Scientists Discover Odor Receptors in Human Lungs

Posted on January 2, 2014

Scientists at Washington University in St. Louis and the University of Iowa have discovered that human lungs also contain odor receptors. The odor receptors in your nose are located in the membranes of nerve cells. The newly discovered odor receptors in your lungs are found in the membranes of neuroendocrine cells. Scientists say these lung odor receptors can trigger the flask-shaped neuroendocrine cells to dump hormones that make your airways constrict. The receptors are called pulmonary neuroendocrine cells, or PNECs. Oversensitivity of PNECs may be linked to respiratory diseases, such as chronic obstructive pulmonary disease (COPD) and asthma.

PNECS were found by a team led by Yehuda Ben-Sharar, PhD, assistant professor of biology and medicine at Washington University in St. Louis, and including colleagues Steven L. Brody and Michael J. Holtzman of the Washington University School of Medicine, and Michel J. Welsh of the Lucille A. Carver College of Medicine at the University of Iowa.

Ben-Shahar says in a statement, "When people with airway disease have pathological responses to odors, they're usually pretty fast and violent. Patients suddenly shut down and can't breath and these cells may explain why."

The airway odor receptor cells may carry more than one receptor. They do not send nerve impulses to your brain. Instead they flood local nerves and muscles with serotonin and neuropeptides.

Ben-Shaher also says, "They are possibly designed to elicit a rapid, physiological response if you inhale something that is bad for you."

The odor receptors on the cells could be a potential target for new drugs. Blocking some of them might help prevent some attacks. When scientists looked at the airway tissues from patients with COPD they discovered more of these neurosecretory cells than airway tissues from healthy donors. Scientists say developing drugs that block PNECs will not be easy as lungs from different mammalian species tend to be very different. Tests on common lab subjects like mice may not be much help in developing drugs that work on human lungs.

The research was published in the American Journal of Respiratory Cell and Molecular Biology.

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