title: Appetite regulating factors in dourado, Salminus brasiliensis: cDNA cloning and effects of fasting and feeding on gene expression.
abstract: The dourado, Salminus brasiliensis (Cuvier, 1816) is a freshwater piscivorous Characin native to South American rivers. Owing to the high quality of its flesh and its fast growth, it is the object of both capture fisheries and fish farming. However, very little is known about the endocrine regulation of feeding and metabolism of dourado. In this study, cDNAs for orexin, CART and CCK were isolated in dourado, and their mRNA tissue distributions examined. In order to assess the role of these peptides in the regulation of feeding of dourado, the effects of fasting and feeding on mRNA expression levels of orexin, CART and CCK in the brain as well as CCK in the intestine were assessed. Whereas orexin and CCK have widespread mRNA distributions in the brain and peripheral organs, CART seems to be mostly limited to the brain. Orexin brain expression increased with fasting and displayed periprandial changes, suggesting it is involved in both long- and short-term regulation of feeding and appetite. CART and CCK hypothalamic expressions were not affected by fasting, but displayed periprandial changes with post-feeding decreases, suggesting roles in short-term satiation. CCK expression in the anterior intestine was not affected by fasting and did not display periprandial changes. Overall, our results suggest that orexin, CART and CCK are involved in the physiology of feeding of dourado.
authors.affiliation: Department of Biology, Memorial University of Newfoundland, St. John's, NL A1B3X9, Canada; Department of Biochemistry, Memorial University of Newfoundland, St. John's, NL A1B3X9, Canada. Electronic address: hvolkoff@mun.ca.
authors.forename: Hélène
authors.initials: H
authors.lastname: Volkoff
authors.affiliation: Departamento de Zootecnia, Setor de Piscicultura, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, 13418-900 Piracicaba, SP, Brazil.
authors.forename: Rafael Estevan
authors.initials: RE
authors.lastname: Sabioni
authors.affiliation: Departamento de Zootecnia, Setor de Piscicultura, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, 13418-900 Piracicaba, SP, Brazil.
authors.forename: José Eurico Possebon
authors.initials: JEP
authors.lastname: Cyrino
mesh_terms: D000818:Animals; D001066:Appetite / Q000502:physiology*; D060126:Characidae / Q000235:genetics* / Q000502:physiology*; D002766:Cholecystokinin / Q000235:genetics / Q000378:metabolism; D003001:Cloning, Molecular; D018076:DNA, Complementary / Q000235:genetics* / Q000378:metabolism; D005215:Fasting / Q000502:physiology*; D005247:Feeding Behavior / Q000502:physiology*; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D007031:Hypothalamus / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism; D000068797:Orexins / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D014018:Tissue Distribution; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein
chemical_list: D018076:DNA, Complementary; D009419:Nerve Tissue Proteins; D000068797:Orexins; D012333:RNA, Messenger; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein; D002766:Cholecystokinin
keywords: CART; CCK; Fasting; Feeding; Orexin; Salminus brasiliensis; mRNA expression