桑杞清眩颗粒干预自发性高血压大鼠心肌细胞凋亡的实验研究

目的观察桑杞清眩颗粒对高血压心肌重构的抑制作用及其可能机制。方法选8只4周龄雄性WKY大鼠和16只4周龄雄性自发性高血压(SHR)大鼠,WKY大鼠作为对照组(WKY),SHR大鼠随机分为模型组(SHR组)和给药组(SQ+SHR组),每组8只。每组在治疗16周后处死大鼠,尾套法测量SHR尾动脉收缩压、舒张压、平均压,计算心脏重量指数;用脱氧核苷酸末端转移酶介导的缺口末端标记法(TUNEL)染色来检测凋亡心肌细胞;用蛋白免疫印迹法检测大鼠心肌组织中B淋巴细胞瘤-2(Bcl-2)、Bcl-2相关X蛋白(Bax)、活化型半胱天冬酶-3(cleaved Caspase-3)。结果与WKY组相比,桑杞清眩颗粒显著抑制SHR大鼠收缩压的升高、心脏重量指数的增加、抑制高血压引起的大鼠心肌细胞凋亡、Bcl-2的降低及Bax和cleaved Caspase-3的增加。结论桑杞清眩颗粒可以抑制SHR大鼠血压升高,减轻心肌肥厚,其作用机制可能与抑制自发性高血压大鼠心肌细胞凋亡有关。     

罗格列酮对自发性高血压大鼠心脏保护作用的形态学研究

目的　探讨自发性高血压大鼠 (SHR大鼠 )心脏形态学的改变及罗格列酮对SHR大鼠心脏的保护作用。方法　SHR大鼠 2 4只 ,随机分成两组。实验期 8w ,取组织标本 ,采用光镜和电镜观察大鼠心肌结构的改变。结果　SHR大鼠心肌间质出现胶原纤维的增殖 ,心肌细胞的结构也发生了改变 ,经罗格列酮治疗后 ,大鼠心肌间质胶原含量明显减少 ,心肌细胞形态得到明显改善。结论　罗格列酮对逆转高血压所致的心肌重构具有一定的作用     

有氧运动对自发性高血压大鼠心脏炎症的影响及机制的探讨

目的 探讨有氧运动对自发性高血压大鼠（SHR）心脏炎症的调节及其机制。方法 8周龄雄性SHR大鼠和正常血压对照WKY大鼠各16只,将SHR大鼠随机分为SHR安静组和SHR运动组;将WKY大鼠随机分为WKY安静组和WKY运动组,每组8只。其中运动组大鼠进行8周无负重游泳运动。采用超声心动仪检测心脏功能,用ELISA试剂盒检测心脏炎症因子TNF-α和IL-1β的含量,Western blot法检测心脏叉头框蛋白1（FoxO1）、p65 NF-κB、磷酸化Akt（p-Akt）和总Akt（t-Akt）的表达。结果 与WKY安静组大鼠相比,SHR安静组大鼠左心室p65 NF-κB的表达以及炎症因子TNF-α、IL-1β的含量及FoxO1表达明显升高（P<0.05,P<0.01）,p-Akt的水平下降（P<0.05）;与SHR安静组相比,8周有氧运动能够增强SHR大鼠心脏功能,降低p65 NF-κB的表达以及炎症因子TNF-α和IL-1β的含量（P<0.05）,同时降低FoxO1表达（P<0.05）,提高p-Akt的水平（P<0.05）。8周有氧运动同样能够降低WKY大鼠心脏FoxO1表达（P<0.05）,提高p-Akt的水平（P<0.05）。结论 8周无负重游泳运动能够降低SHR大鼠心脏炎症因子TNF-α和IL-1β的含量,其可能与加强Akt磷酸化水平和下调FoxO1表达有关,确切机制有待进一步研究。     

