The pattern of neuropeptide F and RF-amide in two tapeworms

Abstract

Two years ago the first platyhelminth regulatory peptide, neuropeptide F (NPF), was isolated from the tapeworm Moniezia expansa by Maule et al. (1991) . NPF is a 39 amino acid peptide with a C terminal phenylalaninamide . NPF is the first platyhelminth neuropeptide to be sequenced fully . Preabsorption with NPF quenches the immunostaining with anti-FMRF-amide and anti-bovine PP (Halton et al. 1992) . As the first authentic flatworm neuropeptide, the occurrence and distribution of NPF along the whole flatworm line are under investigation. Both free-living and parasitic flatworms are being studied . So far NPF-immunoreactivity has been reported from three free-living flatworms (see Grahn et al., 1995) and from four parasitic flatworms (Marks et al., 1993) .FMRF-and RF-amide immunoreactive (IR) nerve cells and fibres are common in the gull-tapeworm Diphyllobothrium dendriticum . In order to test whether the patterns for NPF-and RF-immunoreactivity co-localize in the gull-tapeworm, immunostaining with anti-NPF and anti-RF were performed . To broaden the study, adult Proteochepalus exiguus from the intestine of whitefish were included in the experiment.