Renal Functional Reserve Research Articles

Acute Kidney Injury in the Elderly: Pathogenesis, Diagnosis and Therapy

Elderly patients, especially those with chronic kidney disease, are at least a 3.5-fold higher risk for the development of acute kidney injury (AKI). With aging, renal functional reserve is lower owing to specific cellular changes that affect function. Molecular studies are elucidating these cellular changes and offer the prospect of designing novel therapeutics. The spectrum of AKI in elderly patients is wide but is over-represented by prerenal and postrenal (obstructive) etiologies. This reflects potentially nephrotoxic clinical variables, such as combordid states, impaired baseline renal function, polypharmacy and an increase in high-risk procedures. In this population, the development of AKI can lead to longer hospital stays, higher mortality rates and an increased risk for the development of chronic kidney disease and end-stage renal disease. Careful attention to clinical risk factors, avoidance of nephrotoxic insults and meticulous supportive care for patients who develop AKI is critical in alleviating the burden of this problem.

Opportunity the early diagnosis of renal disfunction and opportunity medical nephroprotecion with arterial hypertension

104 patients were divided into four groups of patients with arterial hypertension, with diabetes mellitus and with out diabetes mellitus. The diagnosis significance between renal function reserve and renal function was revealed. Application of combination antihypertension therapy( angiotensin converting enzyme inhibitors and indapamide) showed reliable lowering systolic and diastolic arterial hypertention on the phone the treatment which took place and nephroprotection effect connected with recover renal function reserve. The therapy significantly reduced to lowering the patients to 2.7 which have higher and very higher risk of cardiovascular morbidity and mortality of scale SCORE.

Is Cystatin-C A Reliable Prognostic Parameter in Terms of Renal Functional Reserve for Antenatally Diagnosed Infravesical Obstruction?

Purpose We investigated the prognostic power of cystatin-c in determining renal functional outcome in patients with antenatally diagnosed infravesical obstruction (IVO). Material and Methods A total of 10 fetuses (IVO group) with prenatal ultrasonographic findings of bladder outlet obstruction were enrolled to this study.Amniotic fluid and fetal urine samples were obtained in IVO group. Control group consisted of 25 fetuses, who have undergone amniocentesis for obstetric reasons.Three consecutive bladder punctures (48 hours apart) were performed to obtain fetal urine sample. In addition to standart prognostic parameters (sodium, chloride, calcium, protein, beta-2 microglobulin, osmolarity), cystatin-c was measured both in urine and amniotic fluid samples. Results Mean maternal age was 26.9 (22-33) years in IVO group and 28.2 (22-34) years in control group (p > 0.05). In IVO group (n = 10), 9 fetuses with poor prognostic parameters died either in-utero (n = 4) or early postnatally (n = 5). The only fetus with favorable parameters survived postnatally. His serum creatinine level was 0.2 mg/dl at 1 year follow-up after valve ablation. Mean fetal urine levels of cystatin-c was 1.59 ± 1.87, 1.39 ± 1.76 and 1.68 ± 1.79 mg/l in serial punctures. The difference between second and third bladder punctures was significant in terms of urine cystatin-c level (p = 0.015). Mean amniotic fluid cystatin-c level was 2.11 ± 0.4 mg/l in IVO group and 1.12 ± 0.20 mg/l in control group. There was a significant correlation between fetal urine (second puncture) and amniotic fluid in terms of cystatin-c level (p = 0.030, r = 0.717). Amniotic fluid cystatin-c level was significantly higher in fetuses with suspected infravesical obtsruction compared to control group (p Conclusions Amniotic fluid may represent fetal urine sample in suspected antenatal infravesical obstruction in terms of cystatin-c level.Amniotic fluid cystatin-c level was significantly higher in obstructed fetuses compared to normal controls. Cystatin-c level in amniotic fluid sample may be sufficient to give prognostic information in antenatally diagnosed infravesical obstruction.

