RESUMEN
OBJECTIVE: Little is known about the effect of chronic kidney disease (CKD) on plaque morphology in cerebral vessels. We therefore analyzed plaque composition and metabolic and chemical parameters with regard to clinical outcome in patients with advanced carotid artery stenosis (>70%) and normal or impaired renal function. METHODS: Carotid endarterectomy plaques were collected from 114 patients, 51 with CKD and 63 without CKD (mean estimated glomerular filtration rate, 49 ± 9 vs 88 ± 14 mL/min), and analyzed by histology and immunohistochemistry. Serum levels of matrix metalloproteinases (MMP-1, -2, -3, -7, -8, and -9), calcium, phosphate, parathyroid hormone, fetuin-A, osteoprotegerin, and inflammatory factors, including fibrinogen, and high-sensitive C-reactive protein (hsCRP) were measured by appropriate enzyme-linked immunosorbent assay. RESULTS: Compared with patients without CKD, patients with CKD had significantly more early-stage (11.2% vs 2.8%, P = .002) and end-stage (7.4% vs 0.2%, P = .036) calcification, unstable (50.8% vs 20.4%, P = .001) and ruptured (53.1% vs 32.8%, P = .035) lesions, and a significantly lower amount of collagenous fibers (39.2% vs 54.6%, P = .001). Serum samples of CKD patients had significantly enhanced levels of fibrinogen (393 ± 88 vs 331 ± 60 mg/dL, P = .018), hsCRP (1.7 ± 2.9 vs 0.8 ± 0.9 mg/dL; P = .042), parathyroid hormone (47.3 ± 24.1 vs 32.8 ± 12.2 ng/L, P = .010), fetuin-A (0.21 ± 0.05 vs 0.18 ± 0.04 mg/mL, P = .039), and MMP-7 (13.0 ± 5.3 vs 8.3 ± 3.0 ng/mL; P < 0.001). The incidence of cerebrovascular events >6 months before carotid surgery was significantly increased in CKD patients (84.0% vs 26.2% P < .001). CONCLUSIONS: In patients with CKD and advanced carotid artery stenosis, morphologic changes in plaque composition may contribute to plaque vulnerability and consequently to the risk of cerebrovascular events. Furthermore, relevant serum markers of inflammation, vascular calcification, and vessel wall degradation might be an indication of stroke risk in CKD patients.
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Estenosis Carotídea/patología , Placa Aterosclerótica/patología , Insuficiencia Renal Crónica/complicaciones , Anciano , Anciano de 80 o más Años , Estenosis Carotídea/metabolismo , Estenosis Carotídea/cirugía , Estudios de Casos y Controles , Endarterectomía Carotidea , Femenino , Tasa de Filtración Glomerular , Humanos , Masculino , Placa Aterosclerótica/metabolismo , Placa Aterosclerótica/cirugía , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/patología , Factores de Riesgo , Resultado del TratamientoRESUMEN
BACKGROUND AND OBJECTIVES: To prevent diabetic nephropathy, knowledge about early renal impairment caused by a disturbed glucose homoeostasis is essential. The purpose of our study was to investigate haemodynamic changes of the kidney in subjects with impaired glucose tolerance (prediabetics, IGT) during experimental hyperglycaemia and the effect of angiotensin receptor blockade. DESIGN: In our prospective case control study, we measured renal haemodynamics in 13 non-albuminuric males with normal kidney function and IGT (diagnosed by an oral glucose tolerance test, OGTT) and in 13 matched controls with a normoglycemic response in the OGTT. Glomerular filtration rate (GFR) was assessed by determination of sinistrin clearance; renal plasma flow (RPF) by para-aminohippuric acid clearance. All measurements were performed at rest and during hyperglycaemic stress testing (clamp technique; target blood glucose approximately 170 mg dL(-1)). We examined renal effects of valsartan (4 weeks 160 mg day(-1)) at rest and during experimental hyperglycaemia. Metabolic (glycosylated haemoglobin, adiponectin) and inflammatory (high sensitive C-reactive protein) parameters were compared with and without valsartan in both groups. RESULTS: During experimental hyperglycaemia, GFR and RPF decreased significantly more in prediabetics compared with controls. Under valsartan, the hyperglycaemia induced decrease of GFR and RPF was blunted in part by valsartan. Hs-CRP and HbA1c were significantly higher in prediabetics when compared with controls and improved both under valsartan. Adiponectin was lower in prediabetics and increased significantly under valsartan. CONCLUSIONS: Hyperglycaemia induces impairments of renal haemodynamics as well as inflammatory and metabolic parameters in subjects with impaired glucose tolerance, which improve under valsartan.
