As a part of continuous research on the neurobiology of the cephalopods in general, and the neuroendocrine control of reproduction in Octopus vulgaris in particular, the presence, the molecular analysis and the effect of FMRFamide on the screening-pigment migration in the visual system have been analysed. FMRFamide immunoreactive fibres are present in the outer plexiform layer of the retina as well as in the plexiform zone of the deep retina. These fibres presumably come from optic and olfactory lobes. We isolated an incomplete Octopus FMRFamide cDNA which encodes an amino terminal truncated precursor containing several FMRFamide-related peptides (FaRPs) showing a high degree of identity with the FaRPs encoded in the precursor of Sepia officinalis, except for the presence of an Rpamide related peptide, present only in cnidarians. Finally, stimulation of isolated retina demonstrated that the effect of this tetrapeptide, coupled with dopamine, is the induction of an extreme adaptation of the retina to the light condition. This situation de facto inhibits sexual maturation. Our results on the effect of FMRFamide on the retina confirm the suggested hypothesis that this peptide plays an inhibitory role on the activity of optic gland.
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http://dx.doi.org/10.1016/j.peptides.2003.07.018 | DOI Listing |
PLoS One
January 2025
Department of Aqualife Medicine, Chonnam National University, Yeosu, Republic of Korea.
The present study describes the differentiation process of male germ cells in Octopus vulgaris, the morphology of sperm in the testis and spermatophore, and the sperm released after the spermatophoric reaction. During spermatogenesis, the male sperm cell gradually elongates from a round shape, with cytoplasm shifting toward the head and the acrosome forming. Additionally, in the spermatid stage, the flagellum develops within the posterior nuclear channel and extends outside the cytoplasm.
View Article and Find Full Text PDFAm J Physiol Endocrinol Metab
January 2025
Aquatic Biotechnology Laboratory, Instituto Investigaciones Marinas-CSIC, Vigo, Spain.
The common octopus () is a promising candidate for aquaculture diversification, particularly in Europe. As interest in octopus farming grows, animal welfare concerns arise. In bony vertebrates (teleosts and tetrapods), measurements of the levels of corticosterone or cortisol have been successfully used as indicators of stress and welfare.
View Article and Find Full Text PDFJ Parasitol
December 2024
Departamento de Biología Marina, Universidad Autónoma de Yucatán, C.P. 97100, Mérida, Yucatán, México.
Although harvest of Octopus maya (Mexican four-eyed octopus) is one of the most important fisheries in the Yucatan Peninsula, little is known about the parasites of these cephalopods and how they affect host physiological processes. We analyzed the spatio-temporal variation of infection of O. maya by the cestode larva Prochristianella sp.
View Article and Find Full Text PDFHeliyon
November 2024
Department of Marine Science, Faculty of Fisheries, Kasetsart University, Bangkok, 10900, Thailand.
This study aimed to analyze the growth parameters and age-length relationships of the sandbird octopus () along the coast of Chao Samran Beach, Phetchaburi Province, Thailand. This included determining reproductive stages, the gonadosomatic index, and size at first maturity. A total of 1436 specimens comprising 782 males and 654 females were collected using octopus traps during January to December 2021.
View Article and Find Full Text PDFComp Biochem Physiol Part D Genomics Proteomics
December 2024
Centro de Investigacion Cientifica y de Educacion Superior de Ensenada (CICESE), Carretera Tijuana-Ensenada No. 3918, Zona Playitas, Ensenada, Baja California CP 22860, Mexico. Electronic address:
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