RNA阵列技术检测自发性高血压大鼠甲羟戊酸途径酶的基因表达

目的：探讨甲羟戊酸(MVA)途径的9个酶在不同周龄自发性高血压大鼠(SHR)发病过程中的基因表达变化特点。方法:提取2、4、6、8、10、12不同周龄雄性SHR以及正常血压大鼠(WKY)的心室肌、血管平滑肌、肝脏和肾脏4种组织的总RNA，共294个样品，利用高通量RNA阵列技术(RNA array)检测甲羟戊酸途径的9个酶的基因在不同周龄SHR和WKY大鼠中mRNA表达谱的改变。 结果:（1）SHR大鼠从第6周开始收缩压明显高于WKY(P<0.01)。 （2）12周龄SHR大鼠体内血清胆固醇浓度明显低于WKY大鼠，组织中的胆固醇浓度没有明显差异(P<0.01)。（3）在SHR大鼠心脏、血管、肝脏、肾脏组织中：MVA中间产物的合成酶如法呢醇焦磷酸合成酶(FDS)、异戊烯化焦磷酸化异构酶(IDI)、法呢醇转移酶α亚基(FT1)和β亚基(FT2)的表达明显高于WKY(P<0.01)。（4）SHR肾脏组织中羟甲基戊二酰辅酶A还原酶（HMGR）、甲羟戊酸激酶（MVK）、焦磷酸甲羟戊酸脱羧酶（MVD）、鲨烯合成酶（SQS）和鲨烯环氧化酶（SQ） 表达较为一致，早期(2-4 周)SHR大鼠的基因表达明显高于WKY，随着周龄增加SHR的表达进一步增高，且与WKY相比都有明显差异(P<0.01) 。（5）在心脏、血管和肝脏中，HMGR、MVK、MVD、SQS和SQ的基因表达无明显规律。结论:SHR大鼠随着周龄的增长甲羟戊酸途径中各酶基因表达的改变，以非胆固醇产物类合成酶(如IDI、FDS和FT1、FT2)表达增加为特点，这一改变是否与高血压有关尚待进一步验证。     

新的高血压相关基因－Slc7a8的实验研究

目的：探讨高血压致病相关基因。方法: 提取13周龄SHR和WKY的2、3级肠系膜动脉和肾脏总RNA，利用含10 000个基因大鼠表达谱芯片检测2组2、3级肠系膜动脉和肾脏组织基因表达水平不同的基因，并用定量 RT- PCR的方法排除假阳性候选基因。结果: 芯片发现19个基因在SHR中上调，其中涉及分子伴侣、离子通道和小分子转运、生长因子、细胞信号转导的蛋白和核转录因子、脂蛋白等基因。用定量 RT- PCR验证示Slc7a8基因的表达水平在SHR组中比WKY组上调9.3倍。结论: Slc7a8可能与高血压的形成有关，深入研究Slc7a8基因及其功能将为进一步了解高血压病的分子机制提供新的思路和线索。     

新的高血压相关基因- Slc7a8的实验研究

目的:探讨高血压致病相关基因。方法:提取13周龄SHR和WKY的2、3级肠系膜动脉和肾脏总RNA,利用含10000个基因大鼠表达谱芯片检测2组2、3级肠系膜动脉和肾脏组织基因表达水平不同的基因,并用定量RT-PCR的方法排除假阳性候选基因。结果:芯片发现19个基因在SHR中上调,其中涉及分子伴侣、离子通道和小分子转运、生长因子、细胞信号转导的蛋白和核转录因子、脂蛋白等基因。用定量RT-PCR验证示Slc7a8基因的表达水平在SHR组中比WKY组上调9.3倍。结论:Slc7a8可能与高血压的形成有关,深入研究Slc7a8基因及其功能将为进一步了解高血压病的分子机制提供新的思路和线索。     

