NHLBI IN THE PRESS

Study reveals the mechanism of bronchial spasm

NHLBI-funded researchers have developed a model of the human respiratory airways that, by mimicking its behaviors, revealed the mechanism of asthmatic bronchial spasms. The findings were reported in the Nature Biomedical Engineering journal. 
 
Bronchial spasms, also known as bronchospasms, are muscle contractions in the airway that cause difficulty breathing in patients suffering from serious respiratory diseases such as asthma or COPD. 

According to the study, muscle contractions triggered by allergens or other small substances in the airways initially respond to positive feedback, meaning that initial contractions lead to more contractions. But eventually, the contractions stop when smooth muscle relaxes. The study found that in the asthmatic model — a microdevice with cells taken from an asthma patient — this relaxation takes much longer than in the nonasthmatic model, explaining why asthmatic patients experience airway constriction for a longer period of time