Abnormal smooth muscle behaviour in asthma: toward an in vivo test [ 2001 - 2003 ]

Research Grant

Researchers: Ann Woolcock (Principal investigator) ,  Prof Gregory King (Principal investigator) ,  Dr Cheryl Salome

Brief description In order to understand asthma better, and to improve our ability both to prevent and to treat the disease, we need to understand why the airways of people with asthma narrow too easily and too much. Airway hyperresponsiveness is almost certainly a downstream consequence of several different abnormalities. Airway inflammation, resulting from an allergic reaction in the airways, probably plays a major role. It is also likely that the smooth muscle in the airways contributes to airway narrowing, but at present we have no way to measure airway behaviour in the living human. In this project we will examine the response of the airways to a deep breath, to determine if this is an indicator of smooth muscle behaviour. When the airways are narrowed, taking a deep breath stretches them and helps to overcome the narrowing. It is well known that this stretching mechanism is impaired in asthma, probably as a result of inflammatory changes to the airway wall. What is less well known is that after the airway has been stretched by a deep breath, it re-narrows, and there is new evidence that the rate of re-narrowing is increased in asthma. Based on our knowledge of how the smooth muscle behaves in the organ bath, and of the types of abnormal behaviour found in muscle from allergic and some asthmatic people, it seems likely that the rate of airway re-narrowing following a deep breath is an indicator of smooth muscle behaviour. This hypothesis has not been tested before. If we can establish that the rate of re-narrowing is an indicator of smooth muscle behaviour, we can then determine if abnormal muscle behaviour occurs in asthma, and examine the factors associated with abnormal muscle behaviour. This will improve our understanding of the basic abnormalities in asthma, and facilitate studies to see if this test can predict who is at risk from developing asthma. Evidence that smooth muscle behaviour is abnormal in asthma may suggest new directions for drug therapy.

Funding Amount $AUD 196,527.54

Funding Scheme NHMRC Project Grants

Notes Standard Project Grant