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Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Glucemia/metabolismo , Hiperglucemia/fisiopatología , Receptor de Angiotensina Tipo 1/uso terapéutico , Circulación Renal/efectos de los fármacos , Tetrazoles/administración & dosificación , Valina/análogos & derivados , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Tasa de Filtración Glomerular , Prueba de Tolerancia a la Glucosa , Humanos , Hiperglucemia/inducido químicamente , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Resultado del Tratamiento , Valina/administración & dosificación , Valsartán , Adulto JovenAsunto(s)
Hematuria , Enfermedades Renales , Biopsia , Cistoscopía , Diagnóstico Diferencial , Femenino , Hematuria/clasificación , Hematuria/diagnóstico , Hematuria/diagnóstico por imagen , Hematuria/etiología , Humanos , Riñón/diagnóstico por imagen , Riñón/patología , Enfermedades Renales/complicaciones , Enfermedades Renales/diagnóstico , Enfermedades Renales/inmunología , Enfermedades Renales/patología , Enfermedades Renales/orina , Masculino , Persona de Mediana Edad , Nefritis/complicaciones , Nefritis/orina , Ultrasonografía , UrografíaRESUMEN
OBJECTIVE: The study investigated the effect of angiotensin receptor blockers (ARB) on glucose homeostasis and inflammatory parameters in patients with impaired glucose tolerance (IGT). RESEARCH DESIGN AND METHODS: We prospectively studied the insulin sensitivity index (ISI) and homeostasis model assessment-insulin resistance (HOMA-IR) in 13 obese males with IGT and in 13 matched control subjects with normal glucose tolerance (NGT) during hyperglycemic testing over 90 min. Adiponectin, retinol-binding protein 4 (RBP4), and high-sensitive C-reactive protein (hsCRP) were analyzed. Measurements were performed at baseline and after a 4-week treatment with 160 mg/day valsartan. The results of the IGT and NGT groups were compared. RESULTS: At baseline, HOMA-IR (IGT 4.1 +/- 3 vs. NGT 2.3 +/- 1.0, P < 0.01), hsCRP (IGT 3.9 +/- 1.9 vs. NGT 1.8 +/- 1 mg/l, P < 0.05), and RBP4 (IGT 27.1 +/- 2.1 vs. NGT 24.0 +/- 2.0 ng/ml, P < 0.05) were significantly higher, whereas ISI (IGT 1.5 +/- 0.9 vs. NGT 1.8 +/- 1.2, P < 0.05) and plasma adiponectin (IGT 3.2 +/- 0.9, NGT 5.2 +/- 2.4 microg/ml, P < 0.05) were significantly lower in the IGT group compared with the NGT group. Under ARB, there was an increase in both groups of adiponectin (IGT 4.1 +/- 1.9 microg/ml, NGT 6.3 +/- 2.9 microg/ml, P < 0.05) and an increase in ISI (IGT 1.5 +/- 0.9 to 2.3 +/- 1 microg/ml, NGT 1.8 +/- 1 to 2.5 +/- 2 microg/ml, P < 0.05). HOMA-IR (4.1 +/- 3 to 2.6 +/- 2; P < 0.01), hsCRP (3.9 +/- 1.9 to 1.8 +/- 1 mg/l, P < 0.05), and RBP4 (27.1 +/- 2.1 to 22.1 +/- 1.8 ng/ml, P < 0.01) decreased significantly in the IGT group. CONCLUSIONS: Insulin sensitivity and associated inflammatory factors improve under ARB in IGT patients.
