It’s pretty much conventional wisdom that the entire respiratory tract – from nose to bronchioles – acts essentially as a single unit. New research in China suggests otherwise.
Researchers developed a novel way to introduce allergens in the trachea of mice – at a point well past the nose, so that the nasal passages were not involved in the initial exposure. It’s well established that allergens introduced in the nose have effects downstream in the lungs – and that makes sense, since the lungs draw them down with an inspired air. But no one had really looked the opposite – if an allergen is introduced downstream from the nose, will there be allergic/inflammatory effects upstream? It turns out the answer is no!
So, most people with asthma also have rhinitis – you know, the stuffy, congested nose. But – not all asthmatic people have rhinitis. This new research was an important step in understanding why – and will help with development of therapies that account for the “separateness” of the nose and the lungs!
Read more here – http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4274473/