Past research implicates eicosanoids, the phosphatidylinositol/protein kinase C system and proteolytic enzymes in fish ovulation. The proposal research will increase our understanding of the role of these three mediators in fish ovulation. Specifically, the production of lipoxygense metabolites by brook trout and goldfish ovaries will be investigated using radio labeled precursor incorporation, followed by metabolite separation on high performance liquid chromatography. The production of primary prostaglandins during steroid-induced ovulation in yellow perch will be investigated using radioimmunoassay. An incorporation system, involving the labeling of follicular phosphatidylinositol by radioactive myoinositol, will be investigated so that future research can use this system to study the cycling of follicular inositol phosphates following agonist stimulation. Total follicular proteolytic activity thoughout maturation and ovulation will be followed in brook trout and goldfish using substrate polyacrylamide gel electrophoresis. Collagenolytic activity will be followed through ovulation in brook trout follicles using a specific substrate assay to determine the role of this proteases in the release of the eggs from the follicles. The goal is a better understanding of the endocrine processes regulating ovulation in fish.