Characterization of the renal response to protein ingestion in dogs with experimentally induced renal failure.
Effects of a protein meal (2.7 g of casein/kg of body weight) on glomerular filtration rate (GFR) and renal plasma flow (RPF) were assessed in dogs after 15/16 nephrectomy (n = 10), and were compared with observations in dogs with intact kidneys (n = 5). Increase in GFR and RPF was observed in both groups of dogs between 1.5 and 8 hours after protein ingestion. A maximal value for GFR was observed between 4 and 5 hours after protein ingestion in dogs of both groups. Enhancement of urinary protein excretion was evident in partially nephrectomized dogs after protein ingestion (P less than 0.05), a result that was confirmed by 24-hour total urine collection from partially nephrectomized dogs fed a balanced ration. A qualitatively similar vasodilatory response was observed in partially nephrectomized dogs and in dogs with intact kidneys, and the mean maximal increase of GFR and RPF expressed as a percentage of baseline values in the latter dogs (47.0 +/- 8.1 and 43.6 +/- 10.3%, respectively) exceeded that observed in partially nephrectomized dogs (20.8 +/- 2.2 and 22.7 +/- 6.3%, respectively; P less than 0.01). The incremental response of the kidneys to protein ingestion was directly related to the degree of renal function, as reflected in the linear regression relationship between the incremental increase in GFR and the baseline value for GFR (P less than 0.01, R2 = 0.721).
Brown
S A
SA
Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Georgia, Athens 30602.
Finco
D R
DR
D000818:Animals; D003404:Creatinine / Q000652:urine; D004044:Dietary Proteins / Q000494:pharmacology*; D004283:Dog Diseases / Q000503:physiopathology*; D004285:Dogs; D005260:Female; D005919:Glomerular Filtration Rate; D007668:Kidney / Q000098:blood supply / Q000503:physiopathology*; D007676:Kidney Failure, Chronic / Q000503:physiopathology / Q000662:veterinary*; D008297:Male; D009392:Nephrectomy / Q000662:veterinary; D011507:Proteinuria / Q000662:veterinary; D012039:Regional Blood Flow; D012044:Regression Analysis; D013997:Time Factors
D004044:Dietary Proteins; D003404:Creatinine