London: Human lungs can detect bitter tastes the same way as the tongue can, potentially paving the way to new treatments for asthma.
The team from the University of Maryland School of Medicine, US, found that contrary to what they thought, the airways in the lungs opened in response to a bitter taste.
Senior study author Stephen Liggett said: "I initially thought the bitter-taste receptors in the lungs would prompt a `fight or flight` response to a noxious inhaleant causing chest tightness and coughing so you would leave the toxic environment, but that`s not what we found," reports a newspaper.
"It turns out that the bitter compounds worked the opposite way from what we thought," according to the journal Nature Medicine.
"They all opened the airway more profoundly than any known drug that we have for treatment of asthma or chronic obstructive pulmonary disease."
"This could replace or enhance what is now in use and represents a completely new approach," said Liggett.
The team tested bitter substances on human and mouse airways. Quinine and chloroquinine, normally used to combat malaria, were used as they taste bitter along with the artificial sweetner saccharin, which has a bitter aftertaste.
Liggett said: "Based on our research we think that the best drugs would be chemical modifications of bitter compounds which would be aerosolised and then inhaled into the lungs in an inhaler."
The discovery was made by accident when the team were studying muscle receptors that cause contraction and relaxation in the lungs.
It is thought that the bitter substances affect how calcium controls muscles.