肾内肾素血管紧张素系统与糖尿病肾病

肾内肾素血管紧张素系统与糖尿病肾病刘艳芳综述潘长玉审校众所周知，肾素、血管紧张素系统（ＲＡＳ）在维持血压、体液及电解质平衡方面起着重要作用。近年来人们认为ＫＡＳ不仅属于内分泌范畴，通过血循环发挥生理作用，而且发现在肾上腺、心、脑、血管、肾脏等许多器官...     

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。探讨了ＡⅡⅠ型受体拮抗剂（ＡＴＩＲＡ）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     

阻断肾素-血管紧张素系统下调糖尿病大鼠肾组织转化生长因子β受体表达

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阻断肾素—血管紧张素系统下调糖尿病大鼠肾组织转化生长因子β？…

目的 探讨阻断肾素－血管紧张素系统（ＲＡＳ）对糖尿病大鼠肾组织转化生长因子β受体表达的影响。     

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、细胞因子遗传分子学说紧密相关。     

肾素血管紧张素系统在糖尿病肾病治疗中的研究进展

糖尿病肾病是引起终末期肾脏病（ ESRD）的重要病因之一。糖尿病肾病的发病与血糖的失控以及慢性高血糖状态相关。它的特点是肾小球的高灌注,肥大,基底膜增厚和肾小球高滤过,微量白蛋白尿的出现及随后的肾小球逐步硬化,然后是肾小管间质纤维化的发生,造成肾小球滤过率（ GFR ）下降。血管紧张素转换酶抑制剂（ ACEI）和血管紧张素受体阻滞剂（ ARBs）已被证实能有效控制糖尿病肾病的进展,并且广泛应用于临床实践,但联合应用ACEI与ARBs治疗糖尿病肾病还存在争议。     

Addition of atrasentan to renin-angiotensin system blockade reduces albuminuria in diabetic nephropathy

Although endothelin-receptor antagonists reduce albuminuria in diabetic nephropathy, fluid retention limits their use. Here, we examined the effect of atrasentan, a selective endothelin A receptor (ET(A)R) antagonist, on albuminuria in a randomized, double-blind, placebo-controlled trial of subjects with diabetic nephropathy already receiving stable doses of renin-angiotensin system (RAS) inhibitors. We randomly assigned 89 subjects with eGFR >20 ml/min per 1.73 m(2) and a urinary albumin-to-creatinine ratio (UACR) of 100 to 3000 mg/g to placebo or atrasentan (0.25, 0.75, or 1.75 mg daily) for 8 weeks. Compared with placebo, atrasentan significantly reduced UACR only in the 0.75- and 1.75-mg groups (P=0.001 and P=0.011, respectively). Compared with the 11% reduction in the geometric mean of the UACR from baseline to final observation in the placebo group during the study, the geometric mean of UACR decreased by 21, 42, and 35% in the 0.25-, 0.75-, and 1.75-mg atrasentan groups (P=0.291, P=0.023, and P=0.073, respectively). In the placebo group, 17% of subjects achieved ≥40% reduction in UACR from baseline compared with 30, 50, and 38% in the 0.25-, 0.75-, and 1.75-mg atrasentan groups, respectively (P=0.029 for 0.75 mg versus placebo). Peripheral edema occurred in 9% of subjects receiving placebo and in 14, 18, and 46% of those receiving 0.25, 0.5, and 1.75 mg atrasentan, respectively (P=0.007 for 1.75 mg versus placebo). In summary, atrasentan, at the doses tested, is generally safe and effective in reducing residual albuminuria and may ultimately improve renal outcomes in patients with type 2 diabetic nephropathy.     

The renin-angiotensin system and diabetic nephropathy

The renin-angiotensin system (RAS) has key regulatory functions for blood pressure and fluid homeostasis. In addition, dysregulation of the system can have maladaptive effects to promote tissue injury in chronic diseases such as hypertension, heart failure, and kidney disease. These actions for the RAS to promote disease pathogenesis are especially apparent in diabetic nephropathy, the most common cause of end-stage renal disease in the United States. Evidence of a role for the RAS in diabetic nephropathy comes from studies in animal models and randomized clinical trials showing efficacy of angiotensin-converting enzyme inhibitors and angiotensin-receptor blockers to slow the progression of renal disease. Widespread applications of these therapies to a range of renal diseases may have contributed to the recent reduction in the incidence rates for end-stage renal disease. We provide a general review of the RAS and its role in diabetic nephropathy.     

