共查询到18条相似文献,搜索用时 125 毫秒
1.
目的本研究观察不同月龄自发性高血压大鼠(SHR)肾脏ALR和ALR表达,初步探讨AT1R和AT2R在高血压发生、发展过程中的可能作用。方法1月龄组(S1)、2月龄组(S2)、3月龄组(S3)、6月龄组(S6)和9月龄组(墨)雄性SHR共5组,每组各6只,各组均有相应月龄匹配的Wistar-Kyoto大鼠(WKY)作对照。采用RBP-I型大鼠血压心率测定仪测量大鼠尾动脉收缩压(SBP);放免法测定血浆血管紧张素Ⅱ(AngⅡ);免疫组化染色结合计算机图像分析方法测定肾脏AT1R和ALR表达水平。结果(1)SHR SBP随着月龄的增加而上升,S6后趋于稳定。(2)1个月后SHR血浆AngⅡ浓度均高于S1(P〈0.05),而S2、S3、S6和S9之间无明显差别(P〉0.05);1个月后SHR血浆AngⅡ浓度均高于相应配对的WKY组(P〈0.05);而WKY各月龄组均无明显差别(P〉0.05)。(3)SHR肾脏AT1R随着月份的增加而增加(P〈0.05),且高于相应配对的WKY组(P〈0.05)。SHR肾脏ABR随着月份的增加而降低,S6明显降低(P〈0.05),S6和S9比较无明显差别(P〉0.05);且均低于相应配对的WKY组(P〈0.05)。WKY各月龄组AT1R和AT2R无明显差别(P〉0.05)。结论SHR肾脏AT1R表达水平比WKY高,并随着年龄的增加而递增;AT2R表达水平比WKY低,并随着年龄的增加而降低。 相似文献
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目的:通过观察血管紧张素转化酶(ACE)和血管紧张素转化酶2(ACE2)在Wistar-京都种大鼠(WKY)和自发性高血压(SHR)大鼠心脏组织中表达的差异,探讨ACE与ACE2在自发性高血压大鼠高血压形成中的作用。方法:自由饲喂14周龄WKY和SHR雄性大鼠一周后,用BSN-II多通道无创测压系统测定大鼠收缩压(SBP)、舒张压(DBP)、心率(HR)并称重;放免法测定血浆中血管血管紧张素Ⅱ(AngII)含量;Real-time PCR测定心脏组织中ACE,ATI受体(ATIR),ACE2和Mas受体(MasR)mRNA的表达水平;Western blot法检测心脏组织中ACE2的蛋白表达。结果:SHR大鼠SBP和DBP均显著高于WKY大鼠(P〈0.01);两组大鼠心率和体重无显著差异(P〉0.05);SHR大鼠血浆中AngII含量显著升高(P〈0.05);与WKY大鼠相比,SHR大鼠心脏中ACE mRNA表达均显著升高(P〈0.05),ACE2的mRNA和蛋白表达水平均显著下降(P〈0.05);心脏组织中AT1R和MasR的mRNA表达没有显著性变化(P〉0.05)。结论:ACE与ACE2表达失调是SHR大鼠高血压形成的主要原因之一,其机理可能与局部组织RAS系统ACE-AngII-AT1R通路过度活跃,ACE2-Ang(1-7)-MasR通路相对不足有关。 相似文献
3.
自发性高血压大鼠心肌肥厚和心肌MAPK、AngⅡ的关系 总被引:5,自引:1,他引:5
放免法测定自发性高血压大鼠(SHR)血浆及心肌血管紧张素Ⅱ(AngⅡ)含量,凝胶内磷酸化法测定心肌丝裂素活化蛋白激酶活性(MAPK),以心脏重/体重表示心肌肥厚程度。结果表明:与4个月的WKY大鼠比较,4个月的SHR血浆和心肌组织AngⅡ及心肌MAPK活性分别增加了218.6%、101.2%和107.0%,心肌肥大程度严重,其中MAPK活性与心肌肥大程度呈明显正相关。提示4个月SHR心肌肥厚可能是 相似文献
4.
