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1.
江时森  李辉 《心肺血管病杂志》1994,13(2):104-105,101
本工作观察了卡托普利对自发性高血压大鼠(SHR)血压及心肌,主动脉组织肾素血管紧张素系统(RAS)的影响,实验结果表明,SHR心肌,主动脉组织血管紧张素Ⅱ含量(ATII)和血管紧张素换酶(ACE)活性显著高于正常血压大鼠(WKY)。卡托普列能显著抑制SHR心肌,主动脉组织ACE活性;降低ATII含量,并使血压明显降低。提示,血管紧张素转换酶抑制剂(ACEI)对心血管局部组织RAS的抑制作用在其降压  相似文献   

2.
本工作观察了卡托普利对自发性高血压大鼠(SHR)血压及心肌、主动脉组织肾素血管紧张素系统(RAS)的影响,实验结果表明,SHR心肌、主动脉组织血管紧张素Ⅱ含量(ATII)和血管紧张素转换酶(ACE)活性显著高于正常血压大鼠(WKY)。卡托普列能显著抑制SHR心肌、主动脉组织ACE活性;降低ATII含量,并使血压明显降低。提示,血管紧张素转换酶抑制剂(ACEI)对心血管局部组织RAS的抑制作用在其降压机制中发挥重作用。  相似文献   

3.
为探讨高血压大鼠(SHR)心肌胶原增生与心肌局部血管紧张素Ⅱ(AngⅡ)、醛固酮(Ald)的关系。方法应用羟脯氨酸法测定大鼠心肌胶原含量,用放免法测定心肌局部AngⅡ、Ald含量,将两者进行线性相关分析。结果自发性高血压大鼠(SHRn=7)与对照组(WKYn=7)相比,心肌胶原含量增加(P<0.01)。相关分析表明,心肌胶原含量与心肌局部AngⅡ含量呈正相关(r=0.72,P<0.05),与心肌局部Ald含量呈显著正相关(r=0.885,P<0.001),而与血压(SBP)无明显相关(r=0.398,P>0.05)。结论SHR心肌胶原含量较正常大鼠增加,并且与心肌局部AngⅡ、Ald含量增加有关。  相似文献   

4.
通过体外培养3周龄自发性高血压大鼠(SHR)胸主动脉血管平滑肌细胞(ASMC),探讨SHR高血压形成前期ASMC是否存在异常增殖,以及与循环、血管局部血管紧张素Ⅱ(AngⅡ)、血管紧张素转换酶(ACE)的关系。结果表明:3周龄SHRASMC肾素-血管紧张素系统(RAS)处于高功能状态,合成AngⅡ、ACE,分泌AngⅡ的量比WKY高(P<0.05),并呈现异常增殖,3H-TdR参入增加,倍增时间(DT)缩短(P<0.01)。血管紧张素转换酶抑制剂(ACEI)卡托普利、AngⅡ受体拮抗剂Saralasin长期干预可通过抑制SHRASMCAngⅡ生成或阻断AngⅡ的作用进而抑制其异常增殖。而WKY血浆AngⅡ、ACE活性反比SHR高(P<0.01)。说明:血管局部RAS处于高功能状态对SHR高血压前期ASMC异常增殖起重要作用,而循环RAS则不起作用。  相似文献   

5.
以心肌氧自由基浓度,超氧化物歧化酶活性、丙二醛含量为指标,观察了增龄对心肌自由基反应的影响,结果表明:(1)心肌OFR浓度随增龄上升,至13、17月龄时达到显著水平(P<0.05);(2)心肌SOD活性随增龄下降,至13、17月龄时达到显著水平(P<0.05);(3)心肌MDA含量随增龄而增加,至13、17月龄时增加显著(P<0.05,O<0.01);(4)老年小鼠(17月龄)心肌SOD活性与OF  相似文献   

6.
目的 研究纤溶酶原激活物抑制物-1(PAI-1)在糖尿病大鼠肾皮质的表达和牛磺酸对它的调节作用。方法 链脲佐菌素诱发的糖尿病大接受牛磺酸治疗14周后,测定肾皮质血管紧张素转换酶(ACE)活性,血管紧张素Ⅱ(AngⅡ)含量、组织型纤溶酶原活的(t-AP)和PAI-1生物活性。用Northern杂交检测肾皮质PAI- MRAN表达。结果 与对照组大鼠相比,糖尿病组大鼠肾皮质ACE、PAI-1活性和An  相似文献   

