Indolealkylamines in the coordination of nematode behavioral activities

Abstract

Nematode movements result from spontaneous myogenic depolarizations, neuromuscular coordination, and localized hydrostatic changes. These components are integrated into activities which are mutually exclusive or interdependent. Nervous connection is not known between all the organ systems, and the pharynx and female tract are somewhat autonomous. This problem is discussed, as is the limitation of a theory involving only cholinergic transmission. Serotonin, 5-hydroxytryptophan (5HTP), and epinephrine were all found to induce rapid and prolonged contractions in the female vagina/vulva of Caenorhabditis elegans, Aphelenchus avenae, Panagrellus redivivus, and Oswaldocruzia filiformis. It also caused spicule extension in males of P. redivivus. The responses are fully described together with dose-response data and the effect of adult age. The potential significance of indolealkylamines in nematode behavioral coordination is discussed, together with the relevance of anthelmintic formulation and the basis of immunological rejection.