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Updated: Jul 21, 2026

Fast and Accurate Exhaled Breath Ammonia Measurement
Published on: June 11, 2014
Ammonia functions as a regulatory molecule to mediate adjustments in glomerular filtration rate in response to
1Department of Medicine, Queen's University, Kingston, Ontario, Canada. singerm@post.queensu.ca
Abstract:
In mammals, varying in size from mouse to elephant there is a close linkage between metabolic rate (MR) and glomerular filtration rate (GFR). This linkage has evolved because of the necessity to excrete nitrogenous wastes generated predominately by amino acid catabolism. A similar linkage is observed in birds, reptiles and fish, although in the latter vertebrate group gill excretion rate and GFR need to be considered as an interdependent co-ordinated system. A change in the rate of amino acid catabolism will result in a change in the rate of production of nitrogenous wastes requiring excretion and hence GFR (or GFR plus gill excretory rate in fish) must be appropriately re-set. It is hypothesized that ammonia functions as a regulatory molecule to mediate adjustments in excretory rate (GFR or GFR plus gill excretory rate) in response to such changes in amino acid catabolism.
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