title: Influence of allopurinol and two diets on 24-hour urinary excretions of uric acid, xanthine, and ammonia by healthy dogs.
abstract: Hyperxanthinuria and xanthine uroliths have been recognized with increased frequency in dogs with ammonium urate uroliths that had been given allopurinol. We hypothesized that dietary modification might reduce the magnitude of uric acid and xanthine excretion in urine of dogs given allopurinol. To test this hypothesis, excretion of metabolites, volume, and pH were determined in 24-hour urine samples produced by 6 healthy Beagles during periods of allopurinol administration (15 mg/kg of body weight, PO, q 12 h) and consumption of 2 special purpose diets: a 10.4% protein (dry matter), casein-based diet and a 31.4% protein (dry matter), meat-based diet. Significantly lower values of uric acid (P = 0.004), xanthine (P = 0.003), ammonia (P = 0.0002), net acid (P = 0.0001), titratable acid (P = 0.0002), and creatinine (P = 0.01) excreted during a 24-hour period were detected when dogs consumed the casein-based diet and were given allopurinol, compared with the 24-hour period when the same dogs consumed the meat-based diet and were given allopurinol. For the same 24-hour period, urine pH values, urine volumes, and urine bicarbonate values were significantly (P = 0.0004, P = 0.04, and P = 0.002, respectively) higher during the period when the dogs were fed the casein-based diet and given allopurinol than when they were fed the meat-based diet and given allopurinol. Endogenous creatinine clearance was significantly (P = 0.006) lower when dogs were fed the casein-based diet and given allopurinol than when they were fed the meat-based diet and given allopurinol.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Minnesota, St Paul 55108, USA.
authors.forename: J W
authors.initials: JW
authors.lastname: Bartges
authors.forename: C A
authors.initials: CA
authors.lastname: Osborne
authors.forename: L J
authors.initials: LJ
authors.lastname: Felice
authors.forename: L K
authors.initials: LK
authors.lastname: Unger
authors.forename: M
authors.initials: M
authors.lastname: Chen
mesh_terms: D000493:Allopurinol / Q000494:pharmacology*; D000641:Ammonia / Q000652:urine*; D000818:Animals; D018753:Diet, Protein-Restricted / Q000662:veterinary; D004044:Dietary Proteins / Q000494:pharmacology*; D004285:Dogs / Q000652:urine*; D005260:Female; D018565:Food-Drug Interactions; D014527:Uric Acid / Q000097:blood / Q000652:urine*; D014545:Urinary Calculi / Q000628:therapy / Q000662:veterinary; D014970:Xanthines / Q000097:blood / Q000652:urine*
chemical_list: D004044:Dietary Proteins; D014970:Xanthines; D014527:Uric Acid; D000493:Allopurinol; D000641:Ammonia