Allatostatin-like peptide in the brain-retrocerebral complex of the earwigLabidura riparia: cyclic variations related to the reproductive cycle

Citation
F. Sayah et al., Allatostatin-like peptide in the brain-retrocerebral complex of the earwigLabidura riparia: cyclic variations related to the reproductive cycle, INVERTEBR R, 34(2-3), 1998, pp. 269-275
Citations number
29
Categorie Soggetti
Animal Sciences","Animal & Plant Sciences
Journal title
INVERTEBRATE REPRODUCTION & DEVELOPMENT
ISSN journal
07924259 → ACNP
Volume
34
Issue
2-3
Year of publication
1998
Pages
269 - 275
Database
ISI
SICI code
0792-4259(199811)34:2-3<269:APITBC>2.0.ZU;2-A
Abstract
A polyclonal antibody raised against allatostatin-3 of Blattella germanica (BLAST-3) has been used to immunolocalize allatostatin-like peptides in the brain-retrocerebral complex of Labidura riparia adult females. Strongly st ained immunoreactive cells are observed in the pars intercerebralis (14 cel ls) and mainly in the pars lateralis (32 cells). Fibres leading to the corp us allatum are also stained. In the deutocerebrum, one cell is immunostaine d at the root of each antennal nerve. In the tritocerebrum two cells in eac h brain hemisphere are weakly immunostained. During the reproductive cycle, these cells and their axons show immunoreactivity at previtellogenic, ovul ation and ovarian arrest periods. During vitellogenesis, immunoreactivity i s restricted to only four perikarya in the pars intercerebralis. When young vitellogenic females are injected with 20-hydroxyecdysone (20E), which inhibits vitellogenesis, full immunoreactivity reappears, suggesting sensibility of these cells to 20E as is expected for a negative feed-back loop (Sayah et al., 1995). These results show that BLAST-3-like material is produced periodically in L abidura in correlation with low levels of juvenile hormone and the absence of vitellogenesis. This study contributes to provide information on the deg ree of homology of allatostatins across various insects.