RNA阵列技术检测自发性高血压大鼠肌浆网Ca2+-ATP酶和受磷蛋白基因表达

目的:探讨肌浆网Ca²⁺-ATP酶(SERCA)和受磷蛋白(PLB)在原发性高血压发病过程中的变化特点及其相互关系。方法:提取2、4、6、8、10、12不同周龄雄性自发性高血压大鼠(SHR)和正常血压大鼠(WKY)的心室肌、血管平滑肌、肝脏和肾脏组织的总RNA,共294个样品,利用高通量RNA阵列技术(RNAarray)检测SERCA和PLB基因在不同周龄SHR和WKY中mRNA表达谱改变。结果:SHR在6、8、10、12周龄血压出现显著高于同周龄WKY(均P<0.01),10、12周龄心室肌重量／体重比出现显著增加(均P<0.01),心肌和血管平滑肌SERCA的表达在4、6、8、10、12周龄出现显著高于同周龄WKY(P<0.05或P<0.01)。PLB基因表达在两组间无显著差异(P>0.05)。心肌的SERCA与PLB表达量比值在6、8、10、12周龄出现显著大于同周龄WKY(P<0.05或P<0.01),而血管平滑肌的SERCA与PLB表达量比值在4、6、8、10、12周龄出现显著大于同周龄WKY(P<0.05或P<0.01)。结论:肌浆网SERCAmRNA表达改变及SERCA与PLB比例失常是高血压发生和发展过程中重要的分子生物学机制。     

血管紧张素转换酶2在自发性高血压大鼠肾脏表达与血压的关系研究

目的： 研究血管紧张素转换酶2(ACE2)在20周龄自发性高血压大鼠(SHR)和Wistar Kyoto大鼠(WKY)肾脏组织的表达以及与血压的关系。 方法： 采用实时定量PCR方法检测肾脏组织中ACE2 mRNA的含量，应用放免法测定肾脏组织血管紧张素Ⅱ(AngⅡ)的浓度。 结果： 20周龄SHR的血压明显高于WKY（P<0.05）,SHR肾脏组织ACE2的表达显著低于WKY（P<0.01），而SHR肾脏组织AngⅡ的浓度显著高于WKY（P<0.05）。 结论： ACE2在肾素-血管紧张素系统(RAS)中可能通过改变SHR肾脏中AngⅡ水平调节血压。     

SHR鼠颈上交感神经节内NPY的差异表达研究

目的　通过对自发性高血压大鼠（SHR）颈上神经节形态学及其内神经肽酪氨酸（NPY）表达变化的研究，探讨NPY在高血压发生发展中的作用。 方法　随机选取成年SHR和WKY各20只，观测颈上交感神经节的位置、形状、大小及重量，采用Real-time PCR技术和免疫组织化学法，检测两组大鼠颈上神经节内NPY mRNA和蛋白的表达。 结果　与同周龄的WKY组大鼠相比较，SHR组大鼠血压明显升高（P<0.05）；Real-time PCR和免疫组化结果显示：SHR颈上神经节内NPY mRNA和蛋白水平均较WKY增加（P<0.05）。 结论　NPY在基因转录和蛋白表达等方面均较WKY上调，并参与高血压的形成。     

ICOS信号介导的免疫反应在SHR大鼠肾纤维化中作用的实验研究

目的:初步探讨可诱导共刺激分子(Inducible costimulation molecule,ICOS)介导的免疫反应在原发性高血压肾损害中的作用。方法:采用无创尾动脉血压测量仪动态监测自发性高血压大鼠(Spontaneously hypertensive rats,SHR)及其野生对照组京都维斯塔尔大鼠(Wistar-Kyoto rats,WKY)的血压情况。应用ELISA法动态检测上述大鼠的24小时尿蛋白情况。采用免疫组化技术及RT-PCR法动态检测上述大鼠肾脏中ICOS蛋白及其mRNA的表达水平。应用免疫组化技术及ELISA法动态检测大鼠肾脏及血浆中IL-17A和TGF-β1的表达水平。采用HE及MASSON染色检测各期大鼠肾脏病理改变情况。结果:SHR大鼠从第6周开始血压及24小时尿蛋白值显著高于同期WKY大鼠。SHR大鼠肾脏中ICOS蛋白及其mRNA表达水平从第6周开始亦显著高于同期WKY大鼠,且其表达水平的动态变化均与SHR大鼠肾脏纤维化评分动态变化呈显著正相关关系(r A=0.813,PA0.05;r B=0.753,PB0.05)。SHR大鼠血浆和肾脏中IL-17A、TGF-β1的表达在10周、23周亦显著高于同期WKY大鼠。HE和MASSON染色结果显示,与WKY大鼠相比,SHR大鼠肾脏纤维化程度明显升高,在23周后两者差异具有显著性(P0.05)。结论:在高血压导致的肾损害中,ICOS介导的免疫反应可能起重要的作用。     