Dual blockade of the renin-angiotensin system in type 1 patients with diabetic nephropathy.

BACKGROUND: Albuminuria and hypertension are predictors of poor renal and cardiovascular outcome in patients with diabetes. Approximately 30% of type 1 patients with diabetic nephropathy (DN) have albuminuria >1 g/day, and blood pressure >135 and/or >85 mmHg despite antihypertensive therapy with recommended doses of ACE inhibitor (ACEI) and diuretics. We tested the effect of dual blockade of the renin-angiotensin system (RAS) in these patients. METHODS: We performed a randomised double blind crossover trial with 2 months treatment with Irbesartan 300 mg o.d. and placebo added on top of previous antihypertensive treatment. We included 21 type 1 patients with DN responding insufficiently to ACEI and diuretics, as defined above. At the end of each treatment period, albuminuria, 24-h blood pressure and glomerular filtration rate (GFR) were measured. RESULTS: Addition of 300 mg Irbesartan to the patients' usual antihypertensive therapy induced a mean reduction in albuminuria of 37% (95% CI 20-49, P<0.001); from 1574 mg/24 h (95% CI 1162-2132) to 996 mg/24 h (95% CI 699-1419), a reduction in 24-h blood pressure of 8 mmHg systolic (95% CI -2 to 18) and 5 mmHg diastolic (95% CI 1-9) (P=0.11 and 0.01, respectively) (from placebo, mean (SE) 146 (4)/80 (2) mmHg). GFR remained unchanged. Serum potassium increased (mean 4.3 to 4.6 mmol/l, P=0.02). Intervention to reduce serum potassium was needed in two patients with GFR <35 ml/min/1.73 m(2). Otherwise the dual blockade with Irbesartan was safe and well tolerated. CONCLUSIONS: Dual blockade of the RAS may offer additional renal and cardiovascular protection in type 1 patients with DN responding insufficiently to conventional antihypertensive therapy, including recommended doses of ACEI and diuretics.     

Dual blockade of the renin-angiotensin system versus maximal recommended dose of ACE inhibition in diabetic nephropathy

BACKGROUND: Albuminuria and hypertension are predictors of poor renal and cardiovascular outcome in diabetic patients. We tested whether dual blockade of the renin-angiotensin system (RAS) with both an angiotensin-converting enzyme (ACE) inhibitor and an angiotensin II receptor blocker (ARB) is superior to maximal recommended dose of ACE inhibitor in type 1 diabetic patients with diabetic nephropathy (DN). METHODS: We performed a randomized, double-blind, crossover trial with 8 weeks treatment with placebo and irbesartan 300 mg (once daily), added on top of enalapril 40 mg (once daily). We included 24 type 1 patients with DN. At the end of each treatment period, albuminuria, 24-hour blood pressure, and glomerular filtration rate (GFR) were measured. RESULTS: Values on ACE inhibitors + placebo were: albuminuria [mean (95% CI)], 519 (342 to 789) mg/24 hours; blood pressure [mean (SEM)], 131 (3)/74 (1) mm Hg, and GFR [mean (SEM)], 65 (5) mL/min/1.73 m2. Dual blockade of the RAS induced a reduction in albuminuria [mean (95% CI)] of 25% (15, 34) (P < 0.001), a reduction in systolic blood pressure of 8 mm Hg (4, 12) (P = 0.002), and a reduction of 4 mm Hg (2, 7) (P = 0.003) in diastolic blood pressure. GFR and plasma potassium remained unchanged during both treatment regimes. Dual blockade was safe and well tolerated. CONCLUSION: Dual blockade of the RAS is superior to maximal recommended dose of ACE inhibitors with regard to lowering of albuminuria and blood pressure in type 1 patients with DN. Long-term trials are needed to further establish the role of dual blockade of the RAS in renal and cardiovascular protection.     

