The Nobel Prize in Physiology or Medicine for 1982 will be awarded to Sune Bergstrom, Bengt Samuelsson, and John Vane for their" discoveries con-cerning prostaglandins and related biologically active substances." This group of compounds includes prostaglandin (PG) E2, PGF2a, PGD2, thromboxane A2, prostacyclin, and the leukotrienes. All are potent chemical transmitters of intercellular and intracellular signals that mediate a diversity of physiologic and pathologic functions. They allare formed from oxygenation of arachidonic acid, a 20-carbon polyunsaturated fatty acid.

The structures of these arachidonic acid metabolites differ considerably as do their actions. Given the diversity of their effects, specific cells are highly selective in the biotransformation of ara-chidonic acid, usually forming an oxy-genated metabolite that can be linked to a function of the cell. Thus, thrombox-ane A2, formed upon activation of plate-lets, is a potent stimulus for platelet aggregation and vasoconstriction, whereas endothelial cells produce pros-tacyclin which is a powerful inhibitor of platelet aggregation anda vasodilator. The leukotrienes and prostaglandin D2 are produced by basophils and mast cells, and participate in the allergic re-sponses that result from immunologic activation of these cells. Sune Bergstrom is recognized for his pioneering work on the isolation of the prostaglandins and the elucidation of their structures. Knowledge of the structures of the prostaglandins provided the key that opened this field of research. Sune Bergstrom, previously Professor and Chairman of Chemistry and later Rector of the Karolinska Institute in Stockholm, is now Chairman of the WHO Advisory Committee on Medical Research.