肾素-血管紧张素系统与急性胰腺炎

肾素 血管紧张素系统 (RAS)是人体内一个经典的调节血压和体液平衡的系统 ,近年来在包括胰腺在内的许多组织中发现有局部RAS存在。胰腺RAS含有许多非经典的RAS组分 ,能影响胰腺的内外分泌功能。在急性胰腺炎中 ,RAS可能通过调节血供、氧分压、自由基、炎症介质等机制发挥一定作用 ,抑制其活性可能对胰腺有保护效果 ,对其进行更深入的研究将为临床治疗提供一些新的思路。     

肾素-血管紧张素系统与糖尿病肾病研究进展

肾脏内存在完整的肾素 血管紧张素系统 (RAS)。近年研究发现 ,RAS与糖尿病肾病 (DN)的关系密切。该系统不仅通过影响全身及肾脏局部的血流动力学 ,造成肾小球内高压 ,还与DN发病机制中的蛋白激酶C(PKC)学说、氧化应激 (OS)学说、细胞因子学说及遗传分子学说紧密相关。     

肾素-血管紧张素系统阻断与肾脏病

通过介绍血管紧张素Ⅱ（ＡⅡ）的产生途径、受体亚型等有关进展,比较阻断肾素血管紧张素系统不同方法的异同,探讨ＡⅡ１型受体拮抗剂（ＡＴ１ＲＡ）在降低血压及延缓肾脏疾病进展中的作用     

肾素血管紧张素系统与腹膜纤维化

肾素血管紧张素系统（RAS）是机体调节血管张力和钠水代谢的内分泌系统，随血液循环发挥作用。在慢性腹膜透析所致腹膜纤维化发病过程中，腹膜局部RAS激活，血管紧张素Ⅱ（ATⅡ）增加，促进转化生长因子β1（TGF-β1）分泌很可能是其中的重要发病机制之一。     

肾脏局部肾素-血管紧张素系统的研究进展

多年来,肾素-血管紧张素系统（renin-angiotensin sys—tem,RAS）在高血压发病及靶器官损害,尤其是。肾脏疾病进展中的作用一直是研究热点。长期以来,肾脏局部中存在独立的RAS系统,肾脏RAS的新成分及新作用机制不断被发现。近年研究表明,肾内RAS系统的不适当激活是高血压和肾损害发生的重要因素。本文旨在简要的总结近年肾脏局部RAS系统的激活在高血压及肾脏疾病发生中的主要研究进展。     

肾素血管紧张素系统与造血调控研究进展

肾素-血管紧张素系统（RAS）的主要生物学作用体现在对血压和水、电解质的调控上.近年来的研究表明,RAS参与造血调控,其主要活性物质血管紧张素Ⅱ（AngⅡ）促进红系造血,而其受体拮抗剂（ARB）和血管紧张素转换酶抑制剂（ACEI）抑制红系造血.     

肾素-血管紧张素系统组成的新认识及其在肾脏的作用

肾素-血管紧张素系统（rennin angiotensin system，RAS）是最重要的心血管系统体液调节机制之一，最近发现了这一系统的许多新成员，包括AngⅡ受体、ACE2、Ang（1～7），这些物质的发现和对其生理意义的研究让我们对RAS有了许多新的认识。RAS对肾脏作用的研究也日益增多，RAS对肾脏的非血流动力学作用，AngⅡ受体、ACE2和Ang（1-7）在肾脏中的作用成为目前研究的热点。     

大鼠烧伤后心肌局部肾素-血管紧张素系统的改变

目的观察烧伤早期心肌局部肾素-血管紧张素系统(RAS)变化及其对心肌肌浆网(SR)钙运转功能的影响,探讨烧伤早期心功能障碍的发病机制。方法大鼠随机分为对照组(8只,不予致伤),烧伤组(40只,致30%Ⅲ度烧伤),治疗组(40只,Lisinopril 灌胃3天后致30%Ⅲ度烧伤),测定烧伤前(对照组)及烧伤后3,8,24 h 左心功能变化,心肌组织血管紧张素转换酶(ACE)活性,血管紧张素Ⅱ(A_Ⅱ)及钙离子(Ca~(2 ))含量变化,测定心肌 SR Ca~(2 )-ATPase 活性,吸 SR Ca~(2 )运转功能的变化。结果烧伤组大鼠左心室内压变化最大速率(±dp/dt_(max))明显降低。心肌组织 ACE 活性、A_Ⅱ及 Ca~(2 )含量显著增加,心肌 SR Ca~(2 )-ATPase 活性降低,SR Ca~(2 )摄取减少。治疗组预防性给予 ACE 抑制剂 Lisinopril 可显著降低烧伤后心肌组织 ACE 活性,减少 A_Ⅱ产生,Ca~(2 )含量降低,增加SR Ca~(2 )-ATPase 活性,SR Ca~(2 )摄取增加,左心室功能明显改善。结论烧伤早期心肌局部 RAS 迅速激活,抑制 SR Ca~(2 )运转,可能是心肌 RAS 促进烧伤早期心功能障碍的作用机制之一。     

