Related Experiment Video
Updated: Jul 20, 2026

A Novel Inhalation Mask System to Deliver High Concentrations of Nitric Oxide Gas in Spontaneously Breathing Subjects
Published on: May 4, 2021
Endogenous nitric oxide in expired air: effects of acute exercise in humans
1Department of Pharmaceutics, School of Pharmacy, State University of New York at Buffalo 14260.
Abstract:
Nitric oxide (NO) is present in the exhaled breath of humans and experimental animals, but its physiologic role and cellular source(s) remain to be determined. Possible sites of origin are pulmonary endothelial cells and/or resident macrophages. Here we have tested the hypothesis that changes in cardiovascular status can alter the apparent pulmonary excretion of NO. Exercise on a stationary bicycle produced rapid and reversible increases in pulmonary NO excretion rate, and changes in NO excretion rate during exercise were well correlated with observed changes in heart rate. These results suggest that changes in expired NO during exercise are related to corresponding cardiovascular responses.
Related Concept Videos
Nitric Oxide Signaling Pathway
Physiological Control of Respiration
Breathing, a seemingly passive process, is regulated by the respiratory center in the brainstem. This center coordinates the involuntary control of respirations, which means it occurs without conscious effort, ensuring a smooth and uninterrupted pattern.
Regulation of Ventilation
The body maintains ventilation by monitoring levels of carbon dioxide (CO2), oxygen (O2), and hydrogen ion concentration (pH) in the arterial blood. Among these factors, the level of CO2 plays a crucial...
Respiration and Gaseous Exchange
Respiration involves the exchange of gases, especially oxygen (O2) and carbon dioxide (CO2), between the alveoli and body cells, a process facilitated by blood circulation. As a result, the cardiovascular system, which involves the...
Antianginal Drugs: Nitrates and β-Blockers
Organic nitrates, such as nitroglycerin, play a pivotal role. Once metabolized, they liberate nitric oxide, a molecular marvel. Nitric oxide triggers guanylyl cyclase and augments cGMP production. This biochemical cascade orchestrates the relaxation of vascular smooth muscles, ushering in vasodilation and enhancing coronary blood flow. Administered...
Exercise and Cardiovascular Response
Light to moderate physical activity initiates a series of interconnected responses in the body. The heart rate modestly increases in anticipation of the workout, followed by widespread vasodilation as oxygen consumption by skeletal muscles increases. This results in decreased peripheral resistance, increased capillary blood flow, and accelerated...
Chemical Factors Affecting Respiration Centers
CO2 has a potent influence on respiration and is strictly regulated. Under...

