Prevalence of micro- and macroalbuminuria and their relationship with other cardiovascular risk factors in essential hypertension.

A cohort of 227 untreated essential hypertensive patients from north-western Italy was studied in order to evaluate the prevalence of micro- and macroalbuminuria and their relationship with other cardiovascular risk factors. Albuminuria was evaluated as the albumin to creatinine ratio (Alb/Cr) in three non-consecutive first morning samples. The prevalence of microalbuminuria and macroalbuminuria was 10% and 2.

[Microalbuminuria, hypertension, and cardiovascular risk].

A growing interest in the study of microalbuminuria (Mi) in essential hypertension (EH) has recently emerged. While clinical proteinuria is found with a low frequence (between 4 and 16%) in patients with EH, a variable but generally higher prevalence (10-40%) of Mi has been reported, even in the absence of diabetes and nephropathy. Mi is defined as an abnormal urinary excretion of albumin (20-200 micrograms/min), undetectable by conventional tests.

Ultrasonographic imaging and Doppler analysis of renal changes in non-insulin-dependent diabetes mellitus.

Rationale And Objectives: We used ultrasonographic imaging and Doppler analysis to assess renal changes in patients with non-insulin-dependent diabetes mellitus (NIDDM) and normal renal function, as established by normal serum creatinine levels and the absence of macroalbuminuria.

Methods: Renal parenchymal echogenicity, renal volume, and resistive index (RI) were blindly evaluated for 85 NIDDM patients and 42 age-matched control subjects (C). Results were analyzed and correlated with the following clinical parameters: patient age, duration of diabetes, blood pressure, blood glucose and cholesterol levels, and the presence of microalbuminuria.

Insulin activation of red blood cell Na+/H+ exchange decreases the affinity of sodium sites.

We have previously reported increased activity of Na+/H+ and Na+/Li+ exchanges in red blood cells (RBC) of patients with hypertension and diabetic nephropathy. The presence in human red blood cells (RBC) of insulin receptors has led us to examine the effects of this hormone on the kinetic parameters of Na+/H+ exchange as a first approach to define its mechanism of action. The antiporter activity was measured as net Na+ influx driven by an outward H+ gradient in acid-loaded, Na-depleted RBCs preincubated with or without (w/wo) insulin (0 to 100 microU/ml) for different time periods.

Regional cerebral blood flow in chronic hypertension. A correlative study.

Background And Purpose: Cerebral hypoperfusion has occasionally been reported during essential hypertension. We explored regional cerebral blood flow in a large series of neurologically asymptomatic hypertensive patients to determine relations among cerebral blood flow, concomitant main vascular risk factors, and the most common signs of end-organ damage.

Methods: Regional cerebral blood flow was measured by the 133Xe inhalation method in 101 hypertensive patients without clinically apparent central nervous system involvement, including 39 mild to moderate untreated and 62 mild to severe treated patients.

Cardiac diastolic abnormalities and atrial natriuretic factor in essential hypertension.

Cardiac function and plasma levels of atrial natriuretic factor (ANF) were studied in a group of 38 patients with untreated essential hypertension and in a group of 31 well matched normotensive controls. ANF was slightly but significantly higher in hypertensives and was directly correlated with mean arterial pressure and inversely with plasma renin activity (PRA). Hypertensives showed normal systolic function and higher cardiac mass compared to controls.

Effects of a protein meal on blood amino acid profile in patients with chronic renal failure.

Arterial whole blood levels of amino acids were determined in patients with chronic renal failure and in healthy subjects before and after 270 min after the ingestion of a grilled beefsteak (4 g/kg). In patients, total nonessential amino acids increased significantly more (+46%) than in controls owing to an exaggerated rise of serine, glutamine, proline, glycine, cyst(e)ine and alanine. Total essential amino acids increased as much as in controls; however, threonine, histidine and phenylalanine showed greater increases, while tryptophan had a smaller increment.

Red cell sodium-proton exchange is increased in Dahl salt-sensitive hypertensive rats.

