prostaglandin

prostaglandiini puhekieltä Any of a group of naturally occurring lipids derived from the C20 acid prostanoic acid; they have a number of physiological functions and may be considered to be hormones.
2001, Leslie Iversen, Drugs: A Very Short Introduction (Oxford 2001), page 51:

This enzyme generates an inflammatory mediator known as prostaglandin, which triggers pain and other aspects of inflammation.