Monoaminergic mechanisms in the nervous system of Lumbricus terrestris (L.)

Studies on regeneration of central nervous system and social ability of the earthworm Eudrilus eugeniae

“…It is involved in a number of physiological functions and behaviors in both vertebrates and invertebrates (Welsh and Moorhead 1960). The distribution of the different monoaminergic neurons, such as serotonin, dopamine and others, has been described in the nervous system of annelids (Sporhase-Eichmann et al 1987;Leake et al 1985;Rude 1966;Myhrberg 1967;Rude et al 1969), and also the organization of the serotonergic system is studied in different earthworm species (Koza et al 2006;Sporhase-Eichmann et al 1987). The present investigation found the expression of 5-HT neurons in brain and the ventral nerve cord (Fig.…”

“…Most of the work focused on expression of acetylated tubulin (Muller and Henning 2004;Yoshida-Noro et al 2000), monoaminergic neurons (Myhrberg 1967;Ehinger and Myhrberg 1971;Koza et al 2006;Csoknya et al 2003), neuron-specific molecules, and structural restoration of the brain in the amputees. The regeneration kinetics and pattern formation of the brain varies among the species of earthworm.…”

The Neuronal Control of Locomotion in the Earthworm

“…I found that isolated nerve cords incubated with 14C-DA store it and convert a portion to 14C-NA which is also retainedin the nerve cord (unpublished), suggesting the presence of dopamine-/3-hydroxylase. Both the catecholamines and 5 H T may be catabolized by monoamine-oxidases as inhibitors of these enzymes increase the concentrations in the nerve cord (Myhrberg, 1967; Cashin, I 975) and sensitize isolated sections to exogenous monoamines (Bieger & Hornykiewicz, 1972a, b ;Gardner & Cashin, 1975). The greater increase in 5HT than in catecholamine concentration which we observed after a monoamine-oxidase inhibitor may indicate an alternative means of catabolism of NA and DA, perhaps by catechol-0-methyl transferase.…”

“…The r61e of the nerve cord in generating the rhythm of peristalsis has been put in doubt because isolated strips of body wall, in the absence of the nerve cord, contract rhythmically when exposed to 5-hydroxytryptamine (5HT) (Gardner & Cashin, 1975). This observation is significant in the light of the presence of 5HT in neurones in the ventral nerve cord (Rude, 1966; Myhrberg, 1967;Kerkut, Sedden & Walker, 1967), some of which send axons to the periphery (Myhrberg, 1967; Gardner, 1975).…”

“…As in other invertebrates (see Gerschenfeld, 1973) there are large amounts of 5HT (7-10,uglg) in the nerve cord (Welsh & Moorhead, 1960; Myhrberg & Rosengren, 1967; Rude, 1969). There are 5HT-containing cell bodies in the ventral nerve cord (Rude, 1969;Myhrberg, 1967;Kerkut et al, 1967; Gardner & Cashin, 1975) which could be interneurones (Rude, 1969; Myhrberg, 1972) or motoneurones (Rude, 1969; Myhrberg, 1967; Gardner, 1975) or both. Recent autoradiographic observations in Nereidae have shown uptake of 3H-5HT into neuromuscular junctions (Dhainaut-Courtois & Dhainaut, 1974).…”