Dietary supplementation with L-arginine ameliorates the progression of renal disease in rats with subtotal nephrectomy.

We studied the effect of dietary supplementation with L-arginine for 6 weeks on the progression of renal disease in female Sprague-Dawley rats subjected to sham-operation (groups 1 and 2) or surgical ablation of 85% to 90% of the total renal mass (groups 3 and 4). All rats were fed a standard rat chow containing 22.8% protein. Rats in groups 1 (n = 5) and 3 (n = 9) served as controls and drank tap water ad libitum. Rats in groups 2 (n = 6) and 4 (n = 6) drank tap water supplemented with 1% L-arginine. Rats in groups 1 and 2 had similar values for glomerular and tubular function and serum chemistries 6 weeks after sham-operation. Sham-operated rats given L-arginine had significantly greater urine urea excretion than similar rats drinking tap water. Rats with subtotal nephrectomy (groups 3 and 4) had a significantly higher blood pressure, greater proteinuria, and a significantly lower plasma albumin than sham-operated rats (groups 1 and 2). Rats with remnant kidneys given 1% L-arginine (group 4) had significantly greater values for glomerular filtration rate (GFR) and P-amino hippurate (PAH) clearance than similar rats given tap water (group 3), despite comparable levels of systemic blood pressure, hematocrit, body weight, plasma chemistries, including L-arginine, and urine chemistries, except urea excretion. The remnant kidney of rats given L-arginine (group 4) had a greater number of normal or minimally abnormal glomeruli and fewer interstitial changes than that of rats given tap water (group 3).(ABSTRACT TRUNCATED AT 250 WORDS)