平肝胶囊对自发性高血压大鼠心肌纤维化的影响

目的 探讨平肝胶囊对自发性高血压大鼠(SHR)心肌细胞外基质(ECM)内胶原蛋白的影响及其意义。方法50只14周龄雄性SHR随机分为5组,每组各10只,分别予以平肝胶囊高剂量、中剂量、低剂量、苯磺酸左旋氨氯地平片和生理盐水灌胃,同时选同周龄的雄性Wista-Kyoto大鼠(WKY)各10只作为对照。给药10周后采用Ma...     

伊贝沙坦对结缔组织生长因子在自发性高血压大鼠心室肌表达的影响

目的:研究结缔组织生长因子(CTGF)在自发性高血压大鼠(SHR)心脏中的表达及其与高血压心室重构和心肌纤维化的关系,并探讨血管紧张素II受体拮抗剂对其表达的影响以及改善高血压心室重构和心肌纤维可能的作用机制。方法:20只12周龄雄性自发性高血压大鼠随机分为SHR组(n=10)和伊贝沙坦组(n=10),伊贝沙坦组每只大鼠予以伊贝沙坦50mg·kg-1·d-1灌胃,给药12周,同时取10只12周龄雄性京都种Wistar(WKY)大鼠作为对照组,用免疫组化的方法对TGF-β1、CTGF在三组大鼠的左室心肌的分布及表达进行半定量分析;用RT-PCR的方法检测TGF-β1、CTGFmRNA在心肌表达水平;用MASSON染色法观察左室心肌胶原形态,图象分析测量胶原容积分数(CVF)和血管周围胶原面积(PVCA)。结果:(1)左室重量指数(LVI)、CVF、PVCA在SHR组大鼠明显高于WKY组大鼠(P<0.01);相比SHR组,伊贝沙坦组则显著降低(P<0.05)。(2)CTGF主要在血管平滑肌和心肌间质中表达,WKY组在心肌间质中呈弱表达。(3)相关分析表明,CTGF与TGF-β1(r=0.562,P<0.05)的表达呈正相关。(4)CTGF及其mRNA在SHR组左室心肌中的表达较WKY组明显增强(P<0.05),相比SHR组,伊贝沙坦组则明显减少。结论:高血压大鼠心室肌CTGF表达增加,伊贝沙坦对高血压大鼠心室肌CGTF表达具有抑制作用,且能够明显改善高血压心室重构和心肌纤维化,此种作用可能是血管紧张素II受体拮抗剂抑制左室重构改善心肌纤维化新的机制。     

自发性高血压大鼠颈动脉中膜基质金属蛋白酶-9和基质金属蛋白酶抑制剂-2的表达及替米沙坦的干预作用

目的:观察自发性高血压大鼠(SHR)颈动脉基质金属蛋白酶-9(MMP-9)和基质金属蛋白酶抑制剂-2(TIMP-2)的表达,并探讨替米沙坦对其的干预作用.方法:30只雄性12周龄的SHR随机分为3组:高血压组(SHR)、替米沙坦低剂量组(TelL)、替米沙坦高剂量组(TelH),并设同周龄雄性的WKY大鼠为对照组(WKY,n=10).干预18周,观察各组大鼠SBP、颈动脉中膜胶原面积百分比.用免疫组化评估MMP-9和,TIMP-2在颈动脉中膜的表达水平.结果:两周后TelH组SBP明显低于SHR组(P<0.01),其降压作用持续至实验结束,而TelL组SBP与SHR组无统计学差异(P>0.05).SHR组中膜胶原面积百分比明显高于WKY组(P<0.01),TelH、TelL组的中膜胶原面积百分比低于SHR组(P<0.05).SHR组中膜MMP-9的吸光度值(IOD)明显低于WKY组(P<0.01).TelH、TelL组中膜MMP-9的IOD值高于SHR组(P<0.05).SHR组中膜TIMP-2的IOD值明显高于WKY组(P<0.01),TelH、TelL组中膜TIMP-2的IOD值低于SHR组(P<0.05).结论:SHR颈动脉中膜MMP-9表达减少,TIMP-2表达增多,替米沙坦能通过降压及上调MMP-9、下调TIMP-2的表达,从而减轻颈动脉的纤维化.     

