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Updated: Jun 30, 2026
08:50
5/6th Nephrectomy in Combination with High Salt Diet and Nitric Oxide Synthase Inhibition to Induce Chronic Kidney Disease in the Lewis Rat
Published on: July 3, 2013
Summary
Urea degradation in chronic uremic patients is significantly lower than in healthy individuals. Gut urea splitting does not appear to promote nitrogen conservation in these patients.
Area of Science:
- Nephrology
- Gastroenterology
- Metabolic Research
Background:
- Chronic uremia is associated with altered nitrogen metabolism.
- The role of gut urea degradation in nitrogen balance in uremic patients is not fully understood.
Purpose of the Study:
- To quantify urea degradation in chronic uremic patients.
- To assess the contribution of gut urea metabolism to nitrogen balance in uremia.
Main Methods:
- Intravenous injection of [(14)C]urea to measure urea distribution and clearance.
- Comparison of extrarenal urea clearance with renal urea clearance.
- Measurement of urea appearance rate and its correlation with urea degradation.
Main Results:
- Extrarenal urea clearance in uremic patients (3.1 L/day) was substantially lower than in normal subjects (18 L/day).
- Ammonia nitrogen formation from urea was similar to normal, attributed to elevated plasma urea levels.
- Urea production positively correlated with urea degradation, suggesting ammonia recycling back to urea.
Conclusions:
- Gut urea degradation is significantly reduced in chronic uremic patients.
- The findings do not support the hypothesis that gut urea degradation promotes nitrogen conservation in uremic patients on low-protein diets.
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