SSS 2010-10-25（在线收听）

This is Scientific American’s 60-Second Science. I’m Cynthia Graber. This will just take a minute.

Take a deep breath. Taste anything? Actually, your lungs may, because scientists have discovered that the same receptors that exist on the tongue to taste bitter substances are also found on the smooth muscle of lungs.

Researchers were studying the receptors on smooth lung muscles that regulate contraction and relaxation of the airways. That’s when they made the discovery which was so unexpected that the researchers themselves were skeptical.

Finally, they became convinced that the receptors were really there, though were not clustered in taste buds as they are on the tongue. The scientists then exposed human and mouse airways to various bitter compounds to gauge the effects.

Many toxic compounds are bitter, so the researchers expect that the lung muscle to tense up and contract-- to compel the breather to move away from whatever is bitter and perhaps toxic. But, in a second surprise, bitter compounds relaxed and opened airways better than any existing asthma drug. The study is in the journal Nature Medicine.

Researchers will continue to search for the role of the receptors. Meanwhile, the work represents a surprising new lead in the search for drugs to treat asthma, emphysema or chronic bronchitis.

Thanks for the minute. For Scientific American’s 60-Second Science, I’m Cynthia Graber.