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Intolerancia a la Glucosa/tratamiento farmacológico , Resistencia a la Insulina/fisiología , Sistema Renina-Angiotensina/efectos de los fármacos , Adiponectina/metabolismo , Adulto , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Proteína C-Reactiva/metabolismo , Intolerancia a la Glucosa/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Proteínas Plasmáticas de Unión al Retinol/metabolismo , Tetrazoles/uso terapéutico , Valina/análogos & derivados , Valina/uso terapéutico , ValsartánRESUMEN
Takayasu's arteritis (TA) is a rare inflammatory disease of the arteries that affects women of childbearing age. The optimal management for pregnant patients with this disease has not yet been defined. The course of disease seems to be neither affected nor worsened by pregnancy. We could not find reported maternal deaths directly related to pregnancy. However, many authors report maternal as well as fetal unfavorable events in the course of pregnancy. We describe a 25-year-old primigravida of Turkish-Greek origin who presented at 30 weeks of pregnancy with active TA. In the 37(th) week, intrauterine fetal death occurred. Our patient did not show high blood pressure or aortic inflammation. The course of her disease was stable. Whether a newly diagnosed TA during pregnancy should be regarded as an indication for premature delivery is discussed. An interdisciplinary collaboration of rheumatologists, nephrologists and obstetricians is necessary to improve maternal and fetal prognosis.
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Muerte Fetal/etiología , Complicaciones Cardiovasculares del Embarazo , Arteritis de Takayasu/complicaciones , Adulto , Femenino , Humanos , EmbarazoRESUMEN
BACKGROUND: High-protein diets are effective for weight reduction; however, little is known about the potential adverse renal effects of such diets. OBJECTIVE: The aim of our study was to compare the effect of a high-protein (HP) with a normal-protein (NP) diet on renal hemodynamics and selected clinical-chemical factors. DESIGN: We prospectively studied the effect of an HP diet (2.4 g x kg(-1) x d(-1)) with that of an NP diet (1.2 g x kg(-1) x d(-1)) on the glomerular filtration rate (assessed on the basis of sinistrin-an inulin analog-clearance) and renal plasma flow (para-aminohippuric acid clearance) by using the constant infusion technique. Filtration fraction and renal vascular resistance were calculated. Twenty-four healthy young men followed the 2 diet protocols for 7 d each in a crossover design. They were individually advised by a dietitian to achieve the planned protein intake by selecting normal foods under isocaloric conditions. Serum and urinary variables and renal hemodynamics were measured on day 7 of both diets. RESULTS: The glomerular filtration rate (NP: 125 +/- 5 mL/min; HP: 141 +/- 8 mL/min; P < 0.001) and filtration fraction (NP: 23 +/- 5%; HP: 28 +/- 5%; P < 0.05) increased significantly with the HP diet. Renal plasma flow was not significantly different between the HP (496 +/- 25 mL/min) and NP (507 +/- 18 mL/min) phases. Renal vascular resistance was not significantly different between the NP (94 +/- 6 mm Hg x mL(-1) x min(-1)) and HP (99 +/- 8 mm Hg x mL(-1) x min(-1)) phases. Blood urea nitrogen, serum uric acid, glucagon, natriuresis, urinary albumin, and urea excretion increased significantly with the HP diet. CONCLUSIONS: A short-term HP diet alters renal hemodynamics and renal excretion of uric acid, sodium, and albumin. More attention should be paid to the potential adverse renal effects of HP diets.
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Proteínas en la Dieta/administración & dosificación , Tasa de Filtración Glomerular , Hemodinámica , Adulto , Albuminuria/etiología , Presión Sanguínea , Estudios Cruzados , Humanos , Masculino , Estudios Prospectivos , Flujo Plasmático Renal , Ácido Úrico/orina , Resistencia VascularRESUMEN
Recurrent focal segmental glomerulosclerosis (FSGS) after renal transplantation with nephrotic syndrome is a serious problem with a high risk of graft loss. The therapeutic role of renin-angiotensin-system (RAS) blockers in recurrent FSGS is not clear. We present the safety and efficacy of an intensified triple RAS blockade with an ACE-inhibitor, an AT 1 receptor blocker and the direct renin inhibitor aliskiren in a 29-year-old renal transplant recipient with biopsy proven recurrence of FSGS and relapsing severe nephrotic syndrome. We subsequently used full dose ramipril, candesartan and aliskiren under a close monitoring of kidney function and electrolytes and examined the effect on proteinuria, clinical course and tolerability over 12 months. We found a significant and sustained antiproteinuric effect under triple RAS blockade. RAS blockade was generally well tolerated. This can offer a new therapeutic approach in selected hypertensive patients with recurrent FSGS.