依那普利对高血压心肌细胞凋亡影响的实验研究

目的　探讨依那普利对自发性高血压大鼠心肌细胞凋亡的影响。方法　选用 1 2周龄自发性高血压大鼠 (SHR) 4 0只 ,雌雄不拘 ;随机分为治疗组 (2 0只 )和对照组 (2 0只 ) ,并以正常血压大鼠 (WKY)作为对照。治疗组大鼠服用依那普利 (30mg/kg·d- 1 ) 1 2w。每周测体重 1次 ,每 2w测血压 1次 ;治疗结束时测左心室重量 ,并以Tunel方法对三组大鼠心脏作凋亡细胞检测。结果　依那普利治疗后2个月SHR治疗组血压明显低于SHR对照组血压 (P <0 0 1 ) ,与WKY组血压相近似 (P >0 0 5) ;SHR治疗组左心室重量亦明显低于SHR对照组 (P <0 0 1 ) ,略高于WKY组 ,但无统计学差异 (P >0 0 5)。Tunel检查结果表明 ,依那普利治疗组SHR左心室心肌细胞凋亡指数(1 9 5± 3 0 )明显高于SHR对照组 (1 2 6± 1 2 )和WKY组 (7 9± 1 9) ;三组间差异显著 (P <0 0 5)。结论　自发性高血压大鼠心肌细胞凋亡明显高于正常对照WKY ;长期服用依那普利能促进SHR心肌细胞的凋亡。     

自发性高血压大鼠脑出血后炎症反应与Th17细胞的相关性

目的探讨自发性高血压大鼠(SHR)脑出血后炎症反应与Th17细胞的相关性。方法 SHR随机分为正常对照组,假手术组和模型组各5只。胶原酶大脑尾状核注射制备大鼠自发性高血压脑出血(HICH)模型。出血后48 h,冰上取脑。流式细胞仪检测脑组织中Th17细胞占CD4+T细胞的百分比;酶联免疫吸附(ELISA)方法检测脑组织上清中白细胞介素(IL)-6和肿瘤坏死因子(TNF)-α水平。结果与正常对照组和假手术组相比,模型组脑组织中Th17细胞数量明显增加,同时IL-6和TNF-α分泌水平明显升高。结论脑出血急性期炎症反应的诱导和发生与Th17细胞的参与密切相关,Th17细胞促进了脑出血后的病理进程;可能部分通过诱导炎性细胞因子IL-6和TNF-α分泌增加实现的。     

自发性高血压大鼠心脏重构与ACE2 mRNA的表达

目的:观察不同月龄的自发性高血压大鼠(SHR)的心脏血管紧张素转换酶2(ACE2)mRNA表达水平,探讨心脏重构与ACE2的内在联系。方法:将12周龄雄性SHR 18只和12周龄WKY Wistar-Kyoto rats大鼠18只随机分为两组,从WKY大鼠组和SHR组中各抽取9只处死,剩余的9只再喂养12周后处死。测量大鼠心脏的质量(HW)与体质量(BW)并计算HW/BW的比值。以实时定量RT-PCR法检测ACE2 mRNA的表达。结果:①与同周龄WKY大鼠组比较,SHR组HW/BW的比值显著增加(P0.01);与12周龄SHR组比较,24周龄SHR组的HW/BW显著增加(P0.05)。②与同周龄的WKY大鼠组比较,SHR组ACE2 mRNA的表达显著降低(P0.01);与12周龄的SHR组比较,24周龄的SHR组ACE2 mRNA的表达显著降低(P0.01)。结论:自发性高血压大鼠心脏重构伴随着心脏中ACE2 mRNA的表达下调。     

自发性高血压大鼠肾髓质间质细胞内脂性分泌颗粒的研究

选用自发性高血压大鼠（SHR）和对照（WKY）大鼠各9只，雄性．4月龄．血压分别为211.68±6.63mmHg和126.46±2.21mmHg，取肾髓质划分为4个区，分别作光学及电境观察。组织经Levl液固定后，肾髓质间质细胞（RIC）胸浆内脂性颗粒呈黑色；图像分析结果证实SHR大鼠肾髓质各区所含脂性颗粒均较WKY者为少且细小，特别是1区2区内最为显著，本实验提示SHR大鼠RIC内脂性颗粒较少，可能显其高血压发生发展的因素之一。     

