Nitric oxide is a chemical compound generated naturally by humans and animals alike. It is one of the simplest compound gases, having only one nitrogen (N) and one oxygen (O) in its composition, giving it the chemical formula of NO. The colorless gas is also found in the air and comes from fossil fuel and automobile emissions and becomes a pollutant. In 1992, nitric oxide was named the “Molecule of the Year” because studies about the gas helped in the advancement of such fields like immunology, neuroscience, and physiology.
The discovery of nitric oxide is given much credit to Joseph Priestly, an English theologian and clergyman whose interest in the sciences also led him to discover oxygen. Priestly initially called the chemical compound “nitrous air” when he discovered it in 1772, and classified it as a toxic gas present in the air. It was more than two centuries later in 1987 when it was found out that the gas was naturally present in and was produced also by the human body.
One of the most important functions of nitric oxide in the body is to relay “messages” or signals among the cells to carry out certain processes. NO is especially important in regulating and supplying blood flow in certain body parts when needed. For example, when a person’s exposed arms are in need of blood to keep them warm, the blood vessels will give a signal to the NO, which will then pass the message to the muscles. In turn, the muscles will relax, causing the blood vessels to dilate and let in more blood. NO also helps the body decrease blood flow levels when it is at ease.
Bodybuilders have taken advantage of nitric oxide’s particular ability to increase blood flow by taking NO supplements, supposedly to supply more blood to the muscles and to make them bigger. Unfortunately, excessive amounts of NO become free radicals that can destroy the cells and cause more harm than good to the body. Studies have shown that NO can cause side effects such as diarrhea, nausea, and severe weakness. In worse cases, arrhythmia or an irregular heartbeat can also be experienced.
In moderate and prescribed amounts, nitric oxide is useful for patients suffering from hypertension and helps prevent clogged arteries. In 1989, it was also shown that cells called macrophages use the compound to destroy certain bacteria and malignant cells in the body. Nitric oxide has also been used for those experiencing erectile dysfunction.