title: Steroid biosynthesis within the frog brain: a model of neuroendocrine regulation.
abstract: There is now clear evidence that the brain, similar to the adrenal gland, gonads, and placenta, is a steroidogenic organ. Notably in the frog brain, the presence of various steroidogenic enzymes has been detected by immunohistochemistry in specific populations of neurons and/or glial cells. These steroidogenic enzymes are biologically active, as shown by the ability of brain tissue explants to convert [(3)H]pregnenolone into various radiolabeled steroids. The frog brain has also been extensively used as a model to study the mechanism of regulation of neurosteroidogenesis by neurotransmitters and neuropeptides. It has been demonstrated that the biosynthesis of neurosteroids is inhibited by gamma-aminobutyric acid (GABA), acting through GABA(A) receptors, and neuropeptide Y, acting through Y1 receptors, and is stimulated by the octadecaneuropeptide (ODN), acting through central-type benzodiazepine receptors, triakontatetraneuropeptide (TTN), acting through peripheral-type benzodiazepine receptors, and vasotocin, acting through V1a-like receptors. These data indicate that some of the neurophysiological effects of neurotransmitters and neuropeptides may be mediated through modulation of neurosteroid biosynthesis.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale, U413, Mont-Saint-Aignan, France.
authors.forename: Jean-Luc
authors.initials: JL
authors.lastname: Do Rego
authors.forename: Jae Young
authors.initials: JY
authors.lastname: Seong
authors.forename: Delphine
authors.initials: D
authors.lastname: Burel
authors.forename: Van
authors.initials: V
authors.lastname: Luu-The
authors.forename: Dan
authors.initials: D
authors.lastname: Larhammar
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Tsutsui
authors.forename: Georges
authors.initials: G
authors.lastname: Pelletier
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Tonon
authors.forename: Hubert
authors.initials: H
authors.lastname: Vaudry
mesh_terms: D000818:Animals; D001001:Anura / Q000378:metabolism*; D001921:Brain / Q000378:metabolism*; D006801:Humans; D008954:Models, Biological; D009490:Neurosecretory Systems / Q000378:metabolism*; D013256:Steroids / Q000096:biosynthesis*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D013256:Steroids; D005680:gamma-Aminobutyric Acid