Chapter 15 - Neurotransmitters

Abstract

The study of neurotransmitters in parasitic nematodes is encouraged by the need for the development of novel anti-nematodal drugs and a requirement for an understanding of the mode of action of these drugs. The chapter focuses that the study of neurotransmitters and the study of anthelmintics are therefore interconnected. An early illustration of this connection is the discovery of the action of the inhibitory neurotransmitter GABA and the effect of the anthelmintic piperazine in Ascaris. The neurotransmitters considered in this chapter are, acetylcholine, GABA, L-glutamate, 5-HT, dopamine, NO and FMRFamide peptides. The chapter introduces the anatomy and physiology of Ascaris suum as a basis for explaining the actions of the putative neurotransmitters. The study of the neurotransmitters in nematodes, is encouraged by interest in the mode of action of anthelmintics, an interest in the mechanisms of anthelmintic resistance and also a desire to find new sites of action for novel drugs. The chapter examines neurotransmitters of nematodes with an emphasis on their site of action (receptor sites) and effects of related anthelmintic drugs.