合酶mRNA表达减少。心肌急性缺血刺激早期诱导大鼠缺血心肌组织诱导型一氧化氮合酶蛋白大量表达。     

Mechanisms of cardiac nerve sprouting after myocardial infarction in dogs

Cardiac nerve sprouting and sympathetic hyperinnervation after myocardial infarction (MI) both contribute to arrhythmogenesis and sudden death. However, the mechanisms responsible for nerve sprouting after MI are unclear. The expression of nerve growth factor (NGF), growth associated protein 43 (GAP43), and other nerve markers were studied at the infarcted site, the noninfarcted left ventricle free wall (LVFW), and the left stellate ganglion (LSG) at several time points (30 minutes to 1 month) after MI. Transcardiac (difference between coronary sinus and aorta) NGF levels were also assayed. Acute MI resulted in the immediate elevation of the transcardiac NGF concentration within 3.5 hours after MI, followed by the upregulation of cardiac NGF and GAP43 expression, which was earlier and more pronounced at the infarcted site than the noninfarcted LVFW. However, cardiac nerve sprouting and sympathetic hyperinnervation were more pronounced in the noninfarcted than the infarcted LVFW site and peaked at 1 week after MI. The NGF and GAP43 protein levels significantly increased in the LSG from 3 days (P<0.01 for all) after MI, without a concomitant increase in mRNA. There was persistent elevation of NGF levels in aorta and coronary sinus within 1 month after MI. We conclude MI results in immediate local NGF release, followed by upregulation of NGF and GAP43 expression at the infarcted site. NGF and GAP43 are transported retrogradely to LSG, which triggers nerve sprouting at the noninfarcted LVFW. A rapid and persistent upregulation of NGF and GAP43 expression at the infarcted site underlies the mechanisms of cardiac nerve sprouting after MI.     

心肌梗死后神经生长因子的动态表达及其与交感神经重构的关系

目的 探讨心肌梗死后心肌中神经生长因子(NGF)的动态表达及其在交感神经重构中的作用。方法 从心肌梗死大鼠的梗死周边、室间隔和右心室取材,通过免疫组化染色并结合计算机图像处理技术对心肌中NGF蛋白表达及交感神经支配进行研究。结果 心肌梗死后3天,NGF蛋白的表达在梗死周边心肌中明显减少(P<0.05),在室间隔和右心室中增加;交感神经支配密度在梗死周边和室间隔中明显降低,在右心室中明显增加(P<0.05);室间隔和右心室中交感神经支配与NGF蛋白的表达相关(P<0.05)。心肌梗死后7天,梗死周边心肌中NGF蛋白的表达与交感神经支配密度相关(P<0.01),并均明显高于假手术组(P<0.05)及心肌梗死后3天组(P<0.01);室间隔和右心室中NGF蛋白的表达、交感神经支配密度及范围均明显高于假手术组。心肌梗死后30天,NGF蛋白的表达在梗死周边和室间隔中略有降低,交感神经支配范围及密度在各处心肌中均明显高于心肌梗死后3天、7天(P<0.01)。结论 心肌梗死后心肌中NGF蛋白的表达具有动态过程,并与交感神经失支配、再生和过度支配相关,提示NGF可能在心肌局部发挥神经营养作用进而参与神经重构及神经内分泌的调节过程。     

生长素释放肽对急性肺损伤小鼠核因子κB和纤溶系统的干预作用

目的 探讨生长素释放肽(Ghrelin)对盲肠结扎穿孔(CLP)介导的急性肺损伤小鼠早期核因子κB(NF-κB)和纤溶系统的影响.方法 将32只昆明小鼠随机分为正常组、假手术组、CLP组和Ghrelin干预组,Ghrelin干预组在CLP后5 h、10 h、15 h时间段分次腹腔注射Ghrelin(共40 nmol/kg).采用HE染色进行病理检测,免疫组织化学方法检测NF-κB表达,采用酶联免疫吸附试验方法检测血浆纤溶酶原激活物抑制因子-1(PAI-1)、组织型纤溶酶原激活物(t-PA)水平,计算t-PA/PAI-1比值.结果 ①病理结果显示:与正常组、假手术组相比,CLP组部分肺泡结构受到破坏,大量炎症细胞浸润,间质水肿明显,部分有出血,Ghrelin干预组肺组织病理损伤程度明显减轻.②免疫组织化学结果显示:与正常组、假手术组相比,CLP组肺组织NF-κB表达显著增强.Ghrelin干预组的NF-κB表达强度比CLP组弱.③与正常组、假手术组相比,CLP组PAI-1、t-PA水平明显升高(P<0.01),t-PA/PAI-1比值明显下降(P<0.01).Ghrelin干预组的血浆PAI-1水平较CLP组明显下降(P<0.01),血浆t-PA水平较CLP组轻度升高(P<0.05),t-PA/PAI-1比值较CLP组明显升高(P<0.01).结论 急性肺损伤小鼠早期纤溶系统功能抑制,Ghrelin可以降低CLP所致肺组织NF-κB的表达,Ghrelin可能通过NF-κB途径减轻CLP介导的急性肺损伤,提高纤溶活性.     

