WHAT CAN WE LEARN FROM PROSTAGLANDINS AND RELATED EICOSANOIDS IN INSECTS

Eicosanoids are oxygenated metabolites of three C20 polyunsaturated fa tty acids (20:3n-6, 20:4n-6, and 20:5n-3), While eicosanoids are very well known in mammalian systems, mostly due to their pharmaceutical in terest, there is increasing recognition of the significance of these c ompounds in insects and other invertebrates, In this paper we consider four major concepts emerging from work on eicosanoids in invertebrate s, First, the biological significance of eicosanoids extends far beyon d their physiological and pathophysiological actions in human and vete rinary medicine, Second, we can greatly improve our understanding of e icosanoids in insects by integrating our work on insects into ongoing studies of other invertebrates, Third, some eicosanoid actions may be fundamental to animals, Fourth, the biochemistry of eicosanoids in ins ects and other invertebrates can differ from expectations based on the mammalian background, Finally, we point to an uncharted frontier in i nsect studies-the biochemical mechanisms of eicosanoid action-by drawi ng attention to some of the work on eicosanoid receptors in mammalian systems.