Focus on prostacyclin and its novel mimetics.

Prostacyclin (PGI2) has been traditionally regarded as an important regulator of haemostasis, mediating its effects through prostacyclin (IP) receptors coupled to adenylate cyclase. Recent evidence suggests, however, that IP receptor agonists can activate multiple signalling pathways via the same IP receptor. Moreover, IP receptor agonists have interesting actions outside of the cardiovascular system, even extending to the release of non-adrenergic non-cholinergic (NANC) transmitters from enteric neurones. Here, Helen Wise and Robert Jones highlight some of this new information on PGI2 and its receptors, describe the properties of some chemically novel PGI2 mimetics, and report on current therapeutic uses of PGI2.