ELK-1与原发性高血压大鼠左心室重构关系的研究

目的研究ELK-1在原发性高血压大鼠(SHR)左心室的表达情况,探讨ELK-1与高血压左心室重构的关系。方法对比观察各周龄SHR大鼠与WKY大鼠血压,心脏/体质量比值变化;RT-PCR方法检测左心室ELK-1的表达。结果在整个实验过程中,WKY血压保持在正常水平,24周龄SHR组尾动脉收缩压明显高于同周龄WKY组(P<0.05);与同周龄WKY相比24周龄SHR组的心脏/体质量比值增加明显(P<0.05);大鼠左心室肌经RT-PCR检测分析,随周龄增加SHR左心室中ELK-1含量逐渐增高,24周龄的SHR组含量明显高于同周龄WKY组大鼠(P<0.05),且24周龄大鼠的含量明显高于8周龄大鼠的(P<0.05)。结论 ELK-1可能对高血压左心室心肌肥厚发展有促进作用。     

银杏内酯B对自发性高血压大鼠左室肥厚及心肌纤维化的影响

目的:观察银杏内酯B对自发性高血压大鼠模型左室肥厚心肌纤维化的影响。方法:选择12周龄雄性SHR大鼠(二级)40只,随机分成4组,每组10只,分别为银杏内酯B大剂量组(YH,120 mg.kg-1.d-1)、银杏内酯B小剂量组(YL,60mg.kg-1.d-1)、氯沙坦组(LOS,30 mg.kg-1.d-1)和SHR大鼠模型对照组(SHR),以及周龄、性别相匹配的Wistar Kyoto(WKY)大鼠10只作为空白对照。每日灌胃给药一次,对照组给等量CMCNa溶液。治疗12周后尾袖法测定动脉血压,称量后处死。计算左室质量与体质量比(LVM/BW)。天狼星红染色,计算机图像分析计算心肌胶原容积分数。结果:给药后,YH、YL组大鼠SBP均明显低于SHR组(P<0.01),YH、YL2组组间比较无显著性差异;YH组大鼠给药前后SBP比较有显著差异(P<0.01),给药后明显低于给药前,而YL组给药前后比较无统计学意义。YH、YL组大鼠心肌胶原纤维含量均明显低于SHR组(P<0.01),YH、YL2组间比较无显著性差异。结论:银杏内酯B可以抑制SHR大鼠的心肌纤维化,改善高血压所致的心肌重塑。     

黄芪对自发性高血压大鼠心肌受磷蛋白和肌浆网钙泵表达的影响

目的:观察自发性高血压大鼠(spontaneously hypertensive rats,SHR)在高血压早期心肌肌浆网中的钙泵(Ca2 -AT-Pase,SERCA)和受磷蛋白(PLB)在蛋白水平表达量的变化,探讨黄芪注射液对SHR心肌PLB和SERCA表达的影响。方法:将18只自发性高血压大鼠(SHR)与17只Wistar-kyoto大鼠(WKY)随机各分为空白对照组、黄芪低剂量组、黄芪中剂量组、黄芪高剂量组4组,分别每天腹腔注射0.9mL生理盐水和0.9,1.2,1.8mL的黄芪注射液共8周,再测量大鼠心肌中的PLB和SERCA在蛋白水平的表达。结果:SHR空白组心肌PLB和SERCA在蛋白水平的表达,较WKY空白组明显下降(P<0.05);SHR大剂量黄芪组心肌PLB和SERCA在蛋白水平的表达,较SHR空白组明显升高(P<0.05)。结论:大剂量黄芪注射液能显著增加SHR心肌PLB和SERCA在蛋白水平的表达,在高血压早期SHR心肌肌浆网中PLB和SERCA在蛋白水平表达已有明显下降。     

贝那普利联合螺内酯对自发性高血压大鼠左心室重构的影响

目的 探讨小剂量贝那普利联合螺内酯早期应用对自发性高血压大鼠(SHR)左心室重构的影响及其机制.方法 6周龄雄性SHR 14只,随机分为模型对照组(SHR-c组)和药物干预组(盐酸贝那普利5 mg·kg-1·d-1+螺内酯10 mg·kg-1·d-1,SHR-bs组),每组7只.同周龄同性别的WKY大鼠作为正常血压大鼠...     

