title: Decreased density of I2-imidazoline receptors in the postmortem brain of heroin addicts.
abstract: The aim of this study was to quantitate imidazoline receptors in postmortem brains of heroin addicts who died of an opiate overdose. The density of I2-imidazoline receptors ([3H]idazoxan binding in the presence of adrenaline) and the immunoreactivity of the related 29/30 kDa imidazoline receptor protein were decreased (39% and 28%, respectively) in the frontal cortex. The density of brain I2-imidazoline receptors was also decreased in heroin-dependent rats (27%). This novel finding indicates that opiate addiction induces down-regulation of I2-imidazoline receptors in astrocytes, and presumably down-regulation of the functions associated with these receptors.
authors.affiliation: Department de Biologia Fonamental i Ciències de la Salut, Universitat de les Illes Balears, Palma de Mallorca (Balears), Spain.
authors.forename: M
authors.initials: M
authors.lastname: Sastre
authors.forename: P
authors.initials: P
authors.lastname: Ventayol
authors.forename: J A
authors.initials: JA
authors.lastname: García-Sevilla
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D001923:Brain Chemistry / Q000187:drug effects*; D015536:Down-Regulation / Q000502:physiology; D005260:Female; D003932:Heroin / Q000506:poisoning; D006556:Heroin Dependence / Q000378:metabolism*; D006801:Humans; D019329:Idazoxan / Q000378:metabolism; D054755:Imidazoline Receptors; D015151:Immunoblotting; D066298:In Vitro Techniques; D007700:Kinetics; D008297:Male; D011869:Radioligand Assay; D051381:Rats; D017207:Rats, Sprague-Dawley; D011955:Receptors, Drug / Q000187:drug effects*; D014404:Tubulin / Q000378:metabolism
chemical_list: D054755:Imidazoline Receptors; D011955:Receptors, Drug; D014404:Tubulin; D003932:Heroin; D019329:Idazoxan