不同年龄高血压大鼠血管平滑肌中ERK和MKP-1的表达

目的：研究不同年龄的自发性高血压大鼠（SHR）和Wistar Kyoto大鼠（WKY）主动脉平滑肌中丝裂原活化蛋白激酶（MAPK）及其磷酸酶（MKP-1）的表达及其与高血压的关系。 方法： 用tail-cuff测量大鼠尾动脉血压；分别用Western blotting法和RT-PCR法半定量测定血管平滑肌中磷酸化细胞外信号调节激酶（p-ERK）和MKP-1的蛋白表达以及MKP-1 mRNA的含量。 结果： （1）SHR的血压自8周龄起明显高于WKY（P<0.01），且随年龄增长而升高（P<0.05）至14周以后趋于稳定；（2）SHR主动脉平滑肌中的p-ERK表达明显高于同年龄的WKY（P<0.01），随年龄增长而递增（P<0.05），与血压呈正相关；（3）SHR主动脉平滑肌中MKP-1蛋白明显高于同龄WKY，而mRNA的表达在5周龄时明显高于WKY，之后均随年龄的增长而递减（P<0.05），与血压和ERK呈负相关，而WKY下降不明显。 结论： MKP-1在高血压的发生和发展过程中起重要作用，其表达逐渐下降可能是导致ERK激活增加，从而导致血管平滑肌细胞增殖、血压升高的重要原因。     

阿托伐他汀对自发性高血压大鼠心肌组织PPARs表达的影响

目的： 探讨阿托伐他汀对自发性高血压大鼠心肌组织PPARs（peroxisome proliferator-activated receptors, PPARs）表达的影响及其对心肌肥厚的逆转作用与可能机制。方法: 自发性高血压大鼠分为阿托伐他汀灌胃治疗组（SHR-A，30 mg·kg-1·d-1）及模型组（SHR），治疗8周，同周龄Wistar-Kyoto 鼠为正常血压对照组。治疗前及治疗后2、4、8周测量大鼠尾动脉血压。治疗后测血浆血脂水平，以心脏组织病理分析判断心肌肥厚，Western blotting 检测心肌组织PPARα、PPARγ的表达水平。结果: 经过8周治疗， SHR-A组及SHR组血压及血脂水平无明显差异（P＞0.05）。SHR-A组左室重量指数低于SHR组（P＜0.01）。在SHR-A组，PPARα及PPARγ表达高于SHR组（P＜0.01）。结论: 阿托伐他汀显著改善自发性高血压大鼠心肌组织PPARs表达，有效逆转左室肥厚，可能与其降压及降脂作用无关。     

阿托伐他汀对自发性高血压大鼠HMG-CoA还原酶表达的影响

 目的：评价阿托伐他汀对自发性高血压大鼠（SHR）HMG-CoA还原酶表达的影响。 方法：12只8周龄的SHR随机分为蒸馏水饲养组（SHR_DW组，n＝6）与阿托伐他汀治疗组（SHR_ATV组，n＝6），并以6只同周龄的正常血压大鼠（WKY）作为对照（WKY组，n＝6）。采用RT-PCR与Western blotting法分别检测HMG-CoA还原酶的mRNA及蛋白表达。同时检测血压与血脂。 结果：给药10周后，SHR_ATV组收缩压显著低于治疗前及SHR_DW组（P<0.05），其血清TC、TG、LDL-C及HDL-C的水平与SHR_DW组及WKY组相比，也明显降低（P<0.05）；SHR_ATV组HMG-CoA还原酶mRNA的表达水平在给药10周后显著低于WKY组及SHR_DW组（P<0.05），其蛋白表达水平同样出现类似的结果。 结论：阿托伐他汀能够下调HMG-CoA还原酶的mRNA及蛋白表达水平，不仅使SHR的血脂降低，在某种程度上，还可能与其血压的下降有关。     

Reduced expression of FXYD domain containing ion transport regulator 5 in association with hypertension

