Related Experiment Video
Updated: Feb 7, 2026

Analytical Techniques for Assaying Nitric Oxide Bioactivity
Published on: June 18, 2012
Elevated alveolar nitric oxide is linked to poor aerobic capacity and chronotropic incompetence in liver transplant
S Hulo1,2, J L Edme1,2, J Inamo3
1Service d'Explorations Fonctionnelles Respiratoires, Hôpital Calmette, CHU Lille, F-59000, France.
Background & Aims:
Increased nitric oxide is involved in abnormal hemodynamic parameters and respiratory function of cirrhotic patients. We aimed to quantify partitioning exhaled nitric oxide measurements in exhaled air in liver transplantation (LT) candidates and evaluate their relationships with chronotropic incompetence and aerobic capacity.
Methods:
We compared exhaled nitric oxide (NO) measurements, heart rate response and peak oxygen uptake during incremental exercise in liver transplantation candidates to those of controls.
Results:
As opposed to healthy control subjects, LT candidates displayed elevated alveolar NO, blunted chronotropic response and reduced V'O2 at maximal exercise. In LT candidates, median peak V'O2 was 18.7 ml kg-1 min-1 (interquartile range (IQR) 16.2; 21.8), corresponding to 65% (IQR 57; 72) of the predicted value. Compared with controls, LT candidates had increased levels of alveolar NO (median (IQR) 2.0 (1.2; 2.2) versus 3.1 (2.3; 4.5), p < 0.001). In controls, no relations were found between alveolar NO and V'O2 peak or heart rate reserve whereas in cirrhotic patients, negative correlations and negative slopes were found between alveolar NO and V'O2 peak and heart rate reserve decrease.
Conclusions:
Increasing alveolar NO could be a specific pathophysiological condition limiting aerobic capacity in LT candidates.
Related Concept Videos
Nitric Oxide Signaling Pathway
Lung Capacity
Freezing Point Depression and Boiling Point Elevation
The boiling point of a liquid is the temperature at which its vapor pressure is equal to ambient atmospheric pressure. Since the vapor pressure of a solution is lowered due to the presence of nonvolatile solutes, it stands to reason that the solution’s boiling point will subsequently be increased. Vapor pressure increases with temperature, and so a solution will require a higher temperature than will pure solvent to achieve any given vapor pressure, including one...
Oxidation Numbers
Alveoli and Alveolar Ducts
Covalently Linked Protein Regulators
These groups modify specific amino acids in a protein....