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Amidas/uso terapéutico , Bloqueadores del Receptor Tipo 1 de Angiotensina II/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Bencimidazoles/uso terapéutico , Fumaratos/uso terapéutico , Glomeruloesclerosis Focal y Segmentaria/tratamiento farmacológico , Hipertensión Renal/tratamiento farmacológico , Trasplante de Riñón , Ramipril/uso terapéutico , Sistema Renina-Angiotensina/efectos de los fármacos , Renina/antagonistas & inhibidores , Tetrazoles/uso terapéutico , Adulto , Amidas/administración & dosificación , Bloqueadores del Receptor Tipo 1 de Angiotensina II/administración & dosificación , Inhibidores de la Enzima Convertidora de Angiotensina/administración & dosificación , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales de Origen Murino , Bencimidazoles/administración & dosificación , Compuestos de Bifenilo , Quimioterapia Combinada , Femenino , Fumaratos/administración & dosificación , Glomeruloesclerosis Focal y Segmentaria/complicaciones , Glomeruloesclerosis Focal y Segmentaria/patología , Glomeruloesclerosis Focal y Segmentaria/cirugía , Humanos , Hipertensión Renal/etiología , Síndrome Nefrótico/tratamiento farmacológico , Síndrome Nefrótico/etiología , Intercambio Plasmático , Proteinuria/tratamiento farmacológico , Proteinuria/etiología , Ramipril/administración & dosificación , Recurrencia , Rituximab , Tetrazoles/administración & dosificaciónRESUMEN
BACKGROUND AND PURPOSE: Experimental studies suggested neurovascular compression of the brain stem as a cause of hypertension. The aim of our prospective study was to investigate the effect of microvascular decompression in patients with severe hypertension with neurovascular compression on blood pressure and central sympathetic nerve activity in the long-term. METHODS: Fourteen patients (4 males; mean age, 46+/-8 years) with essential hypertension underwent microvascular decompression of the brain stem. Vasoconstrictor muscle sympathetic nerve activity (recorded by microneurography: burst frequency, bursts/min) and blood pressure (24-hour profiles) were investigated before surgery and 7 days, 3 months, and every 6 months postoperatively. RESULTS: Muscle sympathetic nerve activity was preoperatively elevated and decreased significantly postoperatively (35+/-13 bursts/min vs 20+/-9 bursts/min; P<0.01). Sympathetic activity remained reduced 3 months (19+/-8 bursts/min; P<0.01), 6 months (19+/-7 bursts/min; P<0.01), and 12 months (23+/-9 bursts/min; P<0.01) postoperatively. However, in the long-term, sympathetic nerve activity increased again (18 months after surgery: 28+/-10 bursts, not significant; 24 months postoperatively: 34+/-12 bursts/min, not significant). Systolic and diastolic blood pressure decreased from 162+/-6/98+/-5 mm Hg preoperatively to 133+/-6/85+/-4 mm Hg (7 days postoperatively; P<0.01); 136+/-5/86+/-4 mm Hg (3 months postoperatively; P<0.01); 132+/-4/85+/-4 mm Hg (6 months postoperatively; P<0.01); 132+/-3/85+/-5 mm Hg (12 months postoperatively; P<0.01); 132+/-5/84+/-5 mm Hg; P<0.01). Twenty-four months after microvascular decompression, blood pressure increased again up to 158+/-7/96+/-6 mm Hg, corresponding to the sympathetic nerve activity course. CONCLUSIONS: Sympathetic nerve activity and blood pressure are temporary reduced by microvascular decompression in patients with severe hypertension with neurovascular compression. The data are a hint for sympathetic overactivity as a pathomechanism in this subgroup of patients.
