Changes in the expression of PACAP-like compounds during the embryonic development of the earthworm Eisenia fetida.
J Mol Neurosci
; 36(1-3): 157-65, 2008 Nov.
Article
em En
| MEDLINE
| ID: mdl-18607777
ABSTRACT
Pituitary adenylate cyclase-activating polypeptide (PACAP) is expressed at very early stages in the vertebrate nervous system, and its functions in the embryonic development have been shown by various studies. PACAP is an extremely conserved molecule in phylogeny; however, little is known about its presence and functions in invertebrates. Our previous studies have shown the occurrence of PACAP-like immunoreactivity in the invertebrate nervous system. The aim of this study was to investigate the presence and localization of PACAP-like compounds during the embryonic development of earthworms from cocoon deposition to hatching using immunological methods (radioimmunoassay, dot blot, immunohistochemistry). PACAP-like immunoreactive compounds were detected at very early stages of the embryonic development of the earthworm Eisenia fetida. No significant changes were observed during the early stages in the developing embryo, but a marked increase occurred before hatching. In contrast, during the embryonic development, the level of PACAP-like compounds gradually decreased in cocoon fluids. Immunohistochemistry revealed the presence of PACAP-like immunoreactive cell bodies and processes in the developing body wall, prostomium, pharyngeal wall, and central nervous system. Cells located in the body wall correspond to putative progenitor cells of primary sensory cells. In the present study, we also showed that the clitellum (reproductive organ) of sexually mature worms contained significantly higher levels of PACAP-like immunoreactivity than other regions of the same animals or the clitellar region of a non-reproducing animal. In summary, these observations provide a morphological basis and suggest a role of PACAP(-like peptides) in the reproductive and developmental functions of invertebrates.
Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Oligoquetos
/
Polipeptídeo Hipofisário Ativador de Adenilato Ciclase
Limite:
Animals
Idioma:
En
Revista:
J Mol Neurosci
Assunto da revista:
BIOLOGIA MOLECULAR
/
NEUROLOGIA
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Hungria