自发性高血压大鼠(SHR)心肌纤维化和巨噬细胞关系的研究——苯那普利干预试验

目的探讨巨噬细胞在自发性高血压大鼠(SHR)心肌纤维化中的作用以及苯那普利对其影响及其机制。方法12wk♂SHR分为高血压组(SHR,n=10)、苯那普利治疗组(BenL、BenH亚组,分别予苯那普利1.7、17mg.kg-1.d-1灌胃;n=10),另设年龄、性别配对的WKY大鼠为对照(WKY,n=10)。干预18wk后,测量和计算各组大鼠收缩压(SBP)、左室重量(LVM)、左室重量指数(LVMI)、左室心肌胶原含量和巨噬细胞数目;逆转录-聚合酶链反应(RT-PCR)测定各组大鼠心肌转化生长因子-β1(1(TGF-β1)和白介素-6(IL-6)的转录水平。结果SHR组SBP较WKY大鼠升高(P<0.01),BenH组的SBP明显低于SHR组(P<0.01),BenL组SBP无明显变化;SHR组较WKY心肌中巨噬细胞数目明显增多,TGF-β1和IL-6的信使核糖核酸(mR-NA)水平也明显升高(P<0.01);而BenL和BenH组SHR心肌中巨噬细胞数目和TGF-β1及IL-6的mRNA水平均较SHR组降低(P<0.05);大鼠心肌中巨噬细胞数目分别与心肌胶原容积分数(CVF)、心肌内血管周围胶原面积(PVCA)含量呈正相关(P<0.01)。结论巨噬细胞在SHR大鼠心肌纤维化中具有重要作用,苯那普利可减轻SHR心肌纤维化和巨噬细胞浸润,且可下调TGF-β1和IL-6的mRNA表达。     

缬沙坦对自发性高血压大鼠心肌抑癌基因PTEN表达的影响

目的 :观察缬沙坦对自发性高血压大鼠(SHR)心肌肥厚的影响 ,以及对肿瘤抑制基因PTEN表达的影响。方法 :取 2 0只 12周龄自发性高血压大鼠 ,随机分为 2组 ,每组 10只 :缬沙坦干预组 ,给予缬沙坦 30mg·kg-1·d-1溶于饮水灌胃治疗 ;SHR阳性对照组给予正常饮水。另有 10只同龄同源雄性正常血压Wistar kyoto大鼠 (WKY组 )作为正常对照组。实验周期 8周 ,测量血压、左室重量 体重(LVW BW ) ,应用免疫组化方法检测各组大鼠左心室心肌PTEN的表达。结果 :SHR阳性对照组血压、LVW BW均高于正常对照组 ,但低于缬沙坦组 ,SHR阳性对照组PTEN的表达明显低于正常对照组 ,而缬沙坦组PTEN的表达显著高于SHR阳性对照组。结论 :缬沙坦能抑制自发性高血压大鼠心肌肥厚 ,并能提高PTEN的表达 ,提示PTEN可能在心肌肥厚发展过程中起了一定的作用。     

鱼皮胶原多肽的降血压效果研究

目的探讨罗非鱼鱼皮胶原多肽的降压效果。方法采用原发性高血压大鼠(SHR)和京都Wistar大鼠(WKY)作为实验动物,通过一次性给药实验和长期给药实验,分析比较不同剂量的鱼皮胶原多肽和卡托普利(Captopril)对SHR和WKY的血压、血液血管紧张素Ⅱ(AngⅡ)含量、心率及体重的影响。结果在一次性给药实验中各剂量组和Captopril组SHR血压均有显著下降,其中高剂量组收缩压下降幅度最大,下降了30.37mmHg;长期给药实验中,SHR血压下降后保持稳定,且AngⅡ含量降低,高剂量组比对照组低了51.13ng·L-1;鱼皮胶原多肽对京都Wistar大鼠(WKY)的血压值和AngⅡ含量没有...     