Interaction Between AT1 Receptor and NF-κB in Hypothalamic Paraventricular Nucleus Contributes to Oxidative Stress and Sympathoexcitation by Modulating Neurotransmitters in Heart Failure

Angiotensin II type 1 receptor (AT1-R) and nuclear factor-kappaB (NF-κB) in the paraventricular nucleus (PVN) play important roles in heart failure (HF); however, the central mechanisms by which AT1-R and NF-κB contribute to sympathoexcitation in HF are yet unclear. In this study, we determined whether interaction between AT1-R and NF-κB in the PVN modulates neurotransmitters and contributes to NAD(P)H oxidase-dependent oxidative stress and sympathoexcitation in HF. Rats were implanted with bilateral PVN cannulae and subjected to coronary artery ligation or sham surgery (SHAM). Subsequently, animals were treated for 4 weeks through bilateral PVN infusion with either vehicle or losartan (LOS, 10 μg/h), an AT1-R antagonist; or pyrrolidine dithiocarbamate (PDTC, 5 μg/h), a NF-κB inhibitor via osmotic minipump. Myocardial infarction (MI) rats had higher levels of glutamate (Glu), norepinephrine (NE) and NF-κB p65 activity, lower levels of gamma-aminobutyric acid (GABA), and more positive neurons for phosphorylated IKKβ and gp91^phox (a subunit of NAD(P)H oxidase) in the PVN when compared to SHAM rats. MI rats also had higher levels of renal sympathetic nerve activity (RSNA) and plasma proinflammatory cytokines (PICs), NE and epinephrine. PVN infusions of LOS or PDTC attenuated the decreases in GABA and the increases in gp91^phox, NF-κB activity, Glu and NE, in the PVN of HF rats. PVN infusions of LOS or PDTC also attenuated the increases in RSNA and plasma PICs, NE and epinephrine in MI rats. These findings suggest that interaction between AT1 receptor and NF-κB in the PVN contributes to oxidative stress and sympathoexcitation by modulating neurotransmitters in heart failure.     

Ghrelin inhibits IKKβ/NF-κB activation and reduces pro-inflammatory cytokine production in pancreatic acinar AR42J cells treated with cerulein

Background: Previous studies have provided conflicting results regarding whether the serum ghrelin concentration can reflect the severity of acute pancreatitis(AP). The present study examined the correlation between the serum ghrelin concentration and AP severity in animal models and investigated whether altered ghrelin expression in pancreatic acinar cells influences IKK β/NF-κ B signaling and pro-inflammatory cytokine production. Methods: Mild or severe AP was induced in rats by intraperitoneal injection of cerulein or retrograde cholangiopancreatic duct injection of sodium taurocholate, respectively. After successful model induction, serum ghrelin, tumor necrosis factor-α(TNF-α), and interleukin-6(IL-6) concentrations were determined by enzyme-linked immunosorbent assay, and IKK β/NF-κ B activation was assessed by immunohistochemistry. Subsequently, stable overexpression or knockdown of ghrelin in AR42 J cells was achieved by lentiviral transfection. After transfected cells and control cells were treated with cerulein for 24 h, the TNF-αand IL-1 β levels in the supernatants were determined by enzyme-linked immunosorbent assay, and the expression levels of p-p65, IKK β, and p-IKK β were detected by Western blotting. Results: In rat AP models, AP severity was correlated with increased IKK β/NF-κ B activation, proinflammatory cytokine production, and ghrelin secretion. The levels of pro-inflammatory cytokines TNF-αand IL-1 β as well as IKK β/NF-κ B signaling activity were increased upon knockdown of ghrelin in the AP acinar cell model and decreased with ghrelin overexpression. Conclusions: Serum ghrelin is related to the severity of AP. Ghrelin may play a protective role in the pathogenesis of AP by inhibiting the pro-inflammatory cytokines and the activation of the IKK β/NF-κ B signaling pathway.     