Experimental evidence indicates that hypertension is a multifactorial disorder and that the products of several genes may contribute to its development. The aim of this study was to investigate the expression of hypertension-related genes in spontaneous hypertensive rats (SHRs). A microarray screening for hypertension-related genes was conducted in SHRs and Wistar-Kyoto (WKY) rats using total-RNA extracted from second-order mesenteric arteries and kidneys. The FXYD5 mRNA expression in vascular smooth muscle cells (VSMCs) was silenced by RNA interference (RNAi). Meanwhile, the FXYD5 mRNA overexpression in renal tubular epithelial cells (RTECs) was induced by the recombinant plasmid pcDNA3.1(+)-FXYD5. The expression of FXYD5 mRNA was found to be 14.8-fold lower in SHR rats compared to that in WKY rats (P<0.01). The levels of FXYD5 mRNA expression were the highest in kidneys of SHR 13-week-old rats when the blood pressure reached the highest levels. The down-regulated FXYD5 mRNA expression inhibited the migration of smooth muscle cells (P<0.01) and cell membrane Na?-K?-ATPase activity (P<0.01). Up-regulated FXYD5 mRNA expression enhanced the renal tubular epithelial cell membrane Na?-K?-ATPase activity (P<0.05) and cell proliferation (P<0.05). FXYD5 is related to the migration of smooth muscle cells and cell membrane Na?-K?-ATPase activity in rodents. The results of the present study suggest that FXYD5 may have profound impact on the regulation of blood pressure, and that this gene may be a potential target for anti-hypertensive therapy.     

阿托伐他汀对自发性高血压大鼠细胞色素P450羟化酶基因表达的影响

目的： 评价阿托伐他汀对自发性高血压大鼠（SHR）血压和细胞色素P450羟化酶(CYP)4A1的调节作用。方法： 18只SHR随机分为3组：SHR对照组、阿托伐他汀50 mg组(HATV组)和10 mg组(LATV组)；6只Wistar-Kyoto大鼠(WKY)作为正常对照组。给药共10周,分别于给药前和给药后每2周测量大鼠尾动脉收缩压(SBP)；RT-PCR、Western blotting法检测心、肝、肾及主动脉中CYP4A1 mRNA和蛋白质表达；并测定血脂含量。结果： 用药前SHR各组SBP均显著高于WKY组(P<0.01)；HATV组在给药后第6、8、10周和LATV组在给药后第10周SBP明显低于SHR对照组(P<0.05或P<0.01)。在CYP4A1 mRNA及其蛋白质表达中，SHR对照组4种组织均明显高于WKY组(P<0.01或P<0.05)；给药10周后，HATV组心、肾及主动脉和LATV组肾和主动脉的表达均明显低于SHR对照组(P<0.01或P<0.05)；同时，用药2组血脂水平亦明显低于SHR对照组(P<0.01或 P<0.05)。结论： 阿托伐他汀可下调CYP4A1基因的表达，这可能是其降低血压的作用机制之一。     

自发性高血压大鼠多器官微血管稀少动态观察

本研究旨在对自发性高血压大鼠多器管微血管稀少作动态观察。研究对象为自发性高血压大鼠组:5周龄、8周龄、13周龄。WKY组:5周龄、8周龄,13周龄。观察参数为小动脉A_2、A_3、A_4。研究结果显示:(1)自发性高血压鼠视网膜A_2、A_3、A_4进行性减少。(2)自发性高血压鼠心、肾、肌肉小动脉面积密度进行性减少。提示自发性高血压大鼠存在多器管微血管稀少。     

Temporal characteristics of cardiomyocyte hypertrophy in the spontaneously hypertensive rat.

BACKGROUND: The spontaneously hypertensive rat (SHR) is frequently used as model of cardiovascular disease, with considerable disparity in reported parameters of hypertrophy. The aim of this study was to assess the temporal changes occurring during the development and progression of cardiomyocyte hypertrophy in SHR, subsequent to pressure overload, compared to changes associated with normal aging using the normotensive Wistar-Kyoto (WKY) rat. METHODS: Ventricular cardiomyocytes were isolated from rats at 8, 12, 16, 20 and 24 weeks, and parameters of hypertrophy (cell dimensions, protein mass, de novo protein synthesis, and gene expression) and function (contraction and hypertrophic responsiveness in vitro) were assessed. RESULTS: Hypertension was evident at > or =7 weeks in SHRs. Heart:body mass ratio, cardiomyocyte protein mass and width were elevated (P<.05) in SHRs at 16-20 weeks compared to WKYs. In SHRs compared to WKYs at 16 weeks, there was a transient increase (P<.05) in protein synthesis, enhanced hypertrophic responsiveness to phorbol-12-myristate-13-acetate, and induced hypertrophic responsiveness to isoprenaline. Skeletal-alpha-actin mRNA was detected in SHR but not WKY cells at all ages. ANP mRNA was lower in SHR than in WKY cells at 8-20, but progressively increased (P<.05) from 12 to 24 weeks within SHRs. Contractile function increased (P<.05) at 20 weeks in SHR compared to WKY rats. CONCLUSION: Structural and functional changes occurring at the cellular level in the myocardium of SHR follow a distinct pattern, such that pressure overload was initially accompanied by expressional changes (8-12 weeks), followed by active hypertrophic growth and enhanced function (16-20 weeks), which subsequently decelerated as stable compensation was attained.     