Improved islet morphology after blockade of the renin- angiotensin system in the ZDF rat

The renin-angiotensin system (RAS) has an important role in the endocrine pancreas. Although angiotensin II has significant effects on cell proliferation and apoptosis, the contribution of the RAS to changes in islet structure and function associated with type 2 diabetes is yet to be defined. This study examined the specific effects of RAS blockade on islet structure and function in diabetes. Thirty-six male Zucker diabetic fatty (ZDF) rats, 10 weeks of age, were randomized to receive the angiotensin-converting enzyme inhibitor perindopril (8 mg/l in drinking water; n = 12), irbesartan (15 mg/kg via gavage; n = 12), or no treatment (n = 12) for 10 weeks. Results were compared with lean littermates (ZL) (n = 12) studied concurrently. ZDF rats had increased intra-islet expression of components of the RAS correlating with increased intraislet fibrosis, apoptosis, and oxidative stress. Disordered islet architecture, seen in ZDF rats, was attenuated after treatment with perindopril or irbesartan. Islet fibrogenesis was also diminished, as measured by picrosirius staining and expression of collagens I and IV. Gene expression of transforming growth factor-beta1 was increased in the ZDF pancreas (ZL, 1.0 +/- 0.1; ZDF, 2.0 +/- 0.3; P < 0.05) and reduced after blockade of the RAS (ZDF + P, 1.3 +/- 0.2; ZDF + I, 1.5 +/- 0.1; vs. ZDF, both P < 0.05). Improvements in structural parameters were also associated with functional improvements in first-phase insulin secretion. These findings provide a possible mechanism for the reduced incidence of new-onset diabetes that has been observed in clinical trials of RAS blockade.     

卡托普利对急性胰腺炎大鼠肾素血管紧张素Ⅱ水平的影响

目的 观察急性胰腺炎大鼠血浆肾素、血管紧张素Ⅱ水平变化以及卡托普利的干预效应。方法 63只SD大鼠分对照组、急性胰腺炎组、卡托普利干预组三组,进行不同处理。急性胰腺炎组用十二指肠闭襻法制作急件胰腺炎模型,干预组在制模后立即腹腔注射卡托普利（5 mg/kg）,在病程不同时点测定血浆淀粉酶（AMY）、血浆肾素活性（PRA）、血管紧张素Ⅱ（Ang Ⅱ）水平,并观察胰腺组织病理学改变。结果（1）急性胰腺炎组随着病变的进展,胰腺炎病理由水肿向出血坏死发展,病程10h内,PRA、Ang Ⅱ水平升高,胰腺炎病理呈水肿性改变;10h后,Ang　Ⅱ继续升;苟,PRA却升高不显著,但仍保持高水平,病程24h胰腺炎病理呈出血坏死性改变,胰腺组织病理学评分的会高于10h（P<0.05）。（2）卡托普利干预组随着胰腺炎病变进展,血浆PRA、Ang Ⅱ水平低于急性胰腺炎组,胰腺组织病理学评分低于急性胰腺炎组（P<0.05）。结论 早期运用卡托普利可降低血浆肾素血管紧张素Ⅱ水平,对大鼠急性胰腺炎病变有保护作用。     

Progress in operative techniques in pancreas transplantation

Progress in operative techniques in pancreas transplantation.Pancreas transplantation has become a clinically established therapeutic procedure. The astonishing clinical success of pancreas transplantation resulted not only from new immunosuppressive strategies, but also from a remarkable progress in operative techniques. Pancreas segmental transplantation has been replaced by whole pancreas/duodenal transplantation. The exocrine secretion of the pancreas graft is not drained anymore into the bladder, but into the small intestine. Drainage of the venous blood from the graft containing high amounts of insulin is restored more and more not directly into the systemic venous circulation, but rather into the portal venous system. Thus, pancreas transplantation with enteral and portal drainage can be regarded as an operative technique which guarantees for the first time a totally physiologic situation in respect to the exocrine as well as endocrine secretions of the pancreas graft.     

Progress in transplantation of the pancreas (author's transl)

In the field of pancreas transplantation great progress has been made in recent years. While the transplantation of the whole organ has lost importance, success could be reached with the transplantation of isolated islets of Langerhans and with the segmental pancreas transplantation in experiments and in clinical practice. The present-day research is focused particularly on influencing the antigenicity of the endocrine pancreas tissue and on methodical problems of segmental pancreas transplantation.     