Clinical Detection of Precataractous Lens Protein Changes Using Dynamic Light Scattering

To use dynamic light scattering to clinically assess early precataractous lens protein changes. We performed a cross-sectional study in 380 eyes of 235 patients aged 7 to 86 years with Age-Related Eye Disease Study clinical nuclear lens opacity grades 0 to 3.8. A dynamic light-scattering device was used to assess alpha-crystallin, a molecular chaperone protein shown to bind other damaged lens proteins, preventing their aggregation. The outcome measure was the alpha-crystallin index, a measure of unbound alpha-crystallin in each lens. The association of the alpha-crystallin index with increasing nuclear opacity and aging was determined. There was a significant decrease in the alpha-crystallin index associated with increasing nuclear lens opacity grades (P < .001). There were significant losses of alpha-crystallin even in clinically clear lenses associated with aging (P < .001). The standard error of measurement was 3%. Dynamic light scattering clinically detects alpha-crystallin protein loss even in clinically clear lenses. alpha-Crystallin index measurements may be useful in identifying patients at high risk for cataracts and as an outcome variable in clinical lens studies. The alpha-crystallin index may be a useful measure of the protective alpha-crystallin molecular chaperone reserve present in a lens, analogous to creatinine clearance in estimating renal function reserve.

Nephrectomy Elicits Impact of Age and BMI on Renal Hemodynamics: Lower Postdonation Reserve Capacity in Older or Overweight Kidney Donors

Renal functional reserve could be relevant for the maintenance of renal function after kidney donation. Low-dose dopamine induces renal vasodilation with a rise in glomerular filtration rate (GFR) in healthy subjects and is thought to be a reflection of reserve capacity (RC). Older age and higher body mass index (BMI) may be associated with reduced RC. We therefore investigated RC in 178 consecutive living kidney donors (39% males, age 48 +/- 11 years, BMI 25.5 +/- 4.1). RC was determined as the rise in GFR ((125)I-iothalamate), 4 months before and 2 months after donor nephrectomy. Before donor nephrectomy, GFR was 114 +/- 20 mL/min, with a reduction to 72 +/- 12 mL/min after donor nephrectomy. The dopamine-induced rise in GFR of 11 +/- 10% was reduced to 5 +/- 7% after donor nephrectomy (p < 0.001). Before donor nephrectomy, older age and higher BMI did not affect reserve capacity. After donor nephrectomy, the response of GFR to dopamine independently and negatively correlated with older age and higher BMI. Moreover, postdonation reserve capacity was absent in obese donors. The presence of overweight had more impact on loss of RC in younger donors. In conclusion, donor nephrectomy unmasked an age- and overweight-induced loss of reserve capacity. Younger donors with obesity should be carefully monitored.

Cystatin C Does Not Detect Acute Changes in Glomerular Filtration Rate in Early Diabetic Nephropathy

Background. The measurement of renal functional reserve (acute change in glomerular filtration rate [GFR] after protein load) allows the detection of sub-clinical renal dysfunction and has prognostic implications in diabetes. Our aim was to test cystatin C as an index of GFR and renal functional reserve. Methods. GFR was measured by CSinistrin at baseline and after protein load in 28 diabetic patients with serum creatinine <1.2 mg/dL. The CSinistrin was compared with cystatin C, serum creatinine, creatinine clearance, and Cockcroft-Gault formula. Results. Baseline CSinistrin ranged from 67–172 mL/min. Regression analysis showed an overall low relationship between CSinistrin and the indirect markers of GFR. The highest correlation with CSinistrin was obtained for cystatin C clearance (R2 = 0.58, r = 0.76, p < 0.001), the 1/serum cystatin C (R2 = 0.58, r = 0.76, p < 0.001), and serum cystatin C (R2 = 0.52, r = 0.72, p < 0.001). Renal functional reserve was preserved in 6 of 28 patients. There was no significant change in cystatin C in response to protein load. Conclusion. Wide variation in baseline GFR emphasizes the need for the early detection of renal dysfunction. Cystatin C correlated best with CSinistrin at baseline, but did not detect renal functional reserve.

Autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kiney disease is a hereditary systemic disorder, characterized by the developement of cysts, mainly in the kidney and liver, also with gastrointestinal and cardiovascular abnormalities. It affects 4 to 6 million people wordwide and accounts for end-stage renal disease in 7-10% of dialysis patients. The genetic penetrance is 100%, all affected individuals develop renal cysts until 70 years of age, and because of a great renal function reserve only about 50% of patients develop some degree of renal failure until the age of 60. Autosomal dominant polycystic kiney disease is a heterogeneous disorder, from a clinical as well as from a genetic point of view. There are at least three genes responsible for the disease: PKD-1 gene localized on chromosome 16p in the 16p13.3 segment which encodes Polycystin 1 protein similar to membrane receptor, PKD-2 gene localized on chromosome 4q in 4q13-23 segment which encodes Polycystin 2 protein wery similar to voltage L type Ca++ channel as well as Na+ channel and PKD-3 gene of unknown localization. Specific proteins participate in regulation od cell proliferation, apoptosis, secretion, polarity, cell-matrix interactions as cell-cell interactions and lead to the developement of cystic kidney disease. Renal manifestations of disease include structural (cyst development), functional (concentration alility falls), endocrine (renin erythropoietin) abnormalities and extra- renal manifestations. A routine diagnostic methods are good case-history about cystic kidney disease in family, ultrasonographic examination of kidneys and computerized tomography. In therapy of autosomal dominant polycystic kiney disease, low protein diets may help, treatment of arterial hypertension with ACE inhibitors and angiotensin II receptor blockers, the vasopressin V2 antagonists (VSR), rapamycin and long-acting somatostatin analogue may have some benefit.

Assessment and management of a patient with a renal transplant

Renal transplant recipients admitted on the medical take can be challenging for the clinician. Immunosuppressant medications, reduced renal functional reserve, increased vascular risk, and propensity to uncommon infections and malignancies all contribute to make management more complex than in other patients. This article reviews salient points in the management of such patients by the non-specialist.

Renal hemodynamic changes and renal functional reserve in children with type I diabetes mellitus

Increased glomerular filtration rate (GFR) has been implicated in the development of diabetic nephropathy. Large normal interindividual variations of GFR hamper the diagnosis of renal hemodynamic alterations. We examined renal functional reserve (RFR) in children with type 1 diabetes mellitus to assess whether hyperfiltration occurs. The renal hemodynamic response following dopamine infusion was examined in 51 normoalbuminuric diabetic children (7.7 +/- 3.6 years) with a mean duration of diabetes of 6.2 years and compared them with 34 controls. Mean baseline GFR in diabetic children did not differ from the control population (130.7 +/- 22.9 vs. 124.8 +/- 25 ml/min per 1.73 m(2)), whereas renal plasma flow was significantly lower (463.7 +/- 103.9 vs. 587.2 +/- 105 ml/min per 1.73 m(2), p < 0.001), and filtration fraction was increased (29 +/- 8 vs. 21 +/- 2%, p < 0.001), compared with controls. The mean RFR was lower (p < 0.001) than in control subjects (-0.77 +/- 23 vs. 21 +/- 8 ml/min per 1.73 m(2)). This study documents an increased filtration fraction and reduced or absent RFR in children with type 1 diabetes mellitus in the stage before apparent nephropathy. GFR values were within normal range. Although the reduced RFR and increased filtration fraction indicate the presence of hemodynamic changes, their relevance to the development of hyperfiltration and subsequent diabetic nephropathy remains unknown.

Renal Function Reserve in Chronic Obstructive Pulmonary Disease with Type II Respiratory Failure

Background and objective: increase in renal blood flow in response to certain stimuli such as dopamine infusion, oral protein load, and amino acid infusion. Reduced or absent renal functional reserve (RFR) is an early index of renal impairment. Our work studies the (RFR) in Chronic Obstructive Pulmonary Disease (COPD) patients with chronic compensated type II respiratory failure. Methods: Our study included 15 COPD patients with compensated type II respiratory failure and 5 normal controls. The patient group had mean Pa O2 56.5±6.4 and Pa CO2 56.5±3.2, while in normal controls the mean Pa O2 was 97.4 ± o.3 and Pa CO2 was 42.3 ± 1.2. Hypoxic patients (Pa O2 or=60mmHgandSaO2 >or=90%withoutriseofPaCO2within2 hours before and during the study. The pulsatility index (PI), an index of reno-vascular resistance (RVR), was measured non invasively by Doppler Ultrasonograghy at baseline and 20 minutes after infusion of dopamine in diuretic dose. Results: The baseline PI was nearly similar in the control group and in COPD patients (no significant difference), the PI fell significantly in the control group after dopamine infusion from 1.03 ± 0.14 to 0.83 ± 0.1(P< 0.05), but increased significantly in COPD patients from 1.02 ± 0.12 to1.18 ± 0.13 (P<0.05) after dopamine infusion. Conclusion: Renal functional reserve is impaired in hypercapnic COPD patients and this may be a factor in the development of edema frequently seen in these patients.