7.
19例心功能障碍患者的血浆、心肌血管紧张素Ⅱ(AngⅡ)、心钠素(ANF)含量高于正常对照组;血浆AngⅡ和ANF含量增高与心脏指数(CI)呈显著负相关(r=-0.5968,P<0.05;r=-0.8996,P<0.01),心肌AngⅡ含量变化与左室心肌重量(LVM)呈显著正相关(r=0.5723,P<0.05);提示心脏局部肾素-血管紧张素系统(RAS)活性增高和ANF变化参与心肌细胞增殖及心室重塑的意义较为突出。  相似文献   

8.
符民桂  杨军 《高血压杂志》1998,6(4):291-295
探讨NO系统和血管α1-肾上腺素受体α1-AR)及三磷酸肌醇受体(IP3R)系统在高血压发病中的相互作用。方法在常规饲食中加入L-NAME喂饲大鼠1或4周制备大鼠高血压模型;应用放射性配基结合实验观察α1-AR及IP3R的变化。结果应用L-NAME处理一周,大鼠动脉血压升高30(2mmHg(P<0.05),血浆NOx含量则下降25%(P<0.05)。主动脉肌膜α1-AR及肌浆网IP3R密度分别增加12%和40%。L-NAME处理4周,大鼠血压升高75±8mmHg(P<0.01),血浆NOx含量下降50%(P<0.01),主动脉肌膜α1-AR及肌浆网IP3R密度分别较对照组高73%和137%(P<0.01),此时尾动脉肌膜AR及肌浆网IP3R密度亦较对照组增加55%和56%(P<0.01)。结论提示长期抑制NOS引起大鼠持续性高血压的同时,可致大鼠血管α1-AR及IP3R明显上调。  相似文献   

9.
为研究卡托普利(CAP)对心血管组织肾素─血管紧张素系统的影响,5周龄雄性卒中型自发性高血压大鼠(SHRsp)随机分为实验组(n=12)及对照组(n=8),分别于食管内喂饲CAP(60mg·kg-1/d)或蒸馏水,每日1次,持续8周。用放射免疫法测定血浆肾素活性、血管紧张素Ⅱ(AngⅡ),心肌和主动脉平滑肌(ASM)的肾素浓度(RC)和AngⅡ含量。结果显示,实验组血压不升高,心室重/体重比值也低于对照组;心肌和ASM的RC比对照组高;而AngⅡ被明显抑制,分别为7.02±0.96比13.40±5.39(P<0.01)和24.80±4.93比33.65±8.89pg/mg蛋白(P<0.02)。这说明,CAP长期治疗可明显阻止SHRsp的血压上升及心肌肥厚的发生,降低心肌和ASM中AngⅡ含量,提示在这种模型,CAP降压及抗心肌肥厚的重要机制之一是阻断心血管组织局部AngⅡ的生成。  相似文献   

10.
甘草对老年大鼠SOD,LPO,MAO—B影响的实验研究   总被引:4,自引:0,他引:4  
以Wistar大鼠为研究对象,对大鼠红细胞SOD活性、脑组织MAO-B活性、红细胞LPO含量进行测定,观察上述指标的随龄变化,甘草对老年大鼠上述指标的影响。结果表明:大鼠的SOD活性在其成长阶段随龄升高(P<0.01);红细胞LPO含量随龄增加(P<0.01);脑组织MAO-B活性随龄增加,甘草水煎剂能提高老年大鼠SOD活性,降低LPO含量,降低MAO-B活性(P<0.01)。不同的用药时间对上述指标的影响无明显差异(P>0.05)。提示甘草可以抗衰老。  相似文献   

11.
A Zhou  L Yu  J Li  J Zhang  H Wang 《Hypertension research》2000,23(4):391-397
The present study compared renoprotective effects of angiotensin II type I receptor antagonist (AT1RA) with angiotensin converting enzyme inhibitor (ACEI), and their influence on the renin-angiotensin-system (RAS). Experimental nephrotic syndrome was induced in SD rats by repeated peritoneal injections of puromycin. Twenty-eight rats were randomly divided into four groups: normal control, nephrotic control, ACEI-treated, and AT1RA-treated groups. Serum, urine, and renal tissue were collected for study at the end of 12 weeks. Compared with those of the nephrotic control group, urinary protein was less and renal function was better in both treated groups. The glomerular and interstitial damage indexes of both ACEI- and AT1RA-treated rats were lower than those of nephrotic control rats, with no significant difference observed between the two treated groups. Local renal ACE activity and angiotensin II concentration were elevated in nephrotic rats (p< 0.01). However, there is no significant difference in circulating RAS, renal tissue renin, and aldosterone between the normal control and nephrotic control rats. As expected, enalapril inhibited the local renal ACE activity and significantly decreased angiotensin II (p< 0.01). Intrarenal ACE activity and angiotensin concentration returned to normal levels after treatment with irbesartan (p< 0.01). In conclusion, AT1RA and ACEI have comparable renal protective effects, and these protective effects were associated with the inhibition of intrarenal ANG II.  相似文献   