目的: 研究有氧运动训练对自发性高血压大鼠(SHR)肾脏纤维化影响, 探讨有氧运动对高血压肾损害的保护作用。方法: 8周龄雄性SHR和同龄Wistar京都大鼠(WKY)随机分为4组(n=6):安静WKY对照组(WKY-S)、安静SHR对照组(SHR-S)、低强度运动组(SHR-L)和中强度运动组(SHR-M)。SHR-L组、SHR-M组分别以14 m/min(最大有氧速度的35%)、20 m/min(最大有氧速度的50%)在0°坡度的运动跑步机上跑步,共运动14周,每周5次,每次60 min,WKY-S和SHR-S组安静饲养。14周后,运动训练结束72 h后检测大鼠血压;之后取血和肾脏检测血清肌酐SCr和尿素氮BUN含量,苏木精与伊红(HE)染色观察肾组织形态,Masson染色观察肾组织胶原沉积情况,计算肾脏胶原容积分数(CVF),检测肾脏 AngⅡ、AT1R、TGF-β、α-SMA、CTGF蛋白表达。结果: 与WKY-S组相比,SHR-S组的血压和血清SCr、BUN含量、肾脏CVF水平和AngⅡ、AT1R、TGF-β、α-SMA、CTGF蛋白表达均明显升高(P<0.05);与SHR-S组相比,SHR-L组和SHR-M组血压和血清SCr、BUN含量、肾脏CVF水平和AngⅡ、AT1R、TGF-β、α-SMA、CTGF蛋白表达均明显下降(P<0.05)且SHR-M组下降趋势更明显(P<0.05)。结论: 有氧运动可通过抑制肾脏AngⅡ-AT1R-TGF-β通路,改善自发性高血压大鼠的肾纤维化与肾功能。 相似文献
5.
肾性和自发性高血压大鼠心肌肥大前后心肌Gαq/11含量的变化 总被引:1,自引:0,他引:1
目的 :探讨Gαq/11在不同原因所致心肌肥大中的变化。方法 :两肾一夹肾性高血压大鼠 (RHR)和自发性高血压大鼠(SHR)模型 ,测定动脉血压和心肌肥大指数 ,放免法测定心肌血管紧张素II(AngII)含量 ,免疫印迹法测定心肌Gαq/11含量。 结果 :RHR术后 1周动脉血压、心肌肥大指数及Gαq/11含量与假手术组无差异 ,心肌AngII含量显著升高 (P <0 .0 1) ;术后 8周上述各指标均较假手术组升高。 12周龄SHR动脉血压、心肌肥大指数和AngⅡ含量均较同龄WKY升高 (P均 <0 .0 1) ,但心肌Gαq/11含量却无明显变化 ;4周龄时上述各指标与同龄对照相比均无明显差异。 结论 :Gαq/11在肾性和自发性高血压心肌肥大中有不同变化。 相似文献
6.
目的对感觉神经损伤性盐敏感性高血压大鼠的心肌、肾脏组织中的血管紧张素Ⅱ1型受体(AT1R)在mRNA和受体水平的表达进行检测,探讨AT1R与盐敏感性高血压的关系。方法用乳鼠皮下注射辣椒辣素法建立模型。哺乳期后,大鼠被随机分成4组:对照+正常盐饮食组(CON-NS);对照+高盐饮食组(CON-HS);辣椒辣素+正常盐饮食组(CAP-NS);辣椒辣素+高盐饮食组(CAP-HS)。至7周龄(分组饲养后第4周)处死大鼠,免疫组织化学方法和反转录-聚合酶链式反应(RT-PCR)分别检测大鼠心肌和肾脏AT1R蛋白,以及AT1 R mRNA的表达。结果①Wistar大鼠在给予不同程度的感觉神经损伤和饲料干预后,各组大鼠尾部收缩压均有明显增加,最终CAP-HS组的尾收缩压显著高于其他三组(P〈0.01)。②免疫组织化学结果显示,CAP-HS组组织有显著的AT1R蛋白表达(P〈0.01);CON-HS组肾脏、心肌组织中AT1R蛋白表达高于CON-NS组(P〈0.05)。③RT-PCR检测基因表达,与对照组CON-NS相比,实验组CAP-HS的AT1R mRNA表达显著升高(P〈0.01);CON-HS组肾脏、心肌组织中AT1 R mRNA表达有显著性(P〈0.05)。结论感觉神经损伤性盐敏感性高血压大鼠心、肾AT1R表达升高,AT1R表达水平的差异可能与盐敏感性高血压的形成有关。 相似文献
7.
