Trimethylamine-The Extracorporeal Envoy.

One of the most widespread and efficient mechanisms that has evolved to enable communication between discrete and spatially separate living organisms is the use of specific chemical messengers. The organoleptic properties of certain molecules, even at concentrations that do not necessarily evoke a conscious response, have been exploited to transmit information across relatively large distances. The trimethylated derivative of ammonia is one such molecule that is ideally suited to this function and several species are known to respond to its presence. This review uniquely collects together and integrates widely dispersed data to show that trimethylamine also may serve a communicatory role in man, with its influence extending outside of the body.