12.
Elased KM  Cool DR  Morris M 《Hypertension》2005,46(4):953-959
This article demonstrates the applicability of quantitative proteomics to assays of proteolytic enzyme activity. A novel assay was developed for measurement of renin and angiotensin-converting enzyme (ACE) activity in plasma. The method was validated in animal models associated with alterations of the renin angiotensin system (RAS). Using surface-enhanced laser desorption/ionization time of flight mass spectrometry (SELDI-TOF-MS) with a ProteinChip Array technology, plasma renin and ACE1 could be measured in <0.5 microL of plasma. Plasma is incubated with peptide substrates for renin and ACE, tetradecapeptide (TDP), and angiotensin I (Ang I), respectively. The reactions mixtures are spotted onto the ProteinChip WCX2 and detected using SELDI-TOF-MS. Peak height or area under curve for TDP, Ang I, and angiotensin II (Ang II) peaks are measured. There was a linear relationship between disappearance of substrate and appearance of products for both renin and ACE (R2=0.95 to 0.98). ACE1 activity was blocked with chelating agents (EDTA and 1,10 phenanthrolene), indicating action of a metalloprotease. The ACE1 inhibitor, captopril, selectively blocked ACE1. Renin activity was specifically blocked with renin inhibitor and was not affected by phenanthrolene or captopril. Animal models tested were Ang AT1a receptor-deficient and streptozotocin (STZ) diabetic mice. Plasma renin activity was increased >2-fold in AT1a(-/-) as compared with AT1a(+/+). In STZ diabetic mice, ACE1 was increased 2-fold as compared with controls. The advantage of the method is that it is tagless, does not require additional purification steps, and is extremely sensitive. The approach can be multiplexed and used for identification of novel substrates/inhibitors of the RAS.  相似文献   

13.
Aims/hypothesis The angiotensin II (type 1) (AT1) receptor mediates many biological effects of the renin–angiotensin system (RAS), leading to remodelling of cardiac tissue. The present study was designed to analyse changes in the function and expression of the AT1 receptor as principal effector of the RAS in myocardium from type 2 diabetic patients compared with non-diabetic myocardium as control. In addition, we determined the effect of treatment with ACE inhibitors or AT1 receptor blockers on expression levels of the receptor in diabetic patients.Methods Gene expression of the AT1 receptor was analysed by quantitative RT-PCR and protein expression was determined by immunoblot analysis in human right atrial myocardium. We investigated functional coupling of the receptors by measuring contractility in isolated trabeculae stimulated with increasing concentrations of angiotensin II.Results Diabetic myocardium showed a significant increase in protein expression (170 ± 16% of control) and median mRNA expression (186% of control) of the AT1 receptor. The additional receptors were functionally coupled, resulting in a stronger inotropic response upon stimulation with angiotensin II (89 ± 5.5% vs 29 ± 1.6% in controls), whereas receptor affinity was similar in both groups. However, myocardium from diabetic patients treated with ACE inhibitors or AT1 receptor blockers showed no increase in AT1 receptor expression.Conclusions/interpretation AT1 receptor expression in myocardium of type 2 diabetic patients is dynamic, depending on the level of glycaemic control and the activity of the RAS. These findings could at least in part explain the strong therapeutic benefit of RAS inhibition in diabetic patients.  相似文献   

14.
Blood pressure and genetic factors are important factors for diabetic nephropathy. We investigated the relationship between the efficacy of renin angiotensin system (RAS) inhibitors and angiotensin-converting enzyme (ACE) genotypes. Patients with type 2 diabetes without proteinuria, were treated with RAS inhibitors, the first being an ACE inhibitor (ACEI) and the second, an angiotensin II (ATII) receptor blocker (ARB) for 8 weeks each. There was no significant difference (except serum ACE activity) between the two treatments. However, by analysis segregated with ACE gene polymorphism, ARB significantly decreased transforming growth factor-beta1 (TGF-beta) compared to ACEI in patients with the I/I genotype but not in patients with the D/I+D/D genotype. DeltaATII and DeltaTGF-beta have a negative correlation with the I/I genotype and a positive correlation with the D/I+D/D genotypes. These correlation coefficients are significantly different. We suggest that in I/I patients, TGF-beta was reduced by ARB via effects on (ATII) type 2 receptors (AT2). In our experiments, the effect of ARB on TGF-beta reduction was only detected by segregation of ACE genotypes. This indicates that the selection of medicine in light of a patient's genotype is important in treating diabetic nephropathy.  相似文献   

