For instance, neurotransmitters are a class of short-range signaling molecules that travel across the tiny spaces between adjacent neurons or between neurons and muscle cells. Other signaling ...

Multidisciplinary strategies for visualizing intracellular signaling and intercellular communication: Immune cell-to-cell interactions are difficult to study because they undergo continuous structural ...

For a general summary overview ... Their very short half-lives means that they are very effective at signaling nearby cells, but fade fast enough to not have global body effects.