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Uraemia: is urea more important than we think?
1University Department of Pathology, Royal Victoria Infirmary, Newcastle upon Tyne, UK.
Lancet (London, England)
|December 7, 1991
Summary
Certain animals tolerate high urea levels by accumulating protective methylamines. These osmolytes may also play a role in human kidney function and chronic renal failure treatment.
Area of Science:
- Biochemistry
- Physiology
- Nephrology
Background:
- Urea is an osmolyte accumulated by some animals, despite its protein-impairing effects.
- These animals counteract urea's effects using methylamines, which protect proteins.
Purpose of the Study:
- To investigate the potential confounding role of methylamines in previous urea toxicity studies.
- To explore the therapeutic potential of methylamines in human uremia.
Main Methods:
- Literature review and analysis of existing data on osmolytes and urea toxicity.
- Comparative analysis of osmolyte concentrations in different species and physiological conditions.
Main Results:
- Methylamines offset urea's detrimental effects on protein function in osmolyte-accumulating organisms.
- Methylamines are present in the mammalian kidney medulla and in the plasma of humans with chronic renal failure.
Conclusions:
- Previous studies on urea's contribution to uremia may be confounded by the presence of protective methylamines.
- Naturally occurring methylamines or related compounds could offer therapeutic benefits for uremia.
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