Production of eicosanoids by the killifish gills and opercular epithelia and their effect on active transport of ions.
Gills and opercular epithelia of the killifish (Fundulus heteroclitus) homogenized and incubated with radiolabeled arachidonic acid were found to produce prostaglandins, leukotrienes, and hydroxyeicosatetraenoic acids. These metabolites were identified using thin-layer chromatography, autoradiography, reverse-phase high-performance liquid chromatography, and ultraviolet spectroscopy. Addition of glutathione and epinephrine to the incubation mixture caused a diminution in the production of most eicosanoids (cyclooxygenase and lipoxygenase products) whereas indomethacin decreased only the cyclooxygenase metabolites. The effects of eicosanoids on short-circuit and potential difference across opercular epithelia mounted in a Ussing-type chamber were examined. Prostaglandin E2 had an inhibitory effect on ion transport whereas the sulfidopeptide leukotrienes (LTC4, LTD4, and LTE4) had a stimulatory effect. These results indicate that gills and opercular epithelia have the capacity to synthesize eicosanoids and that some of these metabolites may play a role in the regulation of ion transport in the kill fish.
D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism* / Q000494:pharmacology; D001693:Biological Transport, Active / Q000187:drug effects; D003532:Cyprinodontiformes / Q000378:metabolism*; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D005260:Female; D005880:Gills / Q000378:metabolism*; D007695:Killifishes / Q000378:metabolism*; D008084:Lipoxygenase / Q000378:metabolism; D008297:Male; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D011453:Prostaglandins / Q000096:biosynthesis* / Q000494:pharmacology; D013189:SRS-A / Q000096:biosynthesis* / Q000494:pharmacology
D001095:Arachidonic Acids; D011453:Prostaglandins; D013189:SRS-A; D016718:Arachidonic Acid; D008084:Lipoxygenase; D011451:Prostaglandin-Endoperoxide Synthases