目的 观测自发性高血压大鼠心肌纤维化时序动态变化.方法 纳入4周龄SPF级雄性自发性高血压大鼠(spontaneously hypertensive rats,SHR)45只、京都种Wistar大鼠(Wistar Kyoto rats,WKY)35只,随机分笼饲养至42周,分别于预设时点尾套法监测收缩压,超声心动图监测... 相似文献
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9.
自发性高血压大鼠心肌和血管组织牛磺酸的转运障碍 总被引:2,自引:0,他引:2
在自发性高血压大鼠(SHR)的心肌和主动脉血管组织上观察牛磺酸(taurine)转运和牛磺酸转运体(taurine transporter,TAUT) mRNA 的改变,结果显示,与对照组WKY大鼠相比,SHR组血浆牛磺酸水平和牛磺酸释放量增加,而心肌和血管组织牛磺酸水平和TAUT mRNA含量均降低,牛磺酸最大转运速率(Vmax)分别低24%和35%(P<0.05),米氏常数(Km)值分别高16%和39%(P<0.05),这些结果提示,SHR的心肌和血管组织牛磺酸转运障碍可能与TAUT活性和亲和力降低及TAUT基因水平的下调有关。 相似文献
10.
自发性高血压大鼠中枢血管紧张素Ⅱ的变化对中枢肾上腺素... 总被引:1,自引:0,他引:1
The content of norepinephrine (NE) and epinephrine (E) in the brain of spontaneously hypertensive rats has proved abnormal, but the cause remained unknown. It was shown in the recent work that NE content in pons, posterior hypothalamus, nucleus caudatus and E concentration in medulla oblongata, anterior and posterior hypothalamus of 12-week old stroke-prone spontaneously hypertensive rats (SHRSP) were much higher than those of age-matched Wister-Kyoto rats (WKY). SHRSP also showed higher levels of systolic blood pressure (SBP) and brain angiotensin II (A II) than WKY. Intracerebroventricular (icv) perfusion of angiotensin-converting enzyme inhibitor captopril (20 micrograms for each time and three times for each day for four weeks) inhibited the synthesis of brain A II and reduced SBP and NE, E contents in all examined brain areas in SHRSP and WKY. However, the effects of chronically perfused captopril on SBP and brain NE, E levels in SHRSP were much more significant than in WKY. The results indicate that the modulatory effects of central renin-angiotensin system (RAS) on central adrenergic and noradrenergic system might be overactivated in SHRSP, which might partially responsible for the abnormally high levels of NE, E in some of the brain areas of SHRSP. 相似文献
11.
Angiotensin II Type 1 Receptor mRNA Levels in the Brains of Normotensive and Spontaneously Hypertensive Rats 总被引:4,自引:0,他引:4
Abstract: The type 1 angiotensin II (All) receptor (AT1 -R) has been implicated in the physiological actions mediated by All in the brain. In view of the reported hyperactivity of the brain All system in the spontaneously hypertensive rat (SHR), we compared the expression of AT,-R mRNAs in the brains of normotensive [Wistar Kyoto (WKY)] and SHR animals. Northern blot analysis showed about three- and ∼20-fold increases in the levels of AT1 -R mRNAs from the hypothalamus and brainstem areas, respectively, of the SHR compared with the WKY rat brain. This was attributable to greater levels of both AT,1A - and AT,1B -R mRNA subtypes in these areas from the SHR. These observations suggest that increased All receptor levels in SHR brain may, in part, be a result of increased expression of the AT1 -R gene. 相似文献
12.