氯沙坦或卡托普利对自发性高血压大鼠心脏纤维化的干预研究

目的探讨在不同水平阻断肾素-血管紧张素系统(RAS)对高血压心肌纤维化的影响.方法 29只自发性高血压大鼠(SHR)随机分成(1) SHR对照组(n=15);(2)氯沙坦组(n=7,30 mg*kg-1*d-1);(3)卡托普利组(n=7,100 mg*kg-1*d-1);(4)WKY(n=12)为非高血压组.治疗组每日灌胃给药,对照组蒸馏水灌胃15周后,获取标本.结果 1.SHR心肌血管紧张素Ⅱ(Ang Ⅱ)和醛固酮(Ald)浓度、羟脯氨酸和Ⅰ/Ⅲ型胶原比值较同龄WKY大鼠明显增高(P<0.01),而心肌胶原单体/二聚体(α/β)比值和基质金属蛋白酶-1(MMPs-1)活力降低(P<0.01),且随病程而进一步升高或降低.2.经氯沙坦或卡托普利干预后,心肌Ang Ⅱ、Ald浓度、心肌羟脯氨酸和Ⅰ、Ⅲ型胶原比值有不同程度的降低(P<0.01),而心肌胶原单体/二聚体(α/β)比值和MMPs-1活性升高(P<0.01),逆转了心肌纤维化.3. 氯沙坦在改善胶原表型、胶原可溶性及提高MMPs-1活性优于卡托普利.结论不同水平阻断肾素血管紧张素系统对纤维化逆转不仅减少胶原含量,还改善表型和交联的异常.     

夏膝颗粒对自发性高血压大鼠心肌TGF-β1表达的影响

目的 探讨夏膝颗粒对自发性高血压大鼠(SHR)心肌转化生长因子(TGF-β1)表达的影响及意义.方法 50只12周龄雄性SHR随机分为5组:SHR空白组、阳性药组、夏膝颗粒高、中、低剂量组各10只,分别予以缬沙坦和不同剂量的夏膝颗粒灌胃;同时选取8只同周龄的雄性Wistar-Kyoto大鼠(WKY)作为对照.给药8 w后采用RT-PCR法检测心肌TGF-β1 mRNA水平. 结果与WKY对照组比较,SHR空白组心肌TGF-β1/β-actin吸光值之比显著升高(P<0.01);与SHR空白组比较,夏膝颗粒高剂量组能显著降低SHR TGF-β1 mRNA的表达(P<0.01),甚至低于WKY组(P<0.05).结论 夏膝颗粒可能通过下调心肌TGF-β1的高表达,抑制心肌细胞外基质的增生,防止心室重构.     

盐酸埃他卡林对自发性高血压大鼠血浆生化指标及炎症相关因子的影响

目的观察盐酸埃他卡林(Ipt)对自发性高血压大鼠血浆生化指标及炎症相关因子的影响。方法SHR大鼠在2月龄进入实验,体重200～250g,雌雄不限,随机分为6组:SHR对照组5只,WKY对照组5只,Ipt 3个剂量1、3、9mg·kg~(-1)·d~(-1)治疗组各6只,苯那普利(Ben)6mg·kg~(-1)·d~(-1)治疗组6只。灌胃给药每天1次,8wk后处死动物,检测血浆Glu,Tcho,TG,LDL-c,HDL-c, BUN,Cr,UA,Ins,hs-CRP,IL-6,TNF-α等指标。结果SHR大鼠对照组较WKY大鼠对照组,血浆BUN,Cr,UA显著增高(P＜0．05),血糖、血脂无显著差异(P＞0．05),经Ipt 1、3、9mg·kg~(-1)·d~(-1)及Ben 6mg·kg~(-1)·d~(-1)治疗后,血浆BUN,Cr,UA降至正常;SHR大鼠与WKY大鼠对照组比较,血浆Ins、hs-CRP、TNF-α、IL-6显著增高,Ipt 3、9mg·kg~(-1)·d~(-1)剂量治疗后,较SHR对照组大鼠均显著降低(P＜0．05),1mg·kg~(-1)·d~(-1)剂量及Ben治疗后,无明显改变(P＞0．05)。结论盐酸埃他卡林及苯那普利均能有效地改善肾功能,盐酸埃他卡林3、9mg·kg~(-1)·d~(-1)剂量治疗后能降低血浆Ins、TNF-α、IL-6、hs-CRP等炎症相关因子。     

软脉灵对自发性高血压大鼠心肌纤维化的作用

目的 观察软脉灵对自发性高血压大鼠(SHR)心肌纤维化的影响.方法 选择12周龄雄性SHR 36只,随机分为4组,软脉灵大剂量和小剂量组、空白组、阳性对照组.血压正常的京都Wistar大鼠(WKY)为正常对照组(WKY组).治疗前及治疗12周后用尾袖法测定动脉血压,称重后处死,取心脏,计算左心室重量与体重比(LVM/BW),天狼星红染色,计算心肌胶原容积分数.结果 软脉灵大剂量、小剂量组治疗12周后,收缩压(SBP)均显著低于空白组(P<0.01).与空白组相比,软脉灵大剂量组对SHR心肌外斜层纤维化有明显抑制作用(P<0.01),而软脉灵小剂量组则无影响;与空白组相比,软脉灵大剂量和小剂量组对SHR心肌中环层纤维化及心肌血管周围纤维化均有明显抑制作用(P<0.01).结论 软脉灵可以抑制SHR血压的发展,抑制SHR的心肌纤维化.     

