Bronchodilation is the dilation of the airways in the
lungs
The lungs are the primary organs of the respiratory system in humans and most other animals, including some snails and a small number of fish. In mammals and most other vertebrates, two lungs are located near the backbone on either side ...
due to the relaxation of surrounding
smooth muscle. It is the opposite of
bronchoconstriction
Bronchoconstriction is the constriction of the airways in the lungs due to the tightening of surrounding smooth muscle, with consequent coughing, wheezing, and shortness of breath.
Causes
The condition has a number of causes, the most common be ...
.
Inducers
Bronchodilator
A bronchodilator or broncholytic (although the latter occasionally includes secretory inhibition as well) is a substance that dilates the bronchi and bronchioles, decreasing resistance in the respiratory airway and increasing airflow to the lung ...
s induce bronchodilatation, while there are many drugs that may induce bronchoconstriction.
Tobacco
Tobacco is the common name of several plants in the genus '' Nicotiana'' of the family Solanaceae, and the general term for any product prepared from the cured leaves of these plants. More than 70 species of tobacco are known, but the ...
can cure one typology of
asthma
Asthma is a long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms, reversible airflow obstruction, and easily triggered bronchospasms. Symptoms include episodes of wheezing, co ...
.
['' Encyclopedia Federico Motta Editore'']
Autonomic nervous system response:
A sympathetic response is brought about by the sympathetic autonomic nervous system. Drugs that bring about sympathetic responses are called sympathomimetics, whereas drugs that inhibit activation of the sympathetic nervous system are called sympatholytics.
One example of a bronchoconstrictor is
prostaglandin E2.
Carbon dioxide is the most powerful natural bronchodilator.
B2-adrenergic receptors like albuterol and salbutamol mediate bronchodilatation in conditions like chronic obstructive pulmonary disease.
References
Respiration
{{respiratory-stub