外源性神经生长因子对雪旺细胞中NF-κB mRNA 表达的影响

目的：观察外源性神经生长因子（NGF）对雪旺细胞（SCs）中核转录因子κB（NF-κB）mRNA表达的影响。方法体外培养SCs，用S-100免疫组化染色鉴定细胞纯度。取第4代优质细胞，随机分为实验组（ NGF）、阻断组（NGF＋anti-NGFR）、对照组（PBS），提取各组总mRNA，分别用紫外分光光度计、1．5％琼脂糖凝胶电泳观察结果，通过实时荧光定量PCR检测NF-κB mRNA的表达。结果体外培养的SCs与倒置显微镜下观察到的活体细胞形态一致，S-100免疫组化染色显示，SCs纯度达到91％。紫外分光光度计观察A260/A280为1．8～2．2，1．5％琼脂糖凝胶电泳可见28、18 s两条清晰条带，证实提取的mRNA质量良好。实时荧光定量PCR检测发现，与对照组、阻断组相比，实验组NF-κB mRNA的表达显著增高（P均＜0．01）。结论外源性NGF可以上调SCs中NF-κB mRNA的表达。     

Involvement of visfatin in palmitate-induced upregulation of inflammatory cytokines in hepatocytes

Free fatty acids (FFAs) lead to the activation of inflammatory pathways related to the induction of insulin resistance. Visfatin is known to play a role in obesity-related metabolic diseases and inflammatory conditions. Here, the role of visfatin in FFA-induced inflammation was investigated in hepatocytes. The following factors were examined: (1) the protein and messenger RNA (mRNA) expression of visfatin in the liver tissue of insulin-resistant rats and in (2) in HepG2 cells treated with palmitate, (3) the palmitate-induced mRNA expression and protein synthesis of interleukin-6 and tumor necrosis factor-α in HepG2 cells transfected with visfatin-specific small interfering RNA, and (4) the expression of visfatin in HepG2 cells treated with a nuclear factor-κB (NF-κB) inhibitor (SN50) and infected with Ad-IκBα. The protein and mRNA levels of visfatin were significantly higher in insulin-resistant rat liver tissue compared with the control group. Visfatin expression and protein synthesis significantly increased in HepG2 cells treated with palmitate in a time- and concentration-dependent manner. Visfatin-specific small interfering RNA significantly decreased the palmitate-induced mRNA expression and protein synthesis of interleukin-6 and tumor necrosis factor-α. A NF-κB inhibitor induced the downregulation of visfatin in HepG2 cells following treatment with palmitate. HepG2 cells infected with Ad-IκBα showed decreased expression of visfatin following treatment with palmitate. The expression of visfatin is closely associated with the expression of proinflammatory cytokines in FFA-induced inflammation and is significantly decreased by NF-κB inhibition in HepG2 cells. Visfatin may play a role in FFA-induced inflammation in hepatocytes through the NF-κB pathway.     

急性心肌梗死后心衰大鼠核因子-κB与炎性细胞因子的相关性研究

目的:探讨急性心肌梗死后（AMI）心衰(HF)大鼠血清核因子-κB（NF-κB）的水平与肿瘤坏死因子-α（TNF-α）、高敏C反应蛋白（hsCRP）分泌的相关性。方法: 将50只SD大鼠随机分为3组:HF组（20只）、治疗组（20只）和假手术组（10只）。结扎大鼠冠状动脉前降支建立AMI后HF模型。治疗组在手术结扎后饮水中给予NF-κB抑制剂吡咯烷二硫代氨基甲酸盐(pyrrolidine dithiocarbamate,PDTC),HF组和假手术组给予同等量的蒸馏水。术后6周,行血流动力学检测;秤取心脏组织的湿质量;取动脉血分离血清,用ELISA法检测NF-κB、TNF-α的水平,用乳胶增强透射免疫比浊法检测hsCRP水平。结果: ①HF组和治疗组大鼠心室重构指数和肺指数明显高于假手术组（P<0.05）。②HF组和治疗组大鼠血流动力学的状况较假手术组明显下降（P<0.05）,但治疗组较HF组有所好转（P<0.05）。③HF组和治疗组血清NF-κB、TNF-α和hsCRP的水平较假手术组明显升高（P<0.05）;治疗组又较HF组明显下降（P<0.05）。④NF-κB的水平与TNF-α、hsCRP的水平呈显著的正相关（r分别为0.465和0.323,均P<0.05）。结论: AMI后HF大鼠血清NF-κB的水平升高,炎性细胞因子TNF-α和hsCRP分泌增多,HF大鼠可能是通过NF-κB水平的升高上调炎性细胞因子的分泌。