How Taste Receptors in the Airway Protect Against Inhalation of Toxic Substances
Taste receptors, also known as taste buds, serve many distinct purposes. First and foremost, taste receptors serve as tools that help guard the body against ingestion of toxic substances. Most people assume that their taste receptors or taste buds are merely in place to serve them. After all, our taste buds let people know what foods “taste” good and which do not. Taste receptors are often overlooked however, as they serve many unique purposes.
Taste Receptor Mechanisms
Taste buds work by using special receptor cells that are capable of detecting whether substances we place near our mouth are nutritionally important or potentially toxic to the body. Taste receptors can also help regulate human digestive processes. Taste receptors are capable of sending messages to the brain that inform us of whether something is potentially sour or bitter.
Why is this important? It may prevent people from consuming something that is potentially toxic, including substances with high acid content. Taste receptors encourage the consumption of sweet and salty foods, which often contain an ample supply of carbohydrates and amino acids, which are useful to the human body and help promote growth.
The taste buds themselves are groups are epithelial cells. In recent years scientists have discovered that within the taste buds are taste receptors, known as G protein-coupled receptors or GPCR’s. These help regulate the way that humans taste various foods. The taste buds are not solely responsible for our perception of foods however.
There are many other channels and receptors expressed throughout the body including in the alimentary tract and throughout the respiratory passage. That is why people sometimes smell something and recognize its toxicity before they taste it.
Taste is comprised of many different categories:
Sweet Salty Sour Bitter Umami (this is defined as the taste of glutamate, a kind of sweet sensation).
Receptors in the kidney help regulate salty and sour tastes. Sweet and umami are regulated by taste receptors that have been identified as T1R and T2R. Believe it or not, throughout the body, in fact throughout many organ systems, taste receptors exist to help prevent toxic materials from entering the body. While most people assume taste is limited to the mouth and taste buds, this is a fallacy.
The stomach for example, contains receptors and various G-protein cells as does the large intestine. These largely serve as digestive functions, so that nutritious elements can be absorbed into the body, and toxic substances can be eliminated from the body. There are many receptors that detect micronutrients in the body. Certain receptors seek out only those micronutrients that promote survival, including carbohydrates which are an energy source. Others, which serve no function, will be eliminated.
As you can see, the body is a complex organism capable of amazing feats, with various signaling components or taste receptors located throughout its complex system. This beautiful system works synergistically to ensure that humans get the micronutrients they need, and expel toxic substances that would otherwise harm them. What an amazing vehicle the body is!
Finger, T.E. & Kinnamon, S.E. 2011. Taste isn’t just for buds anymore. F1000. Anschutz Medical Campus, University of CO Denver School of Medicine.