Effect of Decreased Dopamine Synthesis on the Development of Hypertension Induced by Salt Loading in Spontaneously Hypertensive Rats

To clarify role of dopamine in the development of hypertension, the effect of a dopamine synthesis inhibitor on blood pressure and urinary output of catecholamines was investigated in spontaneously hypertensive rats (SHR) fed with high sodium diet. Rats were orally given carbidopa, an inhibitor of peripheral DOPA decarboxylase, or the vehicle for 4 weeks. Carbidopa administration accelerated significantly the development of hypertension as compared to the control SHRs with the vehicle. Carbidopa administration resulted in a significant decrease of urinary excreted sodium, urinary dopamine and renal content of dopamine. Conversely, carbidopa administration resulted in a significant increase of urinary excreted norepinephrine, urinary epinephrine and renal content of norepinephrine as compared with control SHRs. These results suggest that decreased dopamine synthesis in kidneys and probably other peripheral tissue accelerates the development of hypertension, mediated by a decrease of natriuresis and an enhancement of sympatho-adrenomedullary activity. Dopamine plays an important role in its protective action against the development of hypertension enhanced by salt loading, and decreased dopaminergic mechanisms accelerated hypertension in SHR.     

Effects of Chronic Arachidonate on Blood Pressure of Spontaneously Hypertensive Rats

Three weeks of treatment with arachidonic acid (250 mg/kg/day, s.c.) produced an antihypertensive effect in 16 week-old spontaneously hypertensive rats (SHR) as compared with vehicle treated rats. Indomethacin (4 mg/kg, s.c. B.I.D.), given concurrently with arachidonate, abolished the antihypertensive effect. Plasma catecholamines were not altered by the arachidonate treatment, but blood pressure increments after spinal cord stimulation or after intravenous administration of norepinephrine and angiotensin II in the pithed rat were diminished. Increments in plasma catecholamines in response to spinal cord stimulation were similar in both groups of pithed rats.

These data demonstrate the antihypertensive effect of arachidonic acid in SHR with established hypertension. This beneficial effect seems to be mediated through cyclooxygenase metabolites, and might be related to reduced responsiveness of peripheral blood vessels to pressor stimuli.     

Comparison of Norepinephrine Release in Hypertensive Rats: I Hypothalamic and Brainstem Tissues

Stimulation induced ³H-norepinephrine release was measured in hypothalamus and brainstem of spontaneously hypertensive (SHR) and normotensive (WKY) rats. Age dependent changes in ³H-norepinephrine release were shown to occur in the anterior and posterior hypothalamus and the A₂ region of the nucleus tractus solitarius (NTS). In an attempt to determine whether these changes in ³H-trasmitter release were causal or merely secondary to the increase in blood pressure, similar release studies were carried out in DOCA-salt and one kidney-one clip hypertensive animals with similar levels of systolic blood pressure. The changes in stimulus-induced ³H-norepinephrine release seen in the SHR were not observed in the other two models of hypertension, suggesting that one: they were not secondary to an increase in systolic blood pressure; and two that the changes observed in the SHR may possibly play a role in the development and/or maintenance of the hypertension.     

Angiotensin Converting Enzyme Activity in Strains of Normo- and Hypertensive Rats

The concentration of angiotensin converting enzyme (ACE) in the lung, kidney and plasma of the following strains of rats were investigated: Sprague Dawley (SD), Wistar Kyoto (WKY), spontaneously hypertensive (SHR), stroke prone SHR (SP-SHR) and low blood pressure SHR (LBP-SHR) i.e. SHR whose blood pressures were below 150 mm Hg. The enzyme concentrations in the lung of the hypertensive rats were significantly higher than those of the normotensive rats but the reverse was true for plasma ACE concentrations. The kidney ACE concentrations in the hypertensive rats were also lower than those of the normotensive rats, but the differences were not significant. There were no significant differences in enzyme concentrations between the normotensive SD and WKY. Similar results were obtained with the three sub-strains of hypertensive rats despite the fact that their mean blood pressure (MBP) varied significantly from each other.     