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Enfermedades del Sistema Nervioso Autónomo/fisiopatología , Enfermedades del Sistema Nervioso Autónomo/cirugía , Descompresión Quirúrgica/estadística & datos numéricos , Hipertensión/fisiopatología , Hipertensión/cirugía , Bulbo Raquídeo/fisiopatología , Adulto , Enfermedades del Sistema Nervioso Autónomo/etiología , Vías Autónomas/fisiopatología , Arteria Basilar/inervación , Arteria Basilar/fisiopatología , Arteria Basilar/cirugía , Presión Sanguínea/fisiología , Descompresión Quirúrgica/métodos , Femenino , Humanos , Hipertensión/etiología , Masculino , Bulbo Raquídeo/irrigación sanguínea , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos/métodos , Procedimientos Neuroquirúrgicos/estadística & datos numéricos , Estudios Prospectivos , Recurrencia , Formación Reticular/irrigación sanguínea , Formación Reticular/fisiopatología , Fibras Simpáticas Posganglionares/fisiopatología , Resultado del Tratamiento , Procedimientos Quirúrgicos Vasculares/métodos , Procedimientos Quirúrgicos Vasculares/estadística & datos numéricos , Vasoconstricción/fisiologíaRESUMEN
BACKGROUND: Mortality of severe sepsis and septic shock is unacceptably high. Adsorptive removal of endotoxin may interrupt the inflammatory cascade triggered by lipopolysaccharide. METHODS: Prospective feasibility study with plasma separation and adsorption (PSA) treatment using a novel arginine-coated adsorber column was performed in a tertiary care gastroenterological intensive care unit. RESULTS: 10 patients with severe sepsis/septic shock (median APACHE II score: 27, hospital mortality 40%) were treated with PSA on 5 consecutive days. There were no serious adverse events. No patient died during the treatment period. During treatment sessions, mean arterial pressure and cardiac power index increased while vasopressors could be reduced. Advanced oxidation protein products and in vitro pro- apoptotic activity of plasma decreased. We could not demonstrate any changes in endotoxin levels. CONCLUSIONS: PSA resulted in a reduction of indicators of oxidative stress and pro-apoptotic activity of the plasma and an improvement in hemodynamic parameters, suggesting increased myocardial contractility and reduced septic vasodilation.
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Arginina/uso terapéutico , Hemodinámica , Hemoperfusión/métodos , Lipopolisacáridos/sangre , Estrés Oxidativo , Sepsis/terapia , Adulto , Anciano , Apoptosis , Presión Sanguínea , Gasto Cardíaco , Estudios de Factibilidad , Femenino , Hemoperfusión/instrumentación , Mortalidad Hospitalaria , Humanos , Masculino , Persona de Mediana Edad , Sepsis/mortalidad , Choque Séptico , VasoconstricciónRESUMEN
In an unusual course of Wegener's granulomatosis (WG), a 71-year-old woman presented a 3-week history of unilateral painful parotid swelling unresponsive to antiphlogistic and antibiotic treatment. Following lateral parotidectomy with unspecific inflammatory histopathological findings, the patient developed disturbance of wound healing and high recurrent fever. Control chest X-ray showed several pulmonary round lesions. Immunologic testing for antinuclear cytoplasmatic antibodies (ANCA) was positive and CT navigated puncture revealed pronounced necrotic vasculitis of small arteries and veins. Consequently, systemic WG was diagnosed and specific immunosuppressive therapy was started. Long-term follow-up of 6 months showed a decline in the ANCA course, full remission of the presented symptoms and prevention of renal manifestations. Isolated inflammatory parotid enlargement can be the initial symptom of systemic WG and should be considered as differential diagnosis, especially when nondiagnostic histopathological results are obtained. Early testing for c-ANCA supplies valuable information and therefore should be prompted when additional symptoms occur. Once diagnosed as WG, appropriate therapy is able to prevent progression to severe clinical courses.
