Establishment of a map of neurons in the brain of Eisenia fetida (Annelida, Oligochaeta) containing substances immunologically specific to vertebrate peptides

• Published in: General and comparative endocrinology Vol. 65; no. 3; pp. 457 - 468
• Main Authors: Lkhider, M, Marcel, R, Tramu, G
• Format: Journal Article
• Language: French
• Published: United States 01.03.1987
• Subjects: Animals; Brain - cytology; Corticotropin-Releasing Hormone - analysis; Dynorphins - analysis; Enkephalin, Leucine - analysis; Enkephalin, Methionine - analysis; Growth Hormone-Releasing Hormone - analysis; Histocytochemistry; Immunologic Tests; Neurons - analysis; Neurons - cytology; Neuropeptides - analysis; Oligochaeta - cytology; Serotonin - analysis; Sincalide - analysis; Substance P - analysis
• ISSN: 0016-6480; 1095-6840

Several antisera specific to neuropeptides of vertebrates were applied to sections of the earthworm Eisenia fetida Sav. Some of them were able to reveal specific neurones of the supraoesophageal ganglion: h-GHRF, CRF, Leu- and Met-enkephalin, dynorphin, substance P, CCK-8, and CCK-8S. A map of different areas or nuclei was established in the brain, taking position of reactive cells into account. Four symmetrically paired nuclei and one mediodorsal nucleus were identified and plotted. There is generally no characteristic modification correlated with maturation of the worms. However, the reaction against anti-Leu-enkephalin differs significantly according to age of Eisenia in nucleus No. 1 and particularly in nuclei No. 2 where one cell group presents specific reactivity on and after puberty. Moreover, the successive application of two antisera to the same sections after elution showed no coexistence of substances in a single neurone. By comparison with these vertebrate peptide-like containing nerve cells, the assay to anti-5-HT showed only a few reactive aminergic neurones. An attempt of correlation of cellular types with reactive perikarya is started.