Time course of gastrointestinal tract permeability to chromium 51-labeled ethylenediaminetetraacetate in healthy dogs.
OBJECTIVE
To establish values for gastrointestinal tract permeation by chromium 51-labeled ethylenediaminetetraacetate (51Cr-labeled EDTA) in healthy adult dogs, and to evaluate the time course for 51Cr-labeled EDTA absorption over a 24-hour period after its administration, in an effort to define a shorter, more practical collection method.


METHODS
6 healthy adult mixed-breed dogs.


METHODS
After an 18-hour nonfeeding period, each dog was given a solution containing 50 microCi of 51Cr-labeled EDTA in deionized water (10 ml/kg of body weight) by stomach tube. Complete urine collection was done at 2, 4, 6, and 24 hours after 51Cr-labeled EDTA administration. Five-milliliter samples of urine were counted for 15 minutes in a gamma counter, and radioactivity in urine was expressed as a percentage of the orally administered dose.


RESULTS
Median (range) 24-hour urinary recovery of 51Cr-labeled EDTA after 24 hours was 15.1 (12.7 to 20.3)%. Urine collected at 2, 4, and 6 hours contained 1.0 (0.2 to 3.5)%, 6.5 (2.2 to 8.7)%, and 10.0 (8.1 to 11.7)% of the administered 51Cr-labeled EDTA, respectively. Urine passed during the first 6 hours contained, on average, 67 (54 to 77)% of the total 24-hour urine recovery.


CONCLUSIONS
6-hour urinary recovery of 51Cr-EDTA provides a potential alternative to 24-hour recovery. This shorter collection period may more specifically reflect small intestinal permeability.
Marks
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SL
Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis 95616, USA.
Williams
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DA
D000818:Animals; D002860:Chromium Radioisotopes / Q000493:pharmacokinetics; D004064:Digestive System / Q000378:metabolism*; D004285:Dogs / Q000378:metabolism*; D004492:Edetic Acid / Q000493:pharmacokinetics*; D005260:Female; D007408:Intestinal Absorption; D008297:Male; D010539:Permeability; D013997:Time Factors
D002860:Chromium Radioisotopes; D004492:Edetic Acid