The role of nitric oxide in the lungs is that of a vasodilator and a bronchodilator. Even though nitric oxide derived oxidants play a significant role as weapons against pathogens, they also play a part in the pathogenesis of asthma as well as inflammatory conditions by modulating cellular function and damaging the airway.
The neuronal nitric oxide synthase (nNOS) commonly associated with neurons is expressed in the airway nerves in the lung. nNOS contributes to the activity of nonadrenergic, noncholinergic (NANC) in airway nerves. The nitric oxide produced by the action of nNOS primarily serves as a bronchodilator of the smooth muscles in the airways.
In addition to the nitric oxide produced by the nNOS, the endothelial cell nitric oxide synthase (ecNOS) produces nitric oxide within the endothelial cells of both bronchial and pulmonary circulations. ecNOS helps in regulating the vascular smooth muscle and controls blood pressure.
The Role of Nitric Oxide in the Lungs
In order to understand the effect of nitric oxide in the lungs, you have to appreciate two broad categories of biological activities which are cGMP production and reactive nitrogen species generation.
Nitric Oxide and cGMP
Nitric oxide is an endothelial relaxant in the smooth muscles. In addition, it relaxes other smooth muscles which include airway smooth muscles that dilate the bronchioles. The effect of nitric oxide in relaxing the smooth muscles is dependent on its capacity to bind to guanylate cyclase, a process that results in the formation of cGMP.
Reactive Nitrogen Species
Nitric oxide exerts an oxidative influence directly and indirectly through its reactions with various biomolecules and its interaction with glutathione respectively. Even though nitric oxide has a capacity to participate in oxidative processes, many of its oxidant reactions are mediated by its derivatives one of which is Peroxynitrite. Peroxynitrite has the potential to cause oxidative nitration of tyrosine residuals present in proteins, a process that leads to the formation of 3-nitrotryosine. This process has been linked to inflammatory disorders including asthma, cystic fibrosis, chronic obstructive pulmonary disease (COPD) and emphysema.
Asthma is a disease associated with increases in nitric oxide concentration in exhaled air. In the treatment of asthma, nitric oxide decreases bronchial responsiveness through a relaxation of the smooth muscles. This allows air to pass freely and hence make breathing less frustrating. Nitric oxide is also a modulator of the inflammatory response. Inhibition of the production of nitric oxide, therefore, leads to the development of eosinophilic inflammation that causes asthma. By taking nitric oxide boosters, airway eosinophilia is suppressed, and the patient receives relief from the effects of asthma.
Chronic obstructive pulmonary disease is also a condition of the lungs that result from a partial blockage of the airways. Nitric oxide plays a key role in dilating both the bronchioles and blood vessels that supply adequate oxygen to the tissues and the nerves system to help in relaxing the smooth muscles of the airway lining. This leads to opening and clearing up of the pulmonary passages. The same mechanism works in patients suffering from emphysema.
NO boosters contain powerful ingredients that are naturally extracted hence free from side effects. Through the action of these ingredients, these supplements boost the production of nitric oxide in the body. As a matter of fact, patients who have been administered with the right doses of nitric oxide supplements have shown an impressive response. The ingredients to look for when buying a nitric oxide booster include L-citrulline, Vinpocetine, beetroot and Hawthorn.