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Granulomatosis con Poliangitis/diagnóstico , Parotiditis/complicaciones , Anciano , Femenino , Granulomatosis con Poliangitis/complicaciones , Granulomatosis con Poliangitis/patología , Humanos , Glándula Parótida/patologíaRESUMEN
BACKGROUND: Renal anemia is an important determinant for left ventricular hypertrophy in dialysis patients and an independent prognosis parameter for the cardiovascular survival in dialysis patients. In addition, an autonomic dysfunction is associated with the uremic state and influences the cardiovascular risk in patients with end-stage renal disease (ESRD). METHODS: We investigated in this prospective longitudinal study the effect of hemoglobin normalization by a chronic treatment with recombinant human erythropoietin (rhEPO) on cardiovascular prognosis parameters in 23 patients on chronic hemodialysis with renal anemia (hemoglobin concentration < or =10.5 g/dL) and echocardiographically proven left ventricular hypertrophy. We studied muscle sympathetic nerve activity measured by microneurography; cardiopulmonary baroreflex activity by lower-body negative pressure (LBNP-) testing; left ventricular structure and mass index (LVMI) by echocardiography; blood pressure by 24-hour readings; peripheral blood flow and vascular resistance by plethysmography before (U1) and after 7 months of chronic rhEPO treatment (U2). RESULTS: In the anemic state, mean (+/- SD) muscle sympathetic nerve activity in ESRD was elevated (U1 rest, 34 +/- 13 bursts per minute) and cardiopulmonary baroreflex response during LBNP markedly lacking (U1 -15 mm Hg, 34 +/- 13 bursts per minute) reflecting a severely impaired autonomic function. Normalization of the hemoglobin concentration by chronic rhEPO treatment (U1, 10.5 +/- 0.9 g/dL versus U2, 13.4 +/- 3.1 g/dL, P <0.001) did not influence sympathetic nerve activity (U2, 34 +/- 15 bursts per minute, NS) and cardiopulmonary baroreflex sensitivity did not change (U2 -15 mm Hg, 37 +/- 16 bursts per minute, NS). LVMI decreased significantly after chronic treatment with rhEPO (U1, 134 +/- 26 g/m2 versus U2, 97 +/- 25 g/m2, P < 0.001) and left ventricular geometry developed from an asymmetric to a symmetric configuration (U1, relative wall thickness 0.58 versus U2, 0.43, P < 0.001). Under treatment with rhEPO, 24-hour systolic and diastolic blood pressure did not increase (systolic U1, 132 +/- 4 mm Hg versus U2, 128 +/- 3 mm Hg, NS, and diastolic U1, 76 +/- 2 mm Hg versus U2, 73 +/- 2 mm Hg, NS). Peripheral blood flow (U1, 6.1 +/- 3.3 mL/100 mL/min versus U2, 6.2 +/- 0.6 mL/100 mL/min, NS) as well as forearm vascular resistance (U1, 15.7 +/- 3.3 mm Hg/mL/100 mL versus U2, 14.9 +/- 3.1 mm Hg/mL/100 mL, NS) did not change by chronic rhEPO treatment. CONCLUSION: Normalization of hemoglobin by chronic rhEPO treatment in dialysis patients has beneficial cardiovascular effects with regression of left ventricular hypertrophy and improvement of left ventricular geometry. However, a reduction of sympathetic overactivity or a resetting of baroreceptor sensitivity by a rhEPO treatment in dialysis patients in the medium-term could not be demonstrated. The reason for this may be the complex and multifactorial pathomechanism of autonomic dysfunction and cardiovascular disease in ESRD.
