Dissociation between antiproteinuric and antihypertensive effect of angiotensin converting enzyme inhibitors in rats.

To clarify whether angiotensin converting enzyme (ACE) inhibitors prevent progressive renal injury directly by their antihypertensive effect we administered the ACE inhibitor lisinopril to male MWF/Ztm rats as a single daily dose that lowered blood pressure for only 9 of 24 h. We investigated the effects of this treatment in short- and long-term studies and compared them with another antihypertensive drug, the calcium channel blocker nitrendipine, given to partially control blood pressure as done with the ACE inhibitor. In untreated animals systemic hypertension, proteinuria, and glomerulosclerosis developed spontaneously with age, and lisinopril reduced systemic hypertension and prevented proteinuria and glomerular lesions.

Pathophysiologic implications of proteinuria in a rat model of progressive glomerular injury.

Background: Males of a substrain of Munich-Wistar rats (MWF/Ztm), selected for their large number of superficial glomeruli, develop spontaneous proteinuria with age, whereas females of this strain have a normal urinary protein excretion rate.

Experimental Design: We investigated the relationship between functional and structural glomerular alterations in four groups of male and female MWF/Ztm rats, respectively at 20 and 35 weeks of age. Systolic blood pressure, urinary protein excretion and composition of urinary proteins were periodically measured during the study.

Renoprotective effect of low iron diet and its consequence on glomerular hemodynamics.

It has been reported that anemia limits renal injury in rats with reduced renal mass. We studied the effect of a low iron diet, given to reduce hematocrit, on urinary protein excretion and glomerular function in male MWF/Ztm rats, which spontaneously develop proteinuria and glomerular sclerosis. At 20 weeks of age, micropuncture and glomerular volume measurements were performed in untreated rats fed standard chow and in rats fed an isocaloric diet with low iron (5 mg/kg) content.

Angiotensin converting enzyme inhibition ameliorates glomerular filtration of macromolecules and water and lessens glomerular injury in the rat.

The effect of enalapril on glomerular hemodynamics and permselectivity and on subsequent sclerosis was studied in male MWF/Ztm rats which spontaneously develop proteinuria and glomerular structural damage. Untreated group 1 and enalapril-treated group 2 (50 mg/liter, in the drinking water) underwent micropuncture studies after 2 mo of observation. After the same period of treatment, group 3 (untreated) and group 4 (enalapril treated) were used for determination of whole-kidney function and neutral dextran clearances.

Sex related differences in glomerular ultrafiltration and proteinuria in Munich-Wistar rats.

Munich-Wistar rats (MWF/Ztm), originally selected for high number of superficial glomeruli, were used to correlate abnormal urinary protein excretion with glomerular hemodynamics and glomerular morphology. Two animal groups were used, one of male and one of female rats. They were kept periodically in metabolic cages to determine urinary protein excretion.