Molecular mechanisms of renal ammonia transport.
Acid-base homeostasis to a great extent relies on renal ammonia metabolism. In the past several years, seminal studies have generated important new insights into the mechanisms of renal ammonia transport. In particular, the theory that ammonia transport occurs almost exclusively through nonionic NH(3) diffusion and NH(4)(+) trapping has given way to a model postulating that a variety of proteins specifically transport NH(3) and NH(4)(+) and that this transport is critical for normal ammonia metabolism. Many of these proteins transport primarily H(+) or K(+) but also transport NH(4)(+). Nonerythroid Rh glycoproteins transport ammonia and may represent critical facilitators of ammonia transport in the kidney. This review discusses the underlying aspects of renal ammonia transport as well as specific proteins with important roles in renal ammonia transport.
Weiner
I David
ID
Nephrology Section, North Florida/South Georgia Veterans Health System, and Division of Nephrology, Hypertension and Transplantation, University of Florida, Gainesville, Florida 32608, USA. weineid@ufl.edu
Hamm
L Lee
LL
D000641:Ammonia / Q000378:metabolism*; D000818:Animals; D001693:Biological Transport, Active / Q000502:physiology*; D002352:Carrier Proteins / Q000378:metabolism; D006801:Humans; D007668:Kidney / Q000378:metabolism*
D002352:Carrier Proteins; D000641:Ammonia