title: The effect of protein restriction on the severity and recovery from ischemic renal failure.
abstract: The effects of chronic dietary protein restriction on ischemic renal failure were evaluated in rats subjected to 90 min of bilateral renal clamping. The rats were kept on either 20% casein (regular) diet or casein-free (protein-free) diet 10 days before and 21 days after renal injury. Rats on regular protein diet showed higher levels of BUN and serum creatinine and had a lower inulin clearance (microliter/min/100 g BW) than animals on protein-free diet (289 +/- 34 vs 582 +/- 103, p less than 0.05) 2 days after ischemia. However, the inulin clearance measured 21 days following ischemia was significantly higher in rats on regular diet (1468 +/- 181) than those maintained on protein-free diet after ischemia (560 +/- 167). When unilateral 90 min ischemia was performed in rats on regular diet, the postischemic kidneys showed an incomplete recovery of the inulin clearance (226 +/- 35) compared to the contralateral kidney (900 +/- 116), 21 days after ischemia; whereas in rats on a protein-free diet the inulin clearance averaged 106 +/- 17 in the postischemic kidney and 345 +/- 41 in the right kidney. When left renal ischemia and contralateral nephrectomy were performed, the inulin clearance was 1149 +/- 74 in rats on regular diet and 534 +/- 60 in rats on protein-free diet, 21 days following renal insult. These results suggest that protein restriction can play a protective role against renal ischemia in an initial phase, but it limits the late recovery from ischemia. The presence of a normal contralateral kidney inhibits the functional recovery of the postischemic kidney and a contralateral nephrectomy produces a compensatory functional hypertrophy of the postischemic kidney, even in rats on a protein-free diet.
authors.affiliation: Laboratório de Pesquisa Básica, Faculdade de Medicina, Universidade de São Paulo, Brasil.
authors.forename: A C
authors.initials: AC
authors.lastname: Seguro
authors.forename: M H
authors.initials: MH
authors.lastname: Shimizu
authors.forename: S B
authors.initials: SB
authors.lastname: Campos
authors.forename: A S
authors.initials: AS
authors.lastname: Rocha
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D003404:Creatinine / Q000097:blood; D004044:Dietary Proteins / Q000008:administration & dosage*; D005919:Glomerular Filtration Rate / Q000502:physiology; D007511:Ischemia / Q000503:physiopathology / Q000517:prevention & control*; D007668:Kidney / Q000098:blood supply*; D007676:Kidney Failure, Chronic / Q000503:physiopathology / Q000517:prevention & control*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D004044:Dietary Proteins; D003404:Creatinine