Date of Award
Nitric oxide, NO, is a molecule with great versatility and importance. Made up of only a single atom of nitrogen and a single atom of oxygen, nitric oxide is perhaps one of the smallest paramagnetic molecules found in nature. The functions of NO in the body are not all known, but this molecule definitely plays a variety of roles. It is involved in the regulation of blood pressure, and it sometimes acts as a messenger for cells as well as a killer of them. It also is important in the defense of the body against foreign invaders. The significance of chemistry to nitric oxide's effects in the body are nowhere more aptly demonstrated than by the British chemist Sir Humphry Davy (Lancaster 250). Davy, who discovered the notorious laughing gas (nitrous oxide, N20), nearly died when he inhaled a small amount of nitric oxide. Although structurally related, these two molecules have two very different physiological effects. Made up of only fifteen electrons, nitric oxide contains one unpaired electron, which contributes to a property called paramagnetism. Since electrons tend to pair, molecules with unpaired electrons are very rare because they are so reactive. Nitric oxide tends to react rapidly with other atoms or molecules with unpaired electrons. Among the molecules commonly present in cells, the most significant paramagnetic species are molecular oxygen (02), superoxide (02)" and various complexes of iron, copper, and manganese. Nitric oxide's reactions with molecular oxygen and metalloproteins dominate its chemistry and therefore its molecular actions in the cell.
Nitric oxide has many different functions in the human body. Many of these functions are beneficial, but some can be deadly. By finding out how nitric oxide binds to different enzymes and heme groups, one is able to get a better understanding of why it functions as it does in the human body. This could also provide scientists with information as to how to develop drugs that would turn the production of NO on and off.
The research on nitric oxide is relatively new. There are still many things that are unknown about this versatile molecule. Therefore, research on this particular molecule is of utmost importance when compared to another molecule such as 02 which has been researched thoroughly. Information from this research could contribute to a better understanding of the function of nitric oxide.
Braxton, Thomas M. Jr., "Synthesis of Nitrosyl Metallpoprphyrins" (1995). McCabe Thesis Collection. 15.