ANGIOTENSIN CONVERTING ENZYME INHIBITOR, CAPTOPRIL, INHIBITS CARDIAC HYPERTROPHY WITHOUT CHANGING COLLAGEN TYPES AND CONCENTRATION IN SPONTANEOUSLY HYPERTENSIVE RATS

1. The effects of the ACE inhibitor, captopril, on collagen metabolism in spontaneously hypertensive rats (SHR) with cardiac hypertrophy was examined. Captopril (100 mg/kg per day) was administered in drinking water to 20 week old male SHR for 12 weeks. Collagen concentration was calculated from hydroxyproline content, and relative proportions of types I, III and V collagen were determined by non-interrupted SDS-polyacrylamide gel electrophoresis (SDS-PAGE). These parameters were examined in age and sex matched Wistar-Kyoto (WKY) rats, as well as in non-treated SHR, and compared with those of captopril-treated SHR. 2. Captopril significantly reduced both blood pressure (191 ± 12.1 vs 146 ± 11.2 mmHg, P < 0.01), and the ratio of left ventricular (LV) weight to bodyweight (BW; 2.38 ± 0.17 vs 2.05 ± 0.12 mg/g, P < 0.01). There were no significant differences in collagen concentration among WKY rats, captopril-treated SHR and non-treated 32 week old SHR. However, total collagen content in captopril-treated SHR reduced significantly compared with non-treated 32 week old SHR (16.8 ± 2.0 vs 21.3 ± 0.8 mg, P < 0.01). The relative proportion of type V collagen was significantly higher in both captopril-treated (58.6 ± 3.4 vs 46.8 ± 1.3%, P < 0.01) and non-treated 32 week old SHR (59.9 ± 3.1 vs 46.8 ± 1.3%, P < 0.01) compared with WKY rats. However, there were no significant differences between captopril-treated SHR and non-treated 32 week old SHR. 3. The data from this study showed that captopril reduced cardiac hypertrophy, as reported previously, but did not change collagen types and concentration of the hypertrophied myocardium in SHR.     

罗沙坦对自发性高血压肾小动脉重建的逆转作用

目的　研究血管紧张素Ⅱ受体拮抗剂罗沙坦对高血压肾小动脉重建的逆转作用。方法　 16wk龄 大鼠分为 :正常血压大鼠 (WKY)组、自发性高血压大鼠 (SHR)对照组、罗沙坦治疗高剂量组 (15mg·kg-1·d-1)和罗沙坦治疗低剂量组 (0 75mg·kg-1·d-1)。每组 6只大鼠 ,饲养 10wk。在肾组织切片上用光镜结合计算机图像分析法观测肾内小动脉的几何形态学指标 ,离体肾脏灌流法测定最小肾血管阻力。结果　罗沙坦高剂量组的尾动脉收缩压、肾内小动脉壁厚、壁面积、壁厚内径比和最小肾血管阻力 ,均较高血压对照组显著下降或减小 ;罗沙坦低剂量组的肾内小动脉壁厚和壁厚内径比较高血压对照组显著下降或减小。结论　AngⅡ受体拮抗剂能逆转SHR肾小动脉的重建 ,而且是非血压依赖性的     

Hydralazine reduces leukocyte migration through different mechanisms in spontaneously hypertensive and normotensive rats

