The discovery of "taste receptors" in the lungs rather than on the tongue could point the way to new medicines for asthma, it is suggested.
Experiments in mice revealed that bombarding the receptors with bitter-tasting compounds helped open the airways, which could ease breathing. The University of Maryland study, published in Nature Medicine, may have implications for other lung diseases.
Asthma UK warned that any new drug would not arrive for some time.
The "taste receptors" discovered in the smooth muscle of the lungs are not the same as those clustered in taste buds in the mouth. They do not send signals to the brain, and yet, when exposed to bitter substances, they still respond. It was the nature of that response that surprised researchers, who assumed their presence was as a defence against noxious gases, triggering a tightening of the airways and coughing.
In fact, the mouse experiments revealed that exactly the reverse was true.