To investigate the relationship between red blood cell Na+/H+ exchange (EXC) and genetic factors in hypertension, we studied the maximal rate of the antiporter (mmol/liter cell x hr; flux units = FU) in three strains of genetically hypertensive rats. Salt-resistant Dahl rats (DR) were normotensive under low (0.02%) and high (8%) NaCl diets, while salt-sensitive Dahl rats (DS) became markedly hypertensive after four weeks on the high-NaCl diet.

Renal ammoniagenesis in humans with chronic potassium depletion.

Renal ammonia production and distribution and ammonia precursor utilization were evaluated in eight patients with chronic potassium depletion (CPD) and aldosterone-producing adenoma and in 20 controls. In CPD, urinary ammonia excretion and ammonia added to renal venous blood were about twofold higher than in controls; thus, total ammonia production was significantly augmented (88.0 +/- 10.

The calpastatin defect in hypertension is possibly due to a specific degradation by calpain.

Calpastatin activity, significantly reduced in erythrocytes of patients affected by essential hypertension, is restored to normal values by appropriate therapeutical treatments in a time-dependent fashion and in parallel with the decline in blood pressure. Evidence is also presented indicating that red cell calpastatin is degraded in human and rat red cells by homologous calpain, and that the rate of degradation is approx. 5-times higher in rat erythrocytes.

[Captopril-induced changes in renal flow: evaluation using Doppler echography].

It is well known that angiotensin antagonists cause increase of renal blood flow. We have examined, using duplex Doppler sonography, the changes of renal blood flow velocity induced by oral administration of 50 mg. of Captopril.

Renal metabolism of amino acids in early insulin-dependent diabetes mellitus.

Renal metabolism of amino acids (AAs) was evaluated in 5 patients with early IDDM, and in 7 controls (C) in the basal state for 80 minutes after the ingestion of an AA mixture simulating an animal protein meal. Insulin was withdrawn 20 hours before the study. Renal metabolism of AAs was evaluated by the arterial-venous difference technique.

Changes in blood pressure, plasma triglyceride and aldosterone concentration, and red cell cation concentration in patients with hyperinsulinemia.

Blood pressure, plasma concentration of triglyceride, aldosterone, renin activity (PRA), and atrial naturietic peptide (ANP), and red blood cell, urine, and plasma sodium and potassium concentration were determined in 24 healthy individuals divided into two groups defined as being either hyperinsulinemic or normoinsulinemic. The results demonstrated that the hyperinsulinemic group had significantly higher values for both systolic (P less than .01) and diastolic (P less than .

Long-term minoxidil treatment in refractory hypertension and renal failure.

Twenty-two patients with severe or accelerated hypertension refractory to conventional hypotensive therapy have been treated with minoxidil for an extended period. Patients were divided in three groups according to different degrees of renal function or the presence of accelerated hypertension. In the first group (8 patients with normal or slightly decreased renal function) BP fell from 197 +/- 11/118 +/- 3 before minoxidil therapy to 157 +/- 7/98 +/- 2 after six months (p less than 0.

Acute renal failure due to acute bilateral renal artery thrombosis: successful surgical revascularization after prolonged anuria.

Acute bilateral renal artery thrombosis is a rare but surgically correctable cause of acute renal failure. A middle-aged woman with acute renal failure and anuria due to atherosclerotic occlusion of the abdominal aorta and both renal arteries was surgically treated 42 days after the onset of anuria. Revascularization resulted in the reversal of renal failure and complete recovery of renal function in spite of prolonged anuria.

Multiple venous sampling for catecholamine assay in the diagnosis of malignant pheochromocytoma.

Malignant pheochromocytoma is a rare cause of hypertension and still has a high mortality rate. The most accurate way to localize a malignant pheochromocytoma is by a combination of scans, both CT and scintigraphy. Selective sampling of venous blood from multiple sites for plasma catecholamine levels is a safe and reliable technique and may be used successfully in some patients.

Characterization of the calpastatin defect in erythrocytes from patients with essential hypertension.

In erythrocytes of patients with essential hypertension the level of calpastatin activity was found to be significantly lower than in red cells of normotensive subjects (1). We now demonstrate, by Western blot analysis, that the decreased inhibitory activity is due to a corresponding decrease in the amount of the inhibitor protein. This is also supported by the observation that calpastatins isolated and purified from erythrocytes of normotensive and hypertensive patients, have identical specific activity.