APStracts 2:0052F, 1995.

Tubulointerstitial injury and impaired renal function after recovery from acute puromycin nephrosis. Baboolal, Keshwar, and Timothy W. Meyer. Departments of Medicine, Palo Alto VAMC and Stanford University, Palo Alto, CA 94304

APStracts 2:0052F, 1995.

Renal function was assessed at two weeks and at eight weeks after infusion of puromycin into the left renal artery of Munich Wistar rats. At two weeks, albumin excretion averaged 90+/-12 [mu]g/min in the left kidney and 4+/-1 [mu]g/min in the right kidney. Unilateral nephrosis was accompanied by reduction in the GFR (left 0.71+/-0.04 ml/min, right 1.31+/-0.02 ml/min) and by impaired excretion of sodium (FENa: left 0.025+/-0.004 %, right 0.064+/-0.006 %). Reductions in the GFR and FENa in the nephrotic kidney were not reversed by acute AII receptor blockade with losartan. At eight weeks, albumin excretion averaged 6+/-1 [mu]g/min in the left kidney and 8+/-1 [mu]g/min in the right kidney. Recovery from nephrosis was accompanied by persistent reduction in the GFR (left 1.05+/-0.05 ml/min, right 1.41+/-0.05 ml/min) and impairment of sodium excretion in the previously nephrotic left kidney (FENa: left 0.031+/-0.004 %, right 0.051+/-0.004 %). Losartan again did not return the GFR and FENa toward normal. The reductions in the GFR and FENa in the previously nephrotic left kidney were associated with structural changes including intratubular casts, an increased fractional volume of the interstitium (Vv-int: left 25+/-1 %, right 15+/-1 %), tubular atrophy (Vv-tub: left 66+/-2%, right 77+/-1 %) and glomerular collapse (left 15+/-2 %, right 1+/-1 %). These findings suggest the tubulointerstitial injury can cause persistent reduction in the GFR and impairment of sodium excretion after recovery from acute nephrosis.

Received 17 October 1994; accepted in final form 20 March 1995.
APS Manuscript Number F373-4.
Article publication pending Am. J. Physiol. (Renal Fluid Electrolyte
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 19 April 1995.