15.
The renin-angiotensin system (RAS) has been unequivocally implicated as a mediator of diabetic complications. The present study was designed to evaluate the RAS in non-insulin dependent diabetic patients with diabetic nephropathy. Plasma renin activity, plasma angiotensin II and serum angiotensin-converting enzyme (ACE) activity were measured in 45 non-insulin dependent diabetes mellitus (NIDDM) patients and 15 healthy non-diabetic controls. Diabetics were subdivided into 15 normoalbuminuric NIDDM subjects, 15 NIDDM patients with microalbuminuria and 15 diabetics with macroalbuminuria. Mean plasma renin activity for macroalbuminuric diabetics (0.65+/-0.10 ng/ml/hr) was significantly reduced than the controls (1.28+/-0.37 ng/ml/hr) (P<0.001), the diabetic group with microalbuminuria (1.08+/-0.48 ng/ml/hr) (P<0.05) and normoalbuminuric patients (1.56+/-0.82 ng/ml/hr) (P<0.001). A significant negative correlation was obtained between serum creatinine and plasma renin activity (r=-0.842, p<0.001) in macroalbuminuric NIDDM patients. Plasma angiotensin II was significantly decreased in non-complicated diabetics compared to healthy controls (4.36+/-1.49 pg/ml vs 14.87+/-3.48 pg/ml respectively, p<0.001). Non-insulin dependent diabetic patients with nephropathy had significantly higher plasma angiotensin II levels (28.99+/-5.88 pg/ml) than non-complicated diabetics (p<0.001). Serum ACE activity was increased in 53.3% of NIDDM patients. All diabetic groups showed increased serum ACE activity (normoalbuminuric NIDDM 114.9+/-28.3 nmol/min/ml, microalbuminuric NIDDM 127.9+/-31.2 nmol/min/ml and macroalbuminuric NIDDM 127.0+/-29.3 nmol/min/ml) when compared to the normal control group (76.3+/-16.5 nmol/min/ml) (p<0.001). No significant difference in serum ACE activity was obtained between normoalbuminuric and nephropathic diabetics or between diabetics with and without retinopathy. No significant correlation was obtained between serum ACE activity and blood pressure, blood glucose level and duration of diabetes. Thus plasma renin activity is decreased in diabetic nephropathy and negatively correlates with serum creatinine. Plasma angiotensin II is decreased in normoalbuminuric diabetics and elevated in diabetic nephropathy. Serum ACE activity is raised in NIDDM patients with no relation to albumin excretion rate. The role of increased ACE activity in NIDDM remains to be established.  相似文献   

16.
Renin-angiotensin system revisited   总被引:3,自引:0,他引:3  
New components and functions of the renin-angiotensin system (RAS) are still being unravelled. The classical RAS as it looked in the middle 1970s consisted of circulating renin, acting on angiotensinogen to produce angiotensin I, which in turn was converted into angiotensin II (Ang II) by angiotensin-converting enzyme (ACE). Ang II, still considered the main effector of RAS was believed to act only as a circulating hormone via angiotensin receptors, AT1 and AT2. Since then, an expanded view of RAS has gradually emerged. Local tissue RAS systems have been identified in most organs. Recently, evidence for an intracellular RAS has been reported. The new expanded view of RAS therefore covers both endocrine, paracrine and intracrine functions. Other peptides of RAS have been shown to have biological actions; angiotensin 2-8 heptapeptide (Ang III) has actions similar to those of Ang II. Further, the angiotensin 3-8 hexapeptide (Ang IV) exerts its actions via insulin-regulated amino peptidase receptors. Finally, angiotensin 1-7 (Ang 1-7) acts via mas receptors. The discovery of another ACE2 was an important complement to this picture. The recent discovery of renin receptors has made our view of RAS unexpectedly complex and multilayered. The importance of RAS in cardiovascular disease has been demonstrated by the clinical benefits of ACE inhibitors and AT1 receptor blockers. Great expectations are now generated by the introduction of renin inhibitors. Indeed, RAS regulates much more and diverse physiological functions than previously believed.  相似文献   

