Prostaglandin similarity with hormones is in the effect they achieve by binding to the receptors. Their effects are mediated by paracrine or autocrine mechanisms. Another hormone characteristic is the ability to stimulate adenylate cyclase activity, producing cAMP as the second messenger.
On the other hand, prostaglandins differ from hormones in that they are not produced at a specific place but in many different places throughout the body. Also, the metabolic degradation of prostaglandins is very rapid.