Renal Function Reserve in Chronic Obstructive Pulmonary Disease with Type II Respiratory Failure

increase in renal blood flow in response to certain stimuli such as dopamine infusion, oral protein load, and amino acid infusion. Reduced or absent renal functional reserve (RFR) is an early index of renal impairment. Our work studies the (RFR) in Chronic Obstructive Pulmonary Disease (COPD) patients with chronic compensated type II respiratory failure.

The role of renal function reserve estimation in children with hydronephrosis

Background: Glomerular filtration rate (GFR) is the most widely used indicator of kidney function although it does not invariably reflect the functional status after renal injury. The concept of renal function reserve (RFR) as the ability of the kidney to increase GFR following a protein load was introduced in 1980s. In hydronephrotic children, the acute hemodynamic response to intravenous protein load can cause changes in renal function that are different from changes in normal controls. Materials and Methods: RFR was evaluated in 21 children with hydronephrosis (group I - study group) and in 20 healthy children (group II - control group) by subtracting the baseline GFR from the stimulated GFR following an intravenous protein load. GFR was determined by double compartment-2 plasma sample method using 99m Tc DTPA (diethylenetriamine pentaacetic acid) radioisotope as the filtration agent. Results: The baseline GFR, stimulated GFR and RFR of hydronephrotic children (group I) was found to be significantly lower ( P = 0.01, P = 0.001 and P = 0.03 respectively) as compared with healthy normal children (group II). The stimulated GFR shows a strong correlation with the baseline GFR in both the groups, but the RFR shows a high inverse correlation to the baseline GFR in controls and a very low correlation in study group. Conclusion: RFR is preserved in children with hydronephrosis, but it is reduced in comparison to healthy children. However, its clinical utility to unmask the severity of hydronephrosis is limited by the various limiting factors.

Significance of the Renal Functional Reserve in Reflux Nephropathy: An Evaluation According to the Degree of Glomerular Damage

Objective. In the treatment of progressive reflux nephropathy (RN), the therapeutic benefit and prognosis of the renal function in RN patients appears to be influenced by the degree of renal functional reserve. We designed this study to determine the presence and characteristics of the renal functional reserve in RN patients. Materials and Methods. In the 35 RN patients with renal scars (19 males; mean age 16.1 years), an exogenous renal clearance test was performed to measure the glomerular filtration rate (GFR) and the effective renal plasma flow (ERPF). In the second half of this test, the renal functional reserve was estimated by measuring the GFR and ERPF during low-dose dopamine infusion. These measurements were then compared with the glomerular size, which had been previously determined by a renal biopsy. Results. Among the patients with a normal glomerular size (−2SD to +2SD), the GFR markedly increased after low-dose dopamine infusion (from 112.15 ± 52.51 to 182.07 ± 69.95mL/min, p < 0.0001), whereas an increase in ERPF was not significant. Among the patients with an enlarged glomerular size (+2SD to +4SD), the GFR and ERPF increased significantly over the baseline values (from 54.60 ± 32.90 to 114.00 ± 65.48 mL/min, p = 0.0076; from 281.01 ± 152.54 to 622.43 ± 392.73 mL/min, p = 0.0155, respectively). Among the patients with an extremely enlarged glomerular size (>+4SD), both the GFR and ERPF remained almost completely unchanged. Conclusion. The renal functional reserve was present even among progressive RN patients with a glomerular size ranging between +2SD and +4SD.

