Showing papers by "Luis M. Ruilope published in 1992"

Additive antiproteinuric effect of converting enzyme inhibition and a low protein intake.

Abstract: The hypothesis that converting enzyme inhibition and a protein-restricted diet could have additive antiproteinuric effects has been tested. A group of 17 patients with proteinuria in excess of 3 g/24 h per 1.73 m2 of body surface area were submitted to a 3-wk period of study, after a 4-wk wash-out period during which protein intake was 1.0 g/kg per day and in the absence of any medication. During the first and second weeks of the study, protein intake was lowered to 0.3 g/kg per day, and in the third week, it returned to 1.0 g/kg per day. Enalapril (20 mg daily) was administered during the second and third weeks of the study. Initially and at the end of each week thereafter, we determined blood pressure, GFR (inulin clearance), RPF (para-aminohippurate clearance), plasma sodium and potassium, PRA and aldosterone, and the 24-h urine excretion of sodium potassium, protein, and urea. The low protein intake during the first week induced a significant fall of proteinuria (P < 0.01), GFR (P < 0.01), and RPF (P < 0.01) in the absence of changes in filtration fraction. The addition of enalapril induced a further decrease of proteinuria (P < 0.01) and a fall in filtration fraction (P < 0.05), whereas plasma potassium, PRA, GFR, and RPF values increased (P < 0.01). The rise in protein intake during the last week of the study induced a significant rise in proteinuria, GFR, and RPF (P < 0.01), although the first of these parameters attained values significantly lower (P < 0.05) than those observed initially.(ABSTRACT TRUNCATED AT 250 WORDS)

Renal consequences of arterial hypertension.

Abstract: Aim To seek ways of improving the prognosis for renal function in the presence of arterial hypertension. Background Nephrosclerosis is a term used to define the renal damage induced by arterial hypertension. The renal vasculature can participate in the genesis of essential hypertension and can suffer the consequences of elevated blood pressure. There is no doubt that antihypertensive therapy has dramatically improved the prognosis for renal function in the presence of arterial hypertension. Results of literature review There appears to be a need for a further improvement in the prognosis for renal hypertension. At present, the prevalence of nephrosclerosis as a cause of terminal renal failure may be increasing and a progressive fall in renal function in treated hypertensive patients compared to normotensives has been described. Conclusions It is not yet clear whether improvements in renal hypertension depend merely on the effectiveness of antihypertensive therapy in reducing arterial blood pressure or whether it will be necessary to improve the metabolic disturbances that accompany hypertension or the renal hemodynamic effects of different drugs before the prognosis for nephrosclerosis can be improved.

Sodium Intake Does Not Influence the Effect of Verapamil in Hypertensive Patients with Mild Renal Insufficiency

Abstract: Information is limited regarding the efficacy of antihypertensive drugs in patients with hypertension associated with renal insufficiency. To address this question, a group of 14 outpatients with essential hypertension and mild renal insufficiency received slow release verapamil 240 mg/day for 14 days after a 4-week washout period. Patients were randomly assigned to a low (4 g/day) or high (11 g/day) salt diet, and crossed over to the alternative diet after 7 days. 24-Hour blood pressure monitoring was performed at the end of the washout period and after 7 and 14 days during verapamil treatment. Verapamil induced a significant fall in mean 24-hour blood pressure that was similar for patients on both diets (p < 0.01). As expected, natriuresis increased significantly during high sodium intake (p < 0.01), and bodyweight fell significantly when sodium intake was reduced (p < 0.05). Meanwhile, serum creatinine and creatinine clearance remained stable. These results indicate that the antihypertensive effect of verapamil is independent of sodium intake even in the presence of mild renal insufficiency.

Abnormalities of renal function in essential hypertension with increased circulating levels of insulin-like growth factor I.

Abstract: An increase in glomerular filtration rate and in tubular Na+ reabsorption from the parenteral administration of insulin-like growth factor I (IGF-I) have been reported in human subjects. To evaluate whether glomerular hyperfiltration and Na+ hyper-reabsorption present in some essential hypertensives are associated to an excess of IGF-I, the plasma levels of this factor and several parameters of renal function were studied in 30 non-treated essential hypertensives and in 30 normotensive controls. IGF-I levels were higher in hypertensive as compared to controls. With the 95% (upper) limit of the normotensive population as a cut-off point, a subgroup of six hypertensives had an abnormally high IGF-I level. Mean blood pressure was slightly lower in these six patients (112 +/- 7 mmHg) than in the remaining patients (120 +/- 2 mmHg). As compared to normotensives and hypertensives with normal IGF-I levels, patients with increased IGF-I levels were characterized by lower (P < 0.01) fractional Na+ excretion and higher (P < 0.05) creatinine clearance. The analysis of the relation of plasma renin activity and the concurrent daily rate of Na+ excretion showed that patients with increased IGF-I were low-renin hypertensives and patients with normal IGF-I were normal-renin hypertensives. These results indicate that an association exists between exaggerated circulating levels of IGF-I and abnormalities of renal function present in some patients with essential hypertension. It is suggested that IGF-I can play a role in low-renin essential hypertension.

The antihypertensive effect of verapamil in patients with chronic renal failure

Abstract: The calcium antagonist verapamil has been demonstrated to be effective in reducing hypertension in patients in whom sodium intake was not restricted. The present study evaluated the effect of verapamil in reducing hypertension in patients with chronic renal failure on low or high sodium diets. Also, the present study evaluated the effect of verapamil on proteinuria in chronic renal failure patients who were administered a normal and low protein diet. The results reveal that verapamil-SR 240 mg daily is effective in reducing hypertension in patients with chronic renal failure and the effect of verapamil is equal in patients on a high or low sodium intake. In addition, verapamil-SR 240 mg daily is effective in maintaining reduced proteinuria in chronic renal failure patients on low protein diet and may prevent proteinuria in such patients on a normal protein diet. Therefore, verapamil-SR 240 mg daily appears to be an excellent choice for the treatment of hypertensive chronic renal failure patients.