Targeting the renin angiotensin system in dialysis patients

Patients on chronic dialysis therapy have a dramatic excess cardiovascular risk compared to any other population, including those with overt diabetic nephropathy. Despite this, patients on dialysis are almost invariably excluded from trials evaluating the cardioprotective effect of novel treatments. Consistent evidence is available that inhibitors of the renin-angiotensin system, such as angiotensin-converting enzyme (ACE) inhibitors or angiotensin II receptor blockers (ARBs), are more cardioprotective than other antihypertensive agents in patients with chronic renal disease or diabetes (with or without renal involvement), but whether this applies also to patients on dialysis is unknown. However, clear evidence is available that ACE inhibitors and ARBs reduce morbidity and mortality in patients on dialysis with heart failure (HF) or atrial fibrillation (AF). Moreover, these drugs may preserve residual renal function in those with preterminal kidney failure as well as vascular access and peritoneal membrane function in those on extracorporeal or peritoneal dialysis, respectively. These drugs also show an excellent tolerability profile in this population. Thus, ACE inhibitors and ARBs are indicated in patients on dialysis with HF or AF. Available evidence suggests that they should be first-choice therapy in patients on dialysis with hypertension, though trials are still needed to formally demonstrate their superior cardioprotective effect over other antihypertensives in this population.     

The bladder angiotensin system in female rats: response to infusions of angiotensin I and the angiotensin converting enzyme inhibitor enalaprilat

PURPOSE: A local renin angiotensin (ANG) system has been identified in the bladder. To our knowledge little is known about this system. To define further the physiology of this system we performed this study. MATERIALS AND METHODS: The circulating and bladder tissue concentrations of ANG I and ANG II were examined in anesthetized Sprague-Dawley female rats in estrus, diestrus or pregnancy. Each was given an intravenous bolus infusion of ANG I, the ANG converting enzyme inhibitor enalaprilat or saline. RESULTS: The mean concentrations of ANG I and ANG II were markedly higher in bladder tissue than in whole blood at the highest levels in pregnancy. The concentration of ANG I and ANG II increased significantly in the bladder tissue and circulation after the ANG I infusion in estrus and diestrus. In pregnancy only circulatory ANG I increased, while circulatory ANG II, tissue ANG I and ANG II remained unchanged. Enalaprilat infusion was associated with an increased concentration of whole blood ANG I in all groups and decreased plasma ANG II in estrus and diestrus but not in pregnancy. The bladder tissue ANG I response was unchanged in all groups. Bladder tissue ANG II was decreased in estrus and diestrus but unchanged in pregnancy. CONCLUSIONS: These data support the hypothesis that ANG converting enzyme is deactivated and an alternate pathway is activated in pregnancy. The data also demonstrate that tissue absorption of ANG peptide is diminished in pregnancy. Compared with responses in similarly studied male rats the circulating conversion of ANG I to ANG II is delayed in female rats and responses to ANG converting enzyme inhibition are enhanced, thus, suggesting subtle differences in the sexes in the renin ANG system. Enalapril appears to have more effect at the tissue level in nonpregnant females than in pregnant females and male rats.     

胰腺囊性肿瘤诊治进展

目的：探讨胰腺囊性肿瘤的影像学特点和诊治方法,方法：参考目前关于胰腺囊性肿瘤的最新研究成果。结果：探讨了胰腺囊性肿瘤与胰腺假性囊肿的鉴别诊断,分别就浆液性囊性肿瘤（SCN）、粘液性囊性肿瘤(MCN)、导管内乳头状瘤(IPMN)和实性假乳头状瘤（SPN）的影像学特点和治疗方法进行了讨论,并且就内镜超声（EUS）、内镜超声引导下穿刺抽吸活检（EUS-FNA）以及囊液分析的诊断价值进行了深入探讨。结论：结论：尽管囊性病变有典型的影像学表现,但单一的影像检查的准确性还是有限的,CT、MR应与EUS相辅相成,而且还可行囊肿穿刺,分析囊液的成分,对于诊断不明确的病例,可以通过动态的影像检查来观察。     

Role of the renin angiotensin system in diabetic nephropathy

Diabetic nephropathy has been the cause of lot of morbidity and mortality in the diabetic population. The renin angiotensin system (RAS) is considered to be involved in most of the pathological processes that result in diabetic nephropathy. This system has various subsystems which contribute to the disease pathology. One of these involves angiotensin II (Ang II) which shows increased activity during diabetic nephropathy. This causes hypertrophy of various renal cells and has a pressor effect on arteriolar smooth muscle resulting in increased vascular pressure. Ang II also induces inflammation, apoptosis, cell growth, migration and differentiation. Monocyte chemoattractant protein-1 production responsible for renal fibrosis is also regulated by RAS. Polymorphism of angiotensin converting enzyme (ACE) and Angiotensinogen has been shown to have effects on RAS. Available treatment modalities have proven effective in controlling the progression of nephropathy. Various drugs (based on antagonism of RAS) are currently in the market and others are still under trial. Amongst the approved drugs, ACE inhibitors and angiotensin receptor blockers (ARBs) are widely used in clinical practice. ARBs are shown to be superior to ACE inhibitors in terms of reducing proteinuria but the combined role of ARBs with ACE inhibitors in diabetic nephropathy is under debate.