Objective—To determine plasma and urine concentrations
of retinol, retinyl esters, retinol-binding protein
(RBP), and Tamm-Horsfall protein (THP) in dogs
with chronic renal disease (CRD).
Animals—17 dogs with naturally developing CRD and
21 healthy control dogs.
Procedure—A diagnosis of CRD was established on
the basis of clinical signs, plasma concentrations of
creatinine and urea, and results of urinalysis.
Concentrations of retinol and retinyl esters were measured
by use of reverse-phase high-performance liquid
chromatography. Concentrations of RBP and THP
were measured by use of sensitive ELISA systems.
Results—Dogs with CRD had higher plasma concentrations
of retinol, which were not paralleled by differences
in plasma concentrations of RBP. Calculated
ratio of urinary total vitamin A (sum of concentrations
of retinol and retinyl esters to creatinine concentration)
and ratio of the concentration of urinary retinyl esters
to creatinine concentration did not differ between
groups. However, we detected a significantly higher
retinol-to-creatinine ratio in the urine of dogs with
CRD, which was paralleled by a higher urinary RBP-to-creatinine
ratio. Thus, in dogs with CRD, the estimated
fractional clearance of total vitamin A, retinol, and RBP
was increased. Furthermore, dogs with CRD had a
reduced urinary THP-to-creatinine ratio.
Conclusions and Clinical Relevance—Results of
this study documented that CRD affects the concentrations
of retinol in plasma and urine of dogs.
Analysis of the data indicates that measurement of
urinary RBP and urinary THP concentrations provides
valuable information that can be helpful in follow-up
monitoring of dogs with CRD. (Am J Vet Res 2003:64:874–879)
Objective—To evaluate excretion of urinary albumin (UAlb) and urinary retinol-binding protein (URBP) in dogs with naturally occurring renal disease.
Animals—64 client-owned dogs.
Procedures—Dogs were assigned to groups according to plasma creatinine concentration, urinary protein-to-urinary creatinine ratio (UP:UC), and exogenous plasma creatinine clearance (P-ClCr) rates: group A (n = 8), nonazotemic (plasma creatinine < 125 μmol/L) and nonproteinuric (UP:UC < 0.2) with P-ClCr rate > 90 mL/min/m2; group B (26), nonazotemic and nonproteinuric with P-ClCr rate 50 to 89 mL/min/m2; group C (7), nonazotemic but proteinuric with P-ClCr rate 53 to 98 mL/min/m2; group D (8), azotemic and borderline proteinuric with P-ClCr rate 22 to 45 mL/min/m2); and group E (15), azotemic and proteinuric (P-ClCr not evaluated). The UAlb and URBP concentrations were measured via ELISA; UAlb-to-urinary creatinine (UAlb:UC) and URBP-to-urinary creatinine (URBP:UC) ratios were determined.
Results—UAlb:UC and URBP:UC did not differ between groups A and B. Increased UAlb: UCs and URBP:UCs were paralleled by increased UP:UCs in groups C, D, and E relative to values from groups A and B, independent of azotemia. There were significant positive correlations of UP:UC with UAlb:UC and of UAlb:UC with URBP:UC (r = 0.82 and 0.46, respectively). However, UP:UC, UAlb:UC, and URBP:UC were not significantly correlated with P-ClCr rate.
Conclusions and Clinical Relevance—UAlb and URBP concentrations were paralleled by urinary protein concentrations and may be useful in assessing renal management of plasma proteins. Determination of urinary protein, UAlb, or URBP concentration was not sufficiently sensitive to detect reduced P-ClCr in nonazotemic dogs. (Am J Vet Res 2010;71:1387—1394)
Objective—To evaluate vascular endothelial growth factor (VEGF) concentrations in canine blood products treated with or without a leukoreduction filter.
Sample—10 canine blood donors.
Procedures—Dogs underwent blood collection. Five of 10 units were leukoreduced prior to separation into packed RBCs and fresh frozen plasma (FFP). Concentrations of VEGF were measured by ELISA in plasma supernatants from aliquots of packed RBCs obtained immediately after separation and on days 7, 14, and 21 of storage. Fresh frozen plasma samples of 2 filtered and 2 nonfiltered units were examined after storage.
Results—RBC counts in whole blood before and after leukoreduction did not differ significantly, but WBCs and platelets were removed effectively. The VEGF concentration was lower than the detection limit (9 pg/mL) in 9 of 10 plasma samples and in all packed RBC and FFP units immediately after separation. The median VEGF concentrations in 5 nonfiltered packed RBC units were 37, 164, and 110 pg/mL on days 7, 14, and 21 of storage, respectively. In 5 filtered packed RBC and all FFP units, VEGF concentrations remained lower than the detection limit.
Conclusions and Clinical Relevance—Leukoreduction filters were effective in preventing the release of VEGF during storage of canine RBC products.