目的:探讨自发性高血压大鼠(Spontaneously Hypertensive Rat,SHR)肠系膜微静脉白细胞-内皮细胞相互作用和微淋巴管收缩的特性。方法:取8周龄Wistar大鼠、8周龄SHR(SHR8W)和13周龄SHR(SHR13W),麻醉、固定并暴露肠系膜后,微循环显微镜下观察肠系膜微循环并录像;回放录像,计算微静脉白细胞滚动数和滚动的白细胞-内皮细胞接触时间(Rolling leukocyte-endothelial contact time,RLECT),用Vas Track自动测量系统对微淋巴管口径进行动态测量,并计算微淋巴管收缩特性指标。结果:SHR13W的白细胞滚动数显著低于Wistar;SHR8W和SHR13W的RLECT均显著低于Wistar,且SHR13W的RLECT显著低于SHR8W;进一步按照管径分级后,三组间白细胞滚动数在10~20μm管径级别下未见差异;各个管径级别下,SHR8W和SHR13W的RLECT均未见差异。SHR13W的淋巴管收缩分数显著低于Wistar和SHR8W;SHR8W及SHR13W的总收缩活性指数均显著低于Wistar;SHR13W的淋巴管动力指数显著低于Wistar。结论:SHR肠系膜微静脉白细胞滚动数及RLECT减少,其中白细胞滚动数在不同管径级别微静脉中的分布不均匀,而RLECT随SHR周龄降低,意味着SHR淋巴管收缩功能降低。 相似文献
13.
目的探讨自发性高血压大鼠(SHR)是否同时适用抗高血压药物单次给药的快速评价和连续给药的降压效果评价。方法SHR大鼠分组给药后,用Powlab/16sp测量单次和多次给药后不同时间点SHR大鼠SAP、DAP、BMP和HR的变化。结果卡托普利单次给药1~2 h内对收缩压和舒张压有明显的降压作用(P〈0.05),而连续给药随着给药时间延长给药28 d降压作用更为明显(P〈0.01)。结论自发性高血压大鼠既可用于降压药连续给药的药效学评价,也适用于单次给药的降压药快速筛选。 相似文献
14.
Hideyuki Kobayashi Keiko Take Akihiko Wada Futoshi Izumi Maria Sandra Magnoni 《Journal of neurochemistry》1984,42(6):1655-1658
Abstract: Angiotensin-converting enzyme (ACE) activity in brain microvessels of spontaneously hypertensive rats (SHR) and Wistar Kyoto (WKY) controls was measured. Cerebral microvessels, prepared from the cerebral cortices by the albumin flotation and glass bead filtration technique, were free of neuronal and glial elements. ACE activity in brain microvessels of SHR was lower than that of WKY. A Woolf-Augustinsson-Hofstee plot showed that the reduction of the enzyme activity in SHR was due to a 30% decrease in Vmax without any change in Km for substrate. The decrease of ACE activity in brain micro-vessels of SHR may indicate an impairment of the central renin-angiotensin system and may be related to cerebral microvascular dysfunctions occurring in hypertension. 相似文献
15.