Beneficial impact on cardiovascular risk factors by dual blockade of the renin-angiotensin system in diabetic nephropathy

BACKGROUND: Patients with diabetic nephropathy have a high risk of cardiovascular disease and end-stage renal disease. Dual blockade of the renin-angiotensin system (RAS) with both ACE inhibitors (ACE-I) and angiotensin II receptor blockers may offer therapeutic advantages. METHODS: Based on three double-blind randomized cross-over trials, we analyzed the short-term effects of dual blockade of the RAS on cardiovascular surrogate end points in 51 type 1 diabetic patients with diabetic nephropathy. RESULTS: Compared to ACE-I, dual blockade of the RAS decreased albuminuria 37% from 558 mg/24 hour, and lowered 24-hour blood pressure 7/5 mm Hg from 137/76 mm Hg (P < 0.01). In addition, dual blockade lowered total and LDL-cholesterol 0.3 from 5.4 mmol/L and 3.1 mmol/L, respectively (P < or = 0.01). The antialbuminuric response to dual blockade of the RAS was influenced by the insertion (I)/deletion (D) polymorphism in the ACE gene. CONCLUSION: Dual blockade of the RAS may offer additional cardiovascular and renal protection in type 1 diabetic patients with diabetic nephropathy. Determination of the ACE/ID genotype may help identify patients particularly sensitive to such therapy.     

Gene polymorphism of the renin-angiotensin system and progression of diabetic nephropathy

Good evidence exists that genetic predisposition is a major determinant in the development of renal and cardiovascular complications of diabetes. In particular, the role of familial predisposition is well established in diabetic nephropathy which may cluster within families, both in type I (IDDM) and in type II (NIDDM) diabetes. The genes responsible for predisposition to renal and cardiovascular complications are not known, but those of the renin-angiotensin system (RAS) are plausible candidates. Beside the large number of studies aimed at evaluating the role of polymorphisms in these genes, particularly in angiotensin-converting enzyme (ACE) gene, in development of renal disease, no clear-cut evidence has been provided until now. Furthermore, a number of trials have shown that ACE-inhibitors (ACEi) may reduce the rate of progression of renal failure. If the RAS genotype were able to foresee the response to ACEi it would provide new strategies for a specific treatment of subjects at higher risk.     

Angiotensinogen gene variation and renoprotective efficacy of renin-angiotensin system blockade in IgA nephropathy

BACKGROUND: Blockade of the renin-angiotensin system (RAS) is well documented to be renoprotective; however, not all patients with glomerulonephritis respond well to this therapy. The interindividual variation in response to the RAS blockade may be in part genetically determined, whereas the results have been controversial. METHODS: We investigated whether the therapeutic efficacy of angiotensin-converting enzyme (ACE) inhibitors and/or angiotensin receptor blocker on renal prognosis is modified by the angiotensinogen gene (AGT) polymorphism in immunoglobulin A nephropathy (IgAN). In total, 259 patients with histologically proven IgAN were analyzed for clinical manifestations, renal survival, and their associations with AGT A(-20)C and M235T. RESULTS: The renal prognosis of 110 patients, who received ACE inhibitors/angiotensin receptor blocker during their clinical course, was significantly better than those without ACE inhibitors/angiotensin receptor blockers despite higher blood pressures and heavier proteinuria. The Cox proportional hazards regression model showed an increased hazard ratio (HR) for urinary protein (more than 1.0 g/day) of 3.346 (P = 0.0001), hypertension of 1.949 (P = 0.01), deteriorated renal function of 3.040 (P < 0.0001), no ACE inhibitor/angiotensin receptor blocker administration of 2.725 (P = 0.0004), and the T235 and C(-20) haplotype of 1.608 (P = 0.0322). Only in patients carrying at least one M235 and A(-20) haplotype did the administration of ACE inhibitors/angiotensin receptor blockers have no significant effect on the prognosis of renal function (Kaplan-Meier, log rank test, chi2 = 0.700; P = 0.4028), whereas it was significant in patients who had other haplotypes of AGT (chi2 = 11.805; P = 0.0006). CONCLUSION: This study provides evidence that the M235T and A(-20)C genotype of AGT can influence the therapeutic efficacy of a RAS blockade on the renal survival in IgAN.     

You are what you eat: dietary salt intake and renin-angiotensin blockade in diabetic nephropathy

Interactions between sodium intake, the renin-angiotensin system, and renal and cardiovascular outcomes are incompletely understood. The analysis by Lambers Heerspink et al. shows that angiotensin receptor blockade improves diabetic nephropathy and cardiovascular disease more when dietary sodium intake is low, and suggests possible harm when sodium intake is high. These findings highlight dietary salt as a modifiable cardiovascular and renal risk factor and emphasize the need for detailed mechanistic studies.