In addition to reducing blood pressure, hydralazine can reduce the production of inflammatory cytokines and reduce the expression of leukocyte adhesion molecules. Differences in leukocyte behavior and leukocyte adhesion molecule expression in spontaneously hypertensive rats (SHR) compared to normotensive rats have been reported. However, whether hydralazine can reduce leukocyte migration in vivo in hypertension and in normotension remains unknown. To address this question, male SHR and Wistar rats were treated for 15 days with hydralazine at a dose of ~3.5 mg/kg or ~14 mg/kg in their drinking water. The numbers of rollers and adherent and migrated cells were determined by direct vital microscopy, and blood pressure was assessed by tail plethysmography. In addition, following treatment with the higher dose, immunohistochemistry was used to measure the expression of intercellular adhesion molecule-1 (ICAM-1), P-selectin, and platelet-endothelial cell adhesion molecule-1 (PECAM-1) in endothelial cells, while flow cytometry was used to evaluate the expression of leukocyte CD18 and L-selectin. Hydralazine reduced leukocyte adherence and migration in SHR either at the higher, that reduced blood pressure levels, or lower dose, which did not reduce it. Reduced ICAM-1 expression might be involved in the reduced migration observed in SHR. In Wistar rats, only at the higher dose hydralazine reduced blood pressure levels and leukocyte migration. Reduced P-selectin expression might be involved. We therefore conclude that hydralazine reduces leukocyte migration by different mechanisms in SHR and Wistar rats, specifically by reducing ICAM-1 expression in the former and P-selectin expression in the latter.     

益肾平肝方对SHR血压及RAS系统表达的影响

目的1．观察益肾平肝方对血压的影响;2．观察益肾平肝方对自发性高血压大鼠（SHR）肾素血管紧张素系统（RAS）的影响。方法以同龄雄性SHR和正常血压大鼠（Wistar—Kyotorats,WKY）为研究对象,在10周龄时,SHR随机分为模型组（蒸馏水）、中药组（益肾平肝方）和西药组（洛汀新）,WKY作为正常对照组（蒸馏水）,每组8只,用药12周,检测实验第0、6、12周大鼠血压,实验12周末,检测大鼠血清及肾脏血管紧张素转换酶2（ACE2）和血管紧张素Ⅱ（AngⅡ）含量,所得结果进行统计分析。结果12周时,与模型组比较发现,中药组、西药组大鼠血压明显降低（P〈0．01）,中药组大鼠血清ACE2较WKY对照组及西药组明显减少（P〈0．05）,AngⅡ明显增加（P〈0．05）,与模型组无统计学差异（P〉0．05）,而二者在肾脏中的表达却不同,中药组大鼠肾脏ACE2较模型组明显增加（P〈0．05）,与西药组、WKY对照组无统计学差异（P〉0．05）,AngⅡ则明显减少（P〈0．05）,与WKY组无统计学差异（P〉0．05）。结论益肾平肝方能降低SHR血压从而减轻。肾脏损害,其作用可能与调节肾脏局部RAS的表达有关。     

培哚普利,普萘洛尔与双氢氯噻嗪对自发性高血压大鼠心血管结？…

AIM: To investigate the effects of perindopril, propranolol, and dihydrochlorothiazide on artery wall thickening, left ventricular hypertrophy, and cardiac fibrosis in spontaneously hypertensive rats (SHR). METHODS: After measurement of systolic blood pressure (SBP), 16-wk-old Male SHR were randomly divided into 3 groups (each n = 10), given perindopril (Per, 5 mg.kg-1.d-1), propranolol (Pro, 40 mg.kg-1.d-1), dihydrochlorothiazide (DCT, 100 mg.kg-1.d-1) respectively by gavage for 12 wk. Sex-, age-, and number-matched untreated SHR and normotensive Wistar Kyoto rats (WKY) served as controls. When the treatment finished, body weights (BW) and SBP were measured before decapitation of the rats. The heart was excised rapidly, the left ventricle was weighed and then subjected to collagen content analysis. Vascular wall and lumen ratio from aorta, renal arteries and branch III vessels of mesenteric arteries were determined morphometrically. RESULTS: Treated rats in 3 groups showed a lower SBP and the ratio of left ventricle weight to body weight (LVW/BW) compared with WKY. Artery wall thickening was similarly inhibited in the treated groups. Per and Pro inhibited cardiac fibrosis, but collagen concentration increased in DCT treated SHR [collagen volume fraction (CVF): 19 +/- 4 vs SHR 14 +/- 4, P < 0.05; perivascular collagen fraction(PVCF): 84 +/- 7 vs SHR 79 +/- 5, P < 0.05]. CONCLUSION: Per and Pro inhibited, but DCT promoted, cardiac fibrosis.     