Age-related changes in the renal dopaminergic system and expression of renal amino acid transporters in WKY and SHR rats

This study examined age-related changes in renal dopaminergic activity and expression of amino acid transporters potentially involved in renal tubular uptake of l-DOPA in Wistar Kyoto (WKY) and spontaneously hypertensive rats. Aging (from 13 to 91 weeks) was accompanied by increases in systolic blood pressure (SBP) in both WKY and SHR. The sum of urinary dopamine and DOPAC and the urinary dopamine/l-DOPA ratio were increased in aged SHR but not in aged WKY. The urinary dopamine/renal delivery of l-DOPA ratio was increased in both rat strains with aging. LAT2 abundance was increased in aged WKY and SHR. The expression of 4F2hc was markedly elevated in aged SHR but not in aged WKY. ASCT2 was upregulated in both aged WKY and SHR. Plasma aldosterone levels and urinary noradrenaline levels were increased in aged WKY and SHR though levels of both entities were more elevated in aged SHR. Activation of the renal dopaminergic system is more pronounced in aged SHR than in aged WKY and is associated with an upregulation of renal cortical ASCT2 in WKY and of LAT2/4F2hc and ASCT2 in SHR. This activation may be the consequence of a counter-regulatory mechanism for stimuli leading to sodium reabsorption.     

Proximal-tubule-like epithelium in Bowman's capsule in spontaneously hypertensive rats. Changes with age.

Kidneys were samples from male spontaneously hypertensive rats (SHR) and normotensive rats (WKY) in four groups. Renal tissues were examined in 64 rats: 6 SHR and 6 WKY rats 8 and 16 weeks of age and 10 SHR and 10 WKY rats 32 and 64 weeks of age. Tissue samples were fixed, processed, and stained by routine histologic procedures. The parietal layer of Bowman''s capsule in 100-115 renal corpuscles from right to left kidney sections was classified as squamous or cuboidal epithelium. The cuboidal epithelium was similar in structure to that of the proximal tubule. Quantitative information from right and left kidneys was pooled, because the data did not differ significantly. The percentages of renal corpuscles with proximal tubule-like epithelium present at the parietal layer of Bowman''s capsule in the SHR was 13%, 35%, 44%, and 81% at 8, 16, 32, and 64 weeks, respectively. In WKY rats the values were 4%, 0.5%, 5%, and 13% at 8, 16, 32, and 64 weeks, respectively. The increase in the percentage of renal corpuscles with proximal tubule-like epithelium in SHR Bowman''s capsules suggest an association between this tissue and hypertension. The modified layer of Bowman''s capsule may be a response to an increase in blood pressure, may have some role in the etiology of hypertension, or may be irrelevant to hypertension.     

血管内皮生长因子及其基因在自发性高血压大鼠心肌中的表达

目的：血管内皮生长因子（ＶＥＧＦ）是新近确定的一种特异作用于血管内皮细胞的活性肽。最近发现正常心肌细胞有ＶＥＧＦ及其基因表达,但对高血压肥大心脏心肌ＶＥＧＦ及其基因表达的变化尚不清楚。方法：本实验采用免疫组化和分子杂交方法,对自发性设备夸大鼠（ＳＨＲ）肥大于心脏心肌ＶＥＧＦ及其基因表达进行研究。结果：免疫组化结果表明：ＳＨＲ心肌细胞浆内特异性ＶＥＧＦ染色颗粒明显多于ＷＫＹ对照大鼠。Ｎｏｔｈｅｒｎ分