17.
The renin-angiotensin aldosterone system (RAAS) is well-established to be involved in diabetic nephropathy. Several abnormalities in the RAAS have been described in diabetes mellitus, including an abnormal aldosterone to renin ratio, elevated angiotensin I-converting enzyme (ACE) levels, and altered angiotensin II sensitivity. Whereas the renoprotective properties of ACE-inhibition in diabetic nephropathy have been demonstrated more than a decade ago, somewhat surprisingly, the role of ACE-activity in the pathogenesis of diabetic nephropathy is not well established. This paper addresses the possible functional impact of genetic and environmental increased in ACE activity in the pathogenesis of diabetic renal damage, in the context of the various other abnormalities in the RAAS in diabetes. Human and experimental data on circulating and tissue ACE in diabetes are reviewed, as well as the associations of ACE with angiotensin I conversion, with pathophysiological responses, and with renal end organ damage. New data from our laboratory provide evidence for interaction between genetical regulation of ACE activity by the ACE (I/D) genotype and diabetes as an environmental factor. Moreover, for functional effects of the elevated ACE activity in terms of increased conversion of angiotensin I to angiotensin II. The effects of enhanced generation of angiotensin II are modulated by the angiotensin II-subtype I receptor (AT1R). Altered AT1R sensitivity has been reported in diabetes that may further modu-late the eventual effects of elevated ACE. Epidemiological data on the association of genetically elevated ACE activity with diabetic nephropathy provide support for a pathogenetic role of elevated ACE activity in diabetic nephropathy. Together, the data suggest that differences in ACE expression and activity, resulting from both genetic and environmental factors and their interaction can modulate the pathogenesis of diabetic nephropathy. Unravelling the nature of this interaction, with focus on modifiable environmental factors, may help to ameliorate the risk for nephropathy in diabetes.  相似文献   

18.
BACKGROUND: Vascular (interstitial) angiotensin (ANG) II production depends on circulating renin-angiotensin system (RAS) components. Mannose 6-phosphate (man-6-P) receptors and angiotensin II type 1 (AT(1)) receptors, via binding and internalization of (pro)renin and ANG II, respectively, could contribute to the transportation of these components across the endothelium. OBJECTIVE: To investigate the mechanism(s) contributing to transendothelial RAS component transport. METHODS: Human umbilical vein endothelial cells were cultured on transwell polycarbonate filters, and incubated with RAS components in the absence or presence of man-6-P, eprosartan or PD123319, to block man-6-P, AT(1) and angiotensin II type 2 (AT(2)) receptors, respectively. RESULTS: Apically applied (pro)renin and angiotensinogen slowly entered the basolateral compartment, in a similar manner as horseradish peroxidase, a molecule of comparable size that reaches the interstitium via diffusion only. Prorenin transport was unaffected by man-6-P. Apical ANG I and ANG II rapidly reached the basolateral fluid independent of AT(1) and AT(2) receptors. Basolateral ANG II during apical ANG I application was as high as apical ANG II, whereas during apical ANG II application it was lower. During basolateral ANG I application, ANG II generation occurred basolaterally only, in an angiotensin-converting enzyme (ACE)-dependent manner. CONCLUSIONS: Circulating (pro)renin, angiotensinogen, ANG I and ANG II enter the interstitium via diffusion, and interstitial ANG II generation is mediated, at least in part, by basolaterally located endothelial ACE.  相似文献   

19.
20.
慢性缺氧性肺动脉高压大鼠内皮素肾素血管紧张素变化   总被引:2,自引:0,他引:2  
为研究组织局部肾素血管紧张素系统(RAS)和内皮素对缺氧性肺动脉高压(PAH)的影响。采用常压缺氧PAH动物模型,观察血液、右心室、肺组织肾素活性(RA)、血管紧张素Ⅱ(AngⅡ)、血管紧张素转换酶(ACE)及内皮素(ET)含量变化和西拉普利(Cilazapril)的治疗作用。结果发现缺氧时血RA与对照组无显著差别,AngⅡ、ET升高,ACE下降。右心室肌的RA、AngⅡ、ET升高。肺组织RA、AngⅡ升高,而ET、ACE与对照组无显著差别,Cilazapril使血、肺组织ACE、心肌AngⅡ降低。结论为1.心肺组织RAS与PAH的发生有关;2.Cilazapril治疗PAH有效。  相似文献   

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