John W. Wright Margaret J. Sullivan Charles R. Bredl Jodie M. Hanesworth Laurie L. Cushing Joseph W. Harding 《Journal of neurochemistry》1987,49(2):651-654
This study was designed to evaluate the hypothesis that impaired brain angiotensin signal termination contributes to the sustained blood pressure elevations noted in the genetically hypertensive rat model of human essential hypertension. A technique that combined the intracerebroventricular injection of [125I]angiotensins, followed by focused microwave fixation to stop all peptidase activity and subsequent HPLC analyses, was used for determining half-lives of [125I]angiotensin II and [125I]angiotensin III in the ventricular space. The results indicate that the spontaneously hypertensive rat evidenced significantly longer half-lives for intracerebroventricularly injected [125I]angiotensin II over those measured for the Wistar-Kyoto and Sprague-Dawley normotensive rat strains: 45.0, 27.2, and 25.0 s, respectively. This was also true for intracerebroventricularly administered [125I]angiotensin III: 19.5, 11.4, and 9.0 s, respectively. These results support the notion that a dysfunction in central aminopeptidase activity in the spontaneously hypertensive rat may result in prolonged half-lives of endogenously synthesized angiotensins II and III, which are known to serve as ligands at central angiotensin receptors responsible for the control of cardiovascular function. The extended half-lives of these ligands may contribute to the sustained elevations in blood pressure observed in this animal model. 相似文献
16.
《Peptides》2017
The renin-angiotensin system modulates insulin action. Angiotensin type 1 receptor exerts a deleterious effects while the angiotensin type 2 receptor (AT2R) appears to have beneficial effects providing protection against insulin resistance and type 2 diabetes. Although recent reports indicate that agonism of AT2R ameliorates diabetes and insulin resistance, the phenotype of AT2R-knockout mice seems to be controversial relating this aspect. Thus, in this study we have explored the role of AT2R in the control of insulin action. To that end, C57Bl/6 mice were administered the synthetic AT2R antagonist PD123319 for 21 days (10 mg/kg/day ip); vehicle treated animals were used as control. Glucose tolerance, metabolic parameters, in vivo insulin signaling in main insulin-target tissues as well as levels of adiponectin, TNF-α, MCP-1 and IL-6 in adipose tissue were assessed. AT2R blockade with PD123319 induced a marginal effect on glucose homeostasis but an important reduction in the insulin-induced phosphorylation of the insulin receptor and Akt in both liver and adipose tissue. Insulin signaling in skeletal muscle remained unaltered after treatment with PD123319, which could explain the minimal effect on glucose homeostasis induced by PD123319. Our current results reinforce the notion that the AT2R has a physiological role in the conservation of insulin action. 相似文献
17.
We compared the effect of immobilization stress on noradrenaline (NA) and 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG) content in two brain regions--diencephalon and pons-medulla oblongata--in young and adult spontaneously hypertensive rats (SHR) and Wistar-Kyoto rats (WKY). In SHR, NA content decreased with time after the onset of the stress, whereas levels of its metabolite MHPG increased. In WKY, NA and MHPG showed no change. The MHPG/NA ratio in both regions increased relative to the duration of the stress in SHR, whereas it remained almost constant in WKY. The rate of increase in the ratio was much higher in the diencephalon of adult (12-week-old) than of young (4-week-old) SHR. In SHR, NA turnover in the brain is readily affected by environmental stress, and these changes in the noradrenergic system may induce or sustain hypertension. 相似文献
18.
Abstract: Cerebral taurine biosynthesis in a spontaneously hypertensive rat (SHR) has been studied. Cysteine sulfinic acid (CSA) and cysteic acid (CA), possible key intermediates in taurine biosynthesis, were found in the rat brain, whereas no cysteamine-cystamine was detected. In the brain of SHR, a statistically significant decrease in the contents of CSA, CA, and taurine was noted in the cerebellum, hypothalamus, and striatum as compared with normotensive Wistar Kyoto rats. Similarly, it was demonstrated that the activity of cysteine dioxygenase, the enzyme catalyzing cysteine to CSA, was attenuated significantly in the same brain areas of SHR. In contrast, no alteration in the activity of CSA decarboxylase, the enzyme converting CSA to hypotaurine or CA to taurine, was observed. A decline in the percent conversion of [14 C]cysteine to [14 C]taurine was found also in tissue homogenates from the cerebellum, hypothalamus, and striatum of SHR, indicating that the declines in taurine content may be due to an attenuation of taurine biosynthesis, possibly at the step involving cysteine dioxygenase. 相似文献