Neuropeptides in Nematodes: Presence, Localization, and Effect on Locomotor Behavior

The investigations of the presence and distribution of neuropeptides in free-living and parasitic nematodes from various systematic groups have begun in the late 1980s. As a result of numerous studies, the family of FMRFamide-like peptides (FLPs) or FMRFamide-relative peptides (FaRPs) has been identi-fied. FLPs are relatively short peptides (typically < 20 amino acids) ending with a carboxyterminal RFamide motif. FMRFamide-like peptides are one of the largest and most diverse neuropeptide families, which members demonstrate the structural conservatism within all types of animals, including Nemathel-minthes (class Nematoda). It has been shown that many FMRFamide-like neuropeptides in free-living and parasitic species have a high level of structural conservatism, which does not depend on their life cycle, thereby suggesting that FLPs perform important biological functions in nematodes. The literature review is dedicated to analysis of the action of some relatively short FMRFamide-like neuropeptides isolated from free-living and zooparasitic nematodes on the locomotor behavior of the nematode Ascaris suum. Possible application of nematode FLPs or their synthetic structural analogs as anthelminthic drugs is discussed