ISSN:
1432-0878
Keywords:
Key words: Octopamine
;
Nervous system
;
central
;
Immunocytochemistry
;
Lumbricus terrestris (Annelida)
;
Eisenia fetida (Annelida)
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Abstract. The distribution of octopamine (OA)-like immunoreactive neurons was investigated, and the concentration of OA was assayed by high-performance liquid chromatography in the central nervous system of Oligochaeta species, Lumbricus terrestris, Eisenia fetida, and Lumbricus polyphemus. OA-like immunoreactive nerve cells were found in all parts of the central nervous system; certain regions of the neuropil of the ganglia were densely innervated by immunoreactive fibers. Altogether 96–102 OA-like immunoreactive neurons were detected in the cerebral ganglion, 18 in the subesophageal ganglion, and 14 in the segmental ganglia of 2nd–5th and 40th–45th body segments of Lumbricus terrestris; the relevant numbers of neurons in Eisenia were 88–98, 20–22, and 6, respectively. The sizes of OA immunoreactive-like cells showed great variability according to their anatomical localization. High-performance liquid chromatography assay revealed the presence of OA in each investigated part of the central nervous system, showing concentration values between 8.6 and 16.7 pmol/mg wet weight in the three species. The concentration of the OA precursor tyramine was significantly lower in the central nervous system of Eisenia (〈0.5 pmol/mg wet weight) than in that of both Lumbricus species (0.67–2.0 pmol/mg wet weight). The metabolism of 3H-tyrosine revealed that tyramine and OA were synthesized by the enzymes tyrosine-decarboxylase and tyramine-β-hydroxylase, respectively. Thus, OA appears to have a regulatory role in the central nervous system of Oligochaeta.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s004410050617
Permalink
