Functions of Histamines in the Defense of the Body
There are special cells in the nose called Mast cells which gets alerted whenever there is a presence of any irritants whether they are infectious types like bacteria or viruses or allergens. These mast cells will release granules which contains histamines and enzymes called tryptase. The tryptase make mucus thinner. Histamine has four-fold use at the back of the nose:
- It opens up blood vessels in the nose to allow water from the blood vessel to percolate into the nasal cavity, for effective washing of the cavity.
- It generates more sticky mucus to trap more of the pollutants.
- It causes irritation in the nose which makes us to sneeze. Sneezing is basically the act of bellowing out air from the nose
- It protects lungs from the pollutants by causing brancho-constriction.
- Coming out of fluid or plasma from under the surface cells in the nasal passages.
The fluid which is excreted from the nasal mucosa literally lifts up or displace the sticky mucus and wash it out by dislodging it from its place. The role played by the histamine was searched out by a Swedish doctor, and according to him this process is a part of the normal defense mechanism. According to a biologist named Margie Profet who has researched about allergies, the defense mechanism of our body helps us to remain healthy.
Though the histamines and the congestion each have unique role in the defense and repairing mechanism of our body the antihistamine and decongestant drugs help in ameliorating the symptoms of cold and runny nose. These drugs became easily available in the early 70s where they were available without a proper prescription. Though these drugs are widely used but they essentially block the defensive and repairing system in our body. Without allergic reaction or sneezing, the irritant materials get a chance to remain in the body and harm it.