Renal functional reserve in obesity hypertension

The capacity to increase glomerular filtration rate in response to an acute oral protein load is known as the renal functional reserve; the loss of such capacity is used as a marker of hyperfiltration. This physiological response in obese hypertensives is not yet fully understood. We aimed to study the interdependent effects of obesity and hypertension on renal reserve, taking into account renal kallikrein and nitric oxide in the modulation of that parameter. Fourteen obese hypertensives (mean age, 50.5 +/- 0.9 years) and nine lean hypertensives (mean age, 50.6 +/- 2.7 years) were evaluated. Renal haemodynamics and the levels of serum nitric oxide and urinary kallikrein were assessed at baseline and after a protein load (1 g/kg of body weight). An increase in the following parameters was observed when comparing obese and lean hypertensives: basal glomerular filtration rate; renal plasma flow; and urinary kallikrein and nitric oxide levels (129.2 +/- 2.9 vs. 101.4 +/- 3.4 ml/min/1.73 m2; 587.5 +/- 18.2 vs. 502.8 +/- 16.7 ml/min/1.73 m2; 0.120 +/- 0.02 vs. 0.113 +/- 0.02 mU/ml; 23.2 +/- 0.8 vs. 19.5 +/- 1.2 mmol/ml, respectively). The renal reserve was lower in obese hypertensives when compared with that of lean hypertensives (4.1 +/- 0.5 vs. 11.8 +/- 0.8 ml/min, p < 0.005). After a protein load, contrasting with the lean group, inability to elevate the nitric oxide serum levels and a lower increase in urinary kallikrein were observed in the obese group. These data suggest that obese hypertensives lose renal reserve earlier in the evolution to renal dysfunction. This may be due to the defective modulation of renal vasodilatation mechanisms by renal kallikrein and nitric oxide production.

Renal artery stent revascularization with embolic protection in patients with ischemic nephropathy

A prospective analysis of renal artery stent revascularization with distal embolic protection in a high-risk patient population with ischemic nephropathy is presented. A total of 63 patients (median age 70.2 years, range 54-86 years) had significant atherosclerotic stenosis of 83 renal arteries documented on pre-procedural imaging. All patients had baseline chronic renal insufficiency with a documented deterioration in renal function in the 6 months before revascularization. The endovascular technique used in all patients involved primary passage of an embolic filter into the distal main renal artery followed by primary stent deployment with a balloon expandable stainless steel stent. The filter baskets were recaptured and contents submitted for pathological analysis. At 6 months post-intervention, 97% of patients demonstrated stabilization or improvement in renal function. Only 3% of patients had an inexorable decline in renal function, unchanged by the intervention. After a mean follow up of 16.0 months (6-27), 94% of patients demonstrated stabilization or improvement in renal function. One patient suffered an acute post-procedural deterioration in renal function. In total, 60% of the filter baskets contained embolic material. This study confirms the technical feasibility of renal artery stent deployment with adjuvant embolic protection. The excellent results for renal preservation at 6 months post-intervention also suggest that a distal embolic protection device may improve the impact of percutaneous renal revascularization on progressive deterioration in renal function. The postulated mechanism is through the prevention of atheromatous embolization and the embolic yield from the distal filters supports this hypothesis. Patients most likely to receive the greatest benefit are those with mild baseline chronic renal insufficiency and a recent decline in renal function.

Avaliação da perfusão renal pelo Power Doppler em pacientes transplantados renais

OBJETIVOS: O objetivo deste estudo é testar a aplicabilidade do estudo ultra-sonográfico com Power Doppler na identificação das alterações da perfusão dos rins transplantados e sua correlação com a reserva funcional renal e microalbuminúria antes e após a infusão de solução de aminoácidos intravenosos. MÉTODOS: Vinte e três pacientes transplantados renais foram avaliados pelo Power Doppler antes (fase basal), após 120 minutos (fase 1) e após 240 minutos (fase 2) da infusão intravenosa de aminoácidos. Concomitantemente, foram realizadas, nas três fases, dosagem de creatinina, avaliação do índice de filtração glomerular, da reserva funcional renal e de microalbuminúria. RESULTADOS: De acordo com os padrões de perfusão na fase basal pelo Power Doppler, descritos por Hoyer et al. em 1999, os pacientes foram divididos em três grupos: 12 pacientes com escore I, seis com escore II e cinco com escore III de perfusão renal. Nos enxertos renais com excelente perfusão renal (escore I), observou-se variação significativa das variáveis estudadas, tanto na fase 1 como na 2 (P CONCLUSÕES: Os achados sugerem que os transplantes com escore I de perfusão apresentam reserva funcional renal quando submetidos a estímulo com aminoácidos. No entanto, com a progressiva diminuição no grau de perfusão renal pelo Power Doppler, observa-se perda da capacidade dos rins transplantados em aumentar o índice de filtração glomerular como resposta a estímulos externos, com seqüente ausência de reserva funcional renal. A partir deste estudo, será possível criar novos horizontes para o entendimento da evolução dinâmica do processo de perda da função renal nos transplantados renais.

