title: Relationship between urinary Tamm-Horsfall protein excretion and renal function in dogs with naturally occurring renal disease.
abstract: BACKGROUND
  Tamm-Horsfall protein (THP) is physiologically excreted in urine, but little is known about the role of THP in the diagnosis of renal disease in dogs.
  
  
  OBJECTIVE
  The aim of this study was to evaluate to which extent naturally occurring renal disease affects the urinary excretion of THP.
  
  
  METHODS
  Dogs were divided into 5 groups according to plasma creatinine concentration, urinary protein-to-creatinine ratio (UP/UC), and exogenous plasma creatinine clearance (P-ClCr ) rates: Group A (healthy control dogs; n = 8), nonazotemic and nonproteinuric dogs, with P-ClCr rates > 90 mL/min/m(2) ; group B (n = 25), nonazotemic and nonproteinuric dogs with reduced P-ClCr rates (51-89 mL/min/m(2) ); group C (n = 7), nonazotemic but proteinuric dogs with P-ClCr rates 53-98 mL/min/m(2) ; group D (n = 8), azotemic and borderline proteinuric dogs (P-ClCr rates: 22-45 mL/min/m(2) ); and group E (n = 15), azotemic and proteinuric dogs (not tested for P-ClCr ). THP was measured by quantitative Western blot analysis, and the ratio of THP-to-urinary creatinine (THP/UC) was calculated.
  
  
  RESULTS
  The THP/UC concentrations were not different among dogs of groups A-D, but were reduced in dogs of group E (P < .001). THP/UC correlated negatively with serum creatinine (P < .01) and UP/UC (P < .01), but was not significantly associated with P-ClCr .
  
  
  CONCLUSIONS
  Decreased levels of THP/UC were present in moderately to severely azotemic and proteinuric dogs. This suggests tubular injury in these dogs and that THP might be useful as urinary marker to study the pathogenesis of renal disease.
authors.affiliation: Institute of Nutritional Science, University of Potsdam, Nuthetal, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Raila
authors.forename: Florian J
authors.initials: FJ
authors.lastname: Schweigert
authors.forename: Barbara
authors.initials: B
authors.lastname: Kohn
mesh_terms: D000818:Animals; D053099:Azotemia / Q000662:veterinary; D015415:Biomarkers / Q000652:urine; D003404:Creatinine / Q000097:blood; D004283:Dog Diseases / Q000503:physiopathology*; D004285:Dogs; D005260:Female; D007674:Kidney Diseases / Q000503:physiopathology / Q000662:veterinary*; D007686:Kidney Tubules, Distal / Q000293:injuries* / Q000503:physiopathology; D008297:Male; D011507:Proteinuria / Q000662:veterinary; D058949:Uromodulin / Q000378:metabolism* / Q000652:urine
chemical_list: D015415:Biomarkers; D058949:Uromodulin; D003404:Creatinine
keywords: Distal tubules; dog; kidney; lower nephron; proteinuria; urine