Comparative Analysis of Renal Protein Expression in Spontaneously Hypertensive Rat

Objective. Molecular mechanisms of nephrosclerosis caused by hypertension are not well known. Understanding changes in renal protein expression in hypertension may provide further information on how hypertension caused renal injury. Methods and Results. In the present study, we showed the protein expression profiles of the kidney in spontaneously hypertensive rats and Wistar-Kyoto rats using two-dimensional gel electrophoresis (2-DE). Differentially expressed protein spots were excised, underwent in-gel tryptic digestion, and were analyzed by MALDI-TOF MS. Eleven spots were identified. Of these identified spots, four spots were newly appeared, five spots up-regulated, and two spots down-regulated. The identified spots were mainly involved in energy metabolism, lipid transferring between membranes, and cell proliferation. Conclusions. The expression of many proteins have changed significantly in the kidney of spontaneously hypertensive rat. NADP⁺-dependent isocitrate dehydrogenase may be a candidate for further investigation of pathophysiological mechanisms of renal injury in hypertension.     

自发性高血压大鼠左室肥厚及心肌纤维化的动态变化

目的 生高血压大鼠（ＳＨＲ）血压增高的初期。增高期和稳定期左室肥厚和心肌纤维化参数的改变,探讨高血压左室肥厚和心肌纤维化的动态演化规律。方法 应用生化测定、病一检查结合计算机分析等方法,检测ＳＨＲ及其照ＷＫＹ在６周、１４周和２４周的收缩压、左室重量及左室重量指数、心肌细胞面积及横径、民胶原只分数（ＣＶＦ）、血管周围胶原面积（ＰＶＣＡ）及心肌组织内羟脯氨酸浓度。结果ＳＨＲ左室重量及左室重量指数、心肌     

Effect of Long-Term Treatment with Diltiazem on Atrial Natriuretic Peptides in Spontaneously Hypertensive Rats

ABSTRACT

The present study was designed to examine the possible effect of long-term treatment with diltiazem on plasma and atrial concentrations of atrial natriuretic peptides (ANP) in spontaneously hypertensive rats (SHR). Diltiazem treatment reduced blood pressure and ventricular weight in SHR. Plasma ANP concentration in untreated SHR was higher than Wistar-Kyoto rats (WKY). Diltiazem treatment decreased plasma ANP concentration in SHR near to the level of WKY; moreover, plasma ANP concentration was correlated with blood pressure and ventricular weight in treated and untreated SHR. Left atrial ANP concentration in untreated SHR was lower than WKY. Diltiazem treatment increased left atrial ANP concentration in SHR, but this effect was not noted in WKY. These results suggest that the ANP release from the left atrium is chronically stimulated in adult SHR, and that the prevention of an increase in plasma ANP by diltiazem treatment may be, in part, attributed to the improvement of cardiac overload induced by reductions in blood pressure and cardiac hypertrophy.     

Hypertensive Diabetic Rats: Different Effects of Streptozotocin Treatment on Blood Pressure in Adult SHR and in Neonatal SHR

The effect of streptozotocin (STZ) treatment on blood pressure in adult spontaneously hypertensive rats (SHR) was compared with that in neonatal SHR. Three-month-old SHR were intravenously given 10, 30 or 50 mg/kg of STZ. When STZ was given in adult SHR, weight loss, overt hyperglycemia and the reduction of blood pressure occurred dose dependently. Two-day-old pups from SHR were subcutaneously injected with 100 mg/kg of STZ. Neonatal STZ treatment did not attenuate the development of hypertension in SHR. Since neonatally STZ-treated SHR develop mild diabetic symptom with hypertension and develop mild diabetic glomerulosclerosis, they are a good model for studying vascular complications or other disorder relating to the synergism between hypertension and diabetes mellitus.     

Tuberoinfundibular Transport of Intrahypothalamic-Administered Dopamine in Normo- and Hypertensive Rats

ABSTRACT

The dopamine transport system in the tuberoinfundibular tract of the spontaneously hypertensive (SHR), Wistar Kyoto (WKY) and Sprague-Dawley (SD) rats was investigated. The results show that the rate of dopamine transport in this tract is strain-specific. SD rats transported twice as much dopamine (in 30 minutes) as WKY and SHR. The dopamine transport system in the SHR, being at par with that of the WKY, remained intact. These findings suggest that hypertension and the alleged reduced central dopaminergic activity in the SHR is not related to the transport of dopamine in the tuberoinfundibular tract.