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Anemia/tratamiento farmacológico , Eritropoyetina/administración & dosificación , Hipertrofia Ventricular Izquierda/tratamiento farmacológico , Fallo Renal Crónico/complicaciones , Diálisis Renal , Adulto , Anciano , Anemia/etiología , Barorreflejo , Presión Sanguínea , Ecocardiografía , Femenino , Humanos , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Fallo Renal Crónico/terapia , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Proteínas Recombinantes , Flujo Sanguíneo RegionalRESUMEN
BACKGROUND: To elucidate the effect of the angiotensin type 1 (AT1) receptor antagonist (AT1RA) eprosartan (E) on renal hemodynamics in normotensive and borderline hypertensive subjects, we investigated the hormonal and renal hemodynamic responses during cardiopulmonary stress testing. METHODS: In a prospective, double-blind, randomized, placebo-controlled crossover study, the effects of E on renal plasma flow (RPF), renal blood flow (RBF), glomerular filtration rate (GFR), and the concentration of angiotensin II (Ang II) levels were measured with the subjects at rest and during perturbation of cardiopulmonary baroreceptors using lower body negative pressure (LBNP). Ten normotensive male subjects (NT) versus 14 males with mild hypertension (HT), matched for age and body mass index, who were all free of any medication, were randomly assigned to receive placebo or E 600 mg/day PO for seven days (intake phase 1). After a washout period of four weeks the subjects started the intake of the other substance for seven days in a crossover manner (intake phase 2). The measurements were taken on day 7 of both intake phases. RESULTS: During the LBNP test, RPF and RBF were reduced significantly in all subjects; GFR, however, decreased significantly during cardiopulmonary stress testing in the subjects taking the placebo (P < 0.05) and remained unchanged in those under treatment with AT1RA. Ang II levels increased significantly during cardiopulmonary stress test only in the subjects with hypertension who were on placebo, whereas the Ang II levels did not change in normotensive subjects or those treated with the AT1RA. CONCLUSIONS: The data confirm that with cardiovascular stress simulating orthostasis or volume depletion, subjects with AT1RA can maintain their GFR level, suggesting that AT1RA potentially is renoprotective. Additionally, the neurohumoral system is activated after cardiovascular stress in subjects even at an early stage of hypertension.
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Acrilatos/farmacología , Antagonistas de Receptores de Angiotensina , Hipertensión/fisiopatología , Imidazoles/farmacología , Presión Negativa de la Región Corporal Inferior , Circulación Renal/efectos de los fármacos , Tiofenos , Adulto , Angiotensina II/sangre , Presión Sanguínea/efectos de los fármacos , Estudios Cruzados , Método Doble Ciego , Glándulas Endocrinas/efectos de los fármacos , Glándulas Endocrinas/fisiología , Tasa de Filtración Glomerular/efectos de los fármacos , Hemodinámica/efectos de los fármacos , Humanos , Hipertensión/sangre , Masculino , Índice de Severidad de la EnfermedadAsunto(s)
Diálisis Peritoneal Ambulatoria Continua/efectos adversos , Enfermedades Renales Poliquísticas/diagnóstico , Enfermedades Renales Poliquísticas/etiología , Riñón Poliquístico Autosómico Dominante/diagnóstico , Adulto , Diagnóstico Diferencial , Glomerulonefritis por IGA/complicaciones , Humanos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Masculino , Enfermedades Renales Poliquísticas/patologíaRESUMEN
Recent data suggest a causal relationship between essential hypertension and neurovascular compression (NVC) at the rostral ventrolateral medulla. An increase of central sympathetic outflow might be an underlying pathomechanism. The sympathetic nerve activity to muscle was recorded in 21 patients with hypertension with NVC (NVC+ group) and in 12 patients with hypertension without NVC (NVC- group). Heart rate variability, respiratory activity, BP, and central venous pressure at rest and during unloading of cardiopulmonary baroreceptors with lower-body negative pressure and during a cold pressor test were also measured. Resting sympathetic nerve activity to muscle was twice as high in the NVC+ group compared with the NVC- group (34 +/- 22 versus 18 +/- 6 bursts/min; P < 0.05). Resting heart rate (P = 0.06) and low- to high-frequency power ratio values (P = NS) (as indicators of cardiac sympathovagal balance) tended to be augmented as well in the NVC+ group. The sympathetic nerve activity to muscle response to the cold pressor test was increased in the NVC+ group versus the NVC- group (+15 +/- 11 versus 6 +/- 12 bursts/min; P = 0.05), but hemodynamic and sympathetic nerve responses to lower-body negative pressure did not differ between the two groups. It is concluded that NVC of the rostral ventrolateral medulla in patients with essential hypertension is accompanied by increased central sympathetic outflow. Therefore, these data support the hypothesis described in the literature: in a subgroup of patients, essential hypertension might be causally related to NVC of the rostral ventrolateral medulla, at least in part, via an increase in central sympathetic outflow.