MODULATION OF MIGRATION OF OESOPHAGOSTOMUM-DENTATUM LARVAE BY INHIBITORS AND PRODUCTS OF EICOSANOID METABOLISM

The effects of eicosanoids and of inhibitors of eicosanoid synthesis o n the migration of third-stage larvae (L3) of Oesophagostomum dentatum were studied in an in vitro migration assay procedure. The L3 were in cubated with diethylcarbamazine (DEC), indomethacin (INDO) or acetylsa licylic acid (ASA). Incubation with these inhibitors of eicosanoid met abolism resulted in a dose-dependent reversible inhibition of migratio n. The antimigratory effect of DEC could be completely reversed by tre atment of the L3 with the lipoxygenase (LOX)-products leukotriene (LT) B4 or LTC4. LTD4 had a less distinct but similar effect, while LTE4 f ailed to reverse migration inhibition. Treatment with combinations of cyclooxygenase (COX)-products (prostaglandin, PG) partially restored t he migration ability of ASA-treated L3, while PGD2, PGE2, PGF2 alpha o r PGI2 exerted no distinct effect on ASA-treated L3 when given separat ely. The suppression of L3 migration by compounds that are known as an tagonists of eicosanoid synthesis and the stimulation of migration of inhibitor-treated L3 by simultaneous application of eicosanoids indica te that these lipid mediators may play a significant role in physiolog ical processes that interact with worm motility. (C) 1998 Australian S ociety for Parasitology. Published by Elsevier Science Ltd.