Effect of low environmental salinity on plasma composition and renal function of the Atlantic stingray, a euryhaline elasmobranch

Marine elasmobranchs maintain internal osmolality higher than their external environment, resulting in an osmotic gradient for branchial water uptake. This gradient is markedly increased in low-salinity habitats. The subsequent increase in water uptake presents a challenge to volume homeostasis. The Atlantic stingray is a marine elasmobranch that inhabits a remarkable range of environmental salinities. We hypothesized that the ability of these stingrays to regulate fluid volume in low-salinity environments is due primarily to a renal glomerular and tubular functional reserve. We tested this hypothesis by measuring renal excretory function after a rapid and sustained 50% reduction in the osmolality of the external medium. Atlantic stingrays were maintained in harbor water [control salinity (CS) approximately 850 mosmol/kgH(2)O] for 1 wk. Rays were then either transferred to diluted harbor water [low salinity (LS) approximately 440 mosmol/kgH(2)O] or maintained in CS for a further 24 h. Renal excretory function was markedly higher in the rays subjected to low salinity. Glomerular filtration rate was threefold higher and urine flow rate ninefold higher in the LS group. The clearance of solute-free water was greater, and solute-free water comprised a significantly larger proportion of the urine output for the stingrays transferred to dilute harbor water. We conclude that 1) the kidneys of Atlantic stingrays have a remarkable glomerular and tubular functional reserve, and 2) the marked increase in renal function attenuates the increase in fluid volume when these fish move into low-salinity habitats.

Measurement of Renal Functional Reserve in Children

Measurement of Renal Functional Reserve in Children

Measurement of Renal Functional Reserve in Children

No AccessJournal of UrologyUrological survey1 Jan 2006Measurement of Renal Functional Reserve in Children S. Hellerstein, M. Berenbom, P. Erwin, N. Wilson, and S. DiMaggio S. HellersteinS. Hellerstein More articles by this author , M. BerenbomM. Berenbom More articles by this author , P. ErwinP. Erwin More articles by this author , N. WilsonN. Wilson More articles by this author , and S. DiMaggioS. DiMaggio More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(05)00095-9AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail "Measurement of Renal Functional Reserve in Children." The Journal of Urology, 175(1), p. 313 Section of Nephrology, Children’s Mercy Hospital, University of Missouri School of Medicine at Kansas City, Kansas City, Missouri© 2006 by American Urological AssociationFiguresReferencesRelatedDetails Volume 175Issue 1January 2006Page: 313 Advertisement Copyright & Permissions© 2006 by American Urological AssociationMetricsAuthor Information S. Hellerstein More articles by this author M. Berenbom More articles by this author P. Erwin More articles by this author N. Wilson More articles by this author S. DiMaggio More articles by this author Expand All Advertisement Loading ...

Early detection of progressive renal dysfunction in patients with coronary artery disease

An association between renal hemodynamic dysfunction and coronary artery disease (CAD) has been documented in chronic renal failure; however, no information is available in CAD patients with normal glomerular filtration rate (GFR). This study was aimed at evaluating early abnormalities and outcome of renal function in CAD patients. In 15 nondiabetic patients with normal renal function and no significant stenoses in renal arteries, and having undergone coronary arteriography, we studied systemic and renal hemodynamics before and after a vasodilating stimulus induced by aminoacid (AA) infusion. A control group (C) consisted of 15 sex- and age-matched kidney donors. The statistical adequacy of the sample size was preliminarily verified. Renal clearances were repeated after two years. At baseline, GFR (mL/min/1.73 m2) averaged 81.4 +/- 3.8 in CAD and 83.7 +/- 1.4 in C (P= NS); RPF (mL/min/1.73 m2) was 297 +/- 22 in CAD and 456 +/- 15 in C (P < 0.0001); filtration fraction was higher in CAD (P < 0.001). Plasma renin activity was higher in CAD (P < 0.005). The number of coronary stenoses was inversely correlated with RPF but not with GFR. In CAD, at variance with C, AA did not induce any increment of GFR, while RPF increased without achieving the unstimulated value of C. Blood pressure was comparable in CAD and C at baseline and not modified by AA. After two years, a significant decrease in GFR (-14%, P < 0.001) and RPF (-15%, P < 0.001) occurred only in CAD, and in either group, the response to AA did not differ from that detected at baseline. In CAD patients with normal GFR, reduction in renal perfusion and absence of renal functional reserve likely represent early markers of progressive renal dysfunction.