4.4 Article

Renal carbonic anhydrases are involved in the reabsorption of endogenous nitrite

Journal

NITRIC OXIDE-BIOLOGY AND CHEMISTRY
Volume 26, Issue 2, Pages 126-131

Publisher

ACADEMIC PRESS INC ELSEVIER SCIENCE
DOI: 10.1016/j.niox.2012.01.005

Keywords

Carbonic anhydrase; Homeostasis; Mass spectrometry; Nitric oxide; Nitrite; Urine

Funding

  1. Deutsche Forschungsgemeinschaft [TS 60/4-1]

Ask authors/readers for more resources

Nitrite (O=N-O-) exerts nitric oxide (NO)-related biological actions and its concentration in the circulation may be of particular importance. Nitrite is excreted in the urine. Hence, the kidney may play an important role in nitrite/NO homeostasis in the vasculature. We investigated a possible involvement of renal carbonic anhydrases (CAs) in endogenous nitrite reabsorption in the proximal tubule. The potent CA inhibitor acetazolamide was administered orally to six healthy volunteers (5 mg/kg) and nitrite was measured in spot urine samples before and after administration. Acetazolamide increased abruptly nitrite excretion in the urine, strongly suggesting that renal CAs are involved in nitrite reabsorption in healthy humans. Additional in vitro experiments support our hypothesis that nitrite reacts with CO2, analogous to the reaction of peroxynitrite (O=N-O-O-) with CO2, to form acid-labile nitrito carbonate [O=N-O-C(=O)-O-]. We assume that this reaction is catalyzed by CAs and that nitrito carbonate represents the nitrite form that is actively transported into the kidney. The significance of nitrite reabsorption in the kidney and the underlying mechanisms, notably a direct involvement of CAs in the reaction between nitrite and CO2, remain to be elucidated. (c) 2012 Elsevier Inc. All rights reserved.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.4
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available