What are 'prostaglandins'?

Prostaglandins are a group of biologically active compounds with a plethora of different actions and produced in virtually all tissues of the body. Unlike most autacoids (substances formed by cells themselves, which act as 'messengers' to other cells) they are not synthesized and stored ready for use. Rather, they are produced on demand in response to a great variety of stimuli. They have a major role in the mediation and modulation of inflammatory states - from the response set up around a splinter lodged in a finger to involvement in a major asthmatic attack or in anaphylactic shock. Many drugs which can be bought over the counter in pharmacies are anti-inflammatory agents, from lowly aspirin to many more modern remedies. All these so-called NSAIDs (non-steroidal anti-inflammatory drugs) have their effects by reducing or preventing the actions of prostaglandins. (World of the Body)