title: Dehydroepiandrosterone regulates insulin-like growth factor-1 system in adult rat hypothalamus.
abstract: Dehydroepiandrosterone (DHEA) and its sulfate ester (DHEA-S) exert multiple effects in rodent and human brain. Several findings suggest that insulin-like growth factor-1 (IGF-1) is involved in the actions of DHEA. In this study, we assessed whether systemic administration of DHEA regulates the IGF-1 system in the hypothalamus, hippocampus, cerebral cortex, and cerebellum of adult rats. DHEA resulted in a significant reduction in IGF-1 receptor protein levels. This effect was dose dependent and restricted to the hypothalamus. In contrast to IGF-1 receptor, IGF-1-binding protein 2 levels were unaffected by DHEA treatment. IGF-1 levels were significantly increased in the hypothalamus of the rats treated with DHEA, whereas IGF-1 serum levels were not affected by DHEA. The effects of DHEA on the hypothalamic IGF-1 system may be highly relevant to the control and maintenance of hypothalamic neuroendocrine function.
authors.affiliation: Departamento de Fisiologia, ICBS, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil.
authors.forename: Maria Flavia
authors.initials: MF
authors.lastname: Ribeiro
authors.forename: Luis Miguel
authors.initials: LM
authors.lastname: Garcia-Segura
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002531:Cerebellum / Q000187:drug effects / Q000378:metabolism; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism; D003687:Dehydroepiandrosterone / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D007031:Hypothalamus / Q000187:drug effects* / Q000378:metabolism; D018971:Insulin-Like Growth Factor Binding Protein 2 / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000378:metabolism*; D008297:Male; D011863:Radioimmunoassay; D051381:Rats; D017208:Rats, Wistar; D017526:Receptor, IGF Type 1 / Q000378:metabolism
chemical_list: D018971:Insulin-Like Growth Factor Binding Protein 2; D003687:Dehydroepiandrosterone; D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1