Gasotransmitters
Gaseous signaling molecules are gaseous molecules that are either synthesised internally (endogenously) in the organism, tissue or cell or are received by the organism, tissue or cell from outside (say, from the atmosphere or hydrosphere, as in the case of oxygen) and that are used to transmit chemical signals which induce certain physiological or biochemical changes in the organism, tissue or cell. The term is applied to, for example, oxygen, carbon dioxide, nitric oxide, carbon monoxide, hydrogen sulfide, sulfur dioxide, nitrous oxide, hydrogen cyanide, ammonia, methane, hydrogen, ethylene, etc.
Many, but not all, gaseous signaling molecules are called gasotransmitters.
The biological roles of each of the gaseous signaling molecules are in short outlined below.
Gasotransmitters is a subfamily of endogenous molecules of gases or gaseous signaling molecules, including NO, CO, H2S. These particular gases share many common features in their production and function but carry on their tasks in unique ways, which differ from classical signaling molecules, in the human body. In 1981, it was first suggested from clinical work with nitrous oxide that a gas had a direct action at pharmacological receptors and thereby acted as a neurotransmitter. In vitro experiments confirmed these observations which were replicated at NIDA later.
The terminology and characterization criteria of “gasotransmitter” were firstly introduced in 2002. For one gas molecule to be categorized as a gasotransmitters, all of the following criteria should be met.
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