Evidence for a visceral smooth muscle abnormality in Okamoto spontaneous hypertension.

1. In order to discover whether the changes in reactivity are related to the primary cause of hypertension in spontaneously hypertensive rats (SHR) or are just an adaptation induced by the high arterial blood pressure we tested the contractile response of a visceral smooth muscle from such rats. 2. Longitudinal strips of the fundus from 20 week old male and female SHR and Wistar normotensive (NW) rats were used. Dose-response curves to Ba2+ in SHR strips were displaced to the right as compared to NW rats. Maximal responses were identical. Male SHR fundus strips contracted much more with Sr2+ (SHR: 42+/-3% of maximum response to Ba2+, n=10; NW: 19+/-4%, n=10, P less than 0.01) than NW strips. There was no difference in the response to both BaCl2 and SrCl2 between female SHR and NW fundus strips, and MnCl2 and LaCl3 were relaxant in all cases. 3. Dose-response curves to Ca2+ of depolarized SHR and NW fundus strips were obtained and the effect of diazoxide on Ca2+ contractions was observed. The contractile action of Ca2+ in depolarized preparations was enhanced in both male and female SHR strips. The effect of diazoxide was more marked in SHR strips than in NW fundus strips. 4. SHR fundus smooth muscle shows the same modification of reactivity to Ba2+, Sr2+, Ca2+ and diazoxide that was previously described in arterial smooth muscle. This indicates that the cellular modification responsible for the increase of vascular tonus in SHR is not an adaptive reaction to high blood pressure. The differences between female SHR and male SHR responses are not unexpected, considering the natural evolution of hypertension in Okamoto rats which is milder in the female.     

Down-regulation of the GABA-ergic system in selected brain areas of spontaneously hypertensive rats (SHR)

The relevance of GABA-ergic system in hypertensive state has been studied. GABA content, GAD activity and GABA-A receptor binding in various brain areas in age-matched spontaneously hypertensive (SHR) and normotensive Wistar-Kyoto rats (WKY) was compared. Out of 9 brain areas studied the GABA content was significantly lower in the substantia nigra, hypothalamus, hypothalamus posterior and hippocampus of SHR rats. GAD activity was lowered in the hypothalamus and hippocampus of young SHR and adult SHR rats (4, 8, 14 weeks old). Scatchard analysis of the binding isotherms indicated a lower Bmax of the binding sites in the hypothalamus and hippocampus of 8 and 14 weeks old SHR rats. These results suggest that activity of GABA-ergic system differs substantially in SHR and WKY rats brain. Furthermore, these differences appear already in young prehypertensive SHR rats as well as in the early stages of hypertension.     

Withdrawal reveals lack of effect of prolonged antihypertensive treatment on intrinsic aortic wall stiffness in senescent spontaneously hypertensive rats

