SYSTEMATIC REVIEW OF THE ROLE OF PROSTAGLANDINS

The prostanoids are part of a family of biologically active lipids derived from the action of cyclooxygenases or prostaglandin synthases upon the twenty"carbon essential fatty acids or eicosanoids. They can be further subdivided into th ree main groups, the prostaglandins, prostacyclins and thromboxanes , each of which is involved in some aspect of the Inflammatory response. The prostaglandins were first isolated fr om semen and named from the prostate gland, thought to be their source, as long ago as the 1930 s, but it was the 1960s before the biosynthetic relationship to specific essential fatty acids was described and intensive research into their biological properties began. The Nobel Prize for Me dicine for 1982 was given to Professors Bengt Samuelsson, John Vane and Sune Bergstrom for their discoveries in this field (see the review by Samuelsson cited below). In general, prostaglandins occur at very low levels in tissues, of the order of nanomolar concentrations, but they have profound biological activities. mostly used in drug in misoprostol,ripoprostol,enprostil and arbaprostil prostacylin all the prostaglandins analogous PGs present in human bronchi,cardiac musules lungus,menstrul fluid ,semen, stomuch mucosa ,vagus nerve, placenta blood vesseles bronchi,cardiac musules lungus,menstrul fluid ,semen, stomuch mucosa ,vagus nerve,placenta blood vesseles. They both sustain homeostatic functions and mediate pathogenic mechanisms, including the inflammatory response. They are generated from arachidonate by the action of cyclooxygenase (COX) isoenzymes and their biosynthesis is blocked by nonsteroidal antiinflammatory drugs (NSAIDs), including those selective for inhibition of COX-2.