Showing papers by "Giuseppe Maschio published in 1990"

Renal functional reserve in patients with essential hypertension: effect of inhibition of the renin--angiotensin system.

Abstract: 1 Urinary albumin excretion and the effect of an acute oral protein load (a meat meal) on glomerular filtration rate ('renal functional reserve') were evaluated in 15 essential hypertensive patients with preserved renal function and compared with 12 normal subjects 2 Seven patients had microalbuminuria (greater than 30 mg/day) that was not correlated with blood pressure values 3 After an oral protein load, an average increase of 20% in glomerular filtration rate (from 91 +/- 19 to 110 +/- 27 ml min-1 173 m-2 was found in the hypertensive patients This change was not statistically different from that observed in normal controls (from 102 +/- 7 to 124 +/- 9 ml min-1 173 m-2) The glomerular response in hypertensive patients was independent of age, duration of hypertension, blood pressure, plasma renin activity, urinary albumin excretion and retinal vascular alterations 4 All patients were re-evaluated after 6 weeks treatment with a new orally active angiotensin-converting enzyme inhibitor, benazepril Systolic, diastolic and mean blood pressures were lowered in all the patients, but the drug did not affect the glomerular response to acute protein ingestion or the magnitude of urinary albumin excretion 5 The findings of a normal 'renal functional reserve' and a lack of change in both urinary albumin excretion and the glomerular response after angiotensin-converting enzyme inhibition cast doubt on the existence of increased intraglomerular pressure in hypertensive patients

Systemic and renal effects of a new angiotensin converting enzyme inhibitor, benazepril, in essential hypertension.

Abstract: Seventeen essential hypertensive patients with normal renal function were treated with a new non-sulphydryl orally active angiotensin converting enzyme (ACE) inhibitor, benazepril, 10 mg given once or twice daily, according to diastolic blood pressure levels, for 6 weeks. In all patients, changes in blood pressure, systemic and renal hemodynamics, plasma renin activity and urinary aldosterone and albumin excretions were assessed at the end of a 2-week placebo run-in period and at the end of the study. Benazepril monotherapy controlled blood pressure well. No changes in cardiac output, heart rate or stroke volume were observed, while peripheral vascular resistance was significantly decreased (-11%, P less than 0.05). Plasma volume was unaltered. The glomerular filtration rate was stable, but effective renal plasma flow was increased because of the marked reduction in renal vascular resistance (-35%) and, therefore, the filtration fraction was decreased. Urinary albumin excretion remained unchanged. A significant increase in plasma renin activity (P less than 0.001) and a decrease in urinary aldosterone excretion were seen. No side effects were observed during the treatment period. In conclusion, our results suggest that benazepril alone is an effective antihypertensive agent in patients with essential hypertension. The blood pressure lowering effect is due mainly to systemic vasodilation and is observed up to 24 h after administration of the drug. The vasodilation appears to be more consistent in the renal than in the systemic circulation.

Modification of serum and membrane lipid composition induced by diet in patients with chronic renal failure.

Abstract: Disorders of lipid metabolism during chronic renal failure (CRF) play a crucial role in the pathogenesis of early cardiovascular complication of this syndrome. In addition, some experimental evidence suggests that hyperlipidemia may accelerate progression of renal disease. We have studied 65 patients with CRF (S-creatinine 1.5-9.0 mg/dl), 52.3% of whom were hypertensive. Patients were divided in 2 groups matched for age, sex and degree of renal failure: group 1 was kept for 36 +/- 8 months on a free diet; group 2 was kept for 39 +/- 6 months on a low-protein diet with an elevated polyunsaturated/saturated fatty acid (PUFA/SFA) ratio. We found significantly higher levels of triglycerides (TG) and lower levels of esterified cholesterol in high density lipoprotein (HDL-C) in group 1 than in group 2. Patients on the diet had a lower percentage of membrane SFA and a higher percentage of PUFA than patients on free diet. Only in group 1 a direct correlation between cholesterol/phospholipid (Chol/P) ratio and age was observed; in group 2, a negative correlation between levels of PUFA and TG and between linoleic/oleic (Lin/Ol) ratio and serum Chol was shown. S-creatinine levels were directly correlated with Chol/P ratio in group 1 and indirectly with Lin/Ol ratio and PUFA in group 2. These data show that a low-protein diet, containing an elevated PUFA/SFA ratio, is able to counteract lipid abnormalities in patients with CRF and the normalization of this pattern is associated with significant improvement of membrane lipid composition and, presumably, of "functional" activity of cell membranes with a better control of supposed "renal lipoprotein toxicity".