1. Chronic antihypertensive treatment lowers cardiovascular morbidity and mortality. The beneficial effect on the blood vessel wall may be due to the lowering of blood pressure (BP) and, hence, wall stress (WS), or to a treatment-induced change in wall structure. 2. We have previously shown that, when evaluated at the same level of BP and WS, the stiffness of the aortic wall of old spontaneously hypertensive rats (SHR) is higher than that of young and adult SHR and that of age-matched Wistar-Kyoto (WKY) rats. In the present study, we tested the hypothesis that the intrinsic changes in wall composition and mechanics in old SHR can be modulated by long-term treatment with an angiotensin I-converting enzyme inhibitor (captopril; 40 mg/kg per day) combined with a diuretic (hydrochlorothiazide; 20 mg/kg per day) and that treatment withdrawal would reveal whether such changes are maintained when BP and WS return to pretreatment levels. 3. We evaluated aortic structure and mechanics in SHR following 1 week withdrawal of oral antihypertensive treatment from 3 to 15 months of age (n = 8). Results were compared with age-matched SHR that were maintained on treatment (n = 12) or were not treated (n = 13) and with WKY rats (no treatment n = 11; maintained n = 11; withdrawn n = 10). 4. Isobaric aortic wall stiffness was estimated from the ratio of baseline aortic pulse wave velocity (PWV) to BP and the slope relating aortic PWV to BP following sodium nitroprusside-induced hypotension. Relative wall stiffening was estimated as the ratio of elastic modulus (EM) to WS. We argued that if treatment produced a change in wall elastin or collagen content, with a subsequent decrease in isobaric wall stiffness, then this would be maintained when BP increased following withdrawal of treatment. 5. In old SHR, treatment lowered isobaric wall stiffness (baseline PWV/BP 4.6 +/- 0.3 cm/s per mmHg; slope relating PWV to BP 6.7 +/- 0.4 x 10-3 cm/s per mmHg and EM/WS 4.1 +/- 0.4 vs 6.1 +/- 0.4 cm/s per mmHg, 9.7 +/- 0.9 x 10-3 cm/s per mmHg and 8.9 +/- 1.1, respectively, without treatment; all P < 0.05). After 1 weeks treatment withdrawal, the indices (5.7 +/- 0.2 cm/s per mmHg, 9.1 +/- 0.2 x 10-3 cm/s per mmHg and 7.2 +/- 0.6) increased in parallel with the increase in WS to levels similar to those observed in untreated SHR. There were no significant differences among the WKY rat groups. 6. Treatment increased the elastin and collagen contents of the aortic wall in both SHR (196 +/- 13 and 128 +/- 5 vs 111 +/- 9 and 86 +/- 4 mg/g wet weight, respectively, in untreated; P < 0.05) and WKY rats (190 +/- 19 and 135 +/- 4 vs 115 +/- 7 and 114 +/- 5 mg/g wet weight, respectively, in untreated; P < 0.05). This increase remained following withdrawal (213 +/- 26 and 118 +/- 4 vs 161 +/- 14 and 127 +/- 4 mg/g wet weight in SHR and WKY rats, respectively). 7. In summary, 1 year of treatment with captopril plus hydrochlorothiazide increases wall elastin content and reduces WS and stiffness in old SHR. Following withdrawal, elastin content remains high, but wall stiffness parallels WS in a manner similar to that in untreated SHR.     

硫化氢对自发性高血压大鼠胸主动脉舒张反应的影响

目的 探讨内源性及外源性硫化氢(H_2S)对自发性高血压大鼠(SHR)离体胸主动脉舒张反应的影响。方法 4wb WKY大鼠24只,随机分为WKY对照组(n=8)、WKY+H_2S组(n=8)及WKY+PPG组(n=8)。同样周龄SHR大鼠24只,随机分为高血压对照组(n=8)、高血压+H_2S组(n=8)及高血压+PPG组(n=8),高血压对照组及WKY对照组大鼠每日腹腔注射生理盐水,WKY+H_2S组及高血压+H_2S组每日腹腔注射硫氢化钠(NaHS),WKY+PPG组及高血压+PPG组每日腹腔注射PPG,5 wk后处死,取胸主动脉,观察其对乙酰胆碱(ACh)、硝普钠(SNP)及NaHS的舒张反应。结果 WKY+PPG组及高血压对照组、高血压+PPG组对ACh及SNP的舒张率较WKY组降低(P<0.05),而高血压+H_2S组较高血压对照组升高(P<0.05),与WKY对照组相似;各组大鼠血管环对SNP的舒 张反应均高于ACh(P<0.05);WKY对照组及高血压对照组对不同浓度的NaHS呈现剂量依赖性舒张反应,对于同样浓度的NaHS,高血压对照组较WKY对照组的舒张率高。结论 H_2S可以独立及与一氧化氮协同发挥舒张血管效应,在自发性高血压血管舒张功能异常的形成机制中占据重要地位。     

不同剂量valsartan应用对SHR血压和左室心肌肥厚的影响

目的评价不同剂量ATi受体拮抗剂valsartan对SHR的降压疗效及其逆转心肌肥厚作用的影响。方法18只14周龄雄性SHR随机分成空白对照组、小剂量valsartan组、大剂量valsartan组，另设WKY正常对照组，分别给予生理盐水、valsartan8mg