title: [Opioid mechanisms for modulating pain: descending pathways. Critical review].
abstract: This paper presents an extensive review of contributions on opiate controlled descending projections modulating analgesia. While there is a quite definite agreement on the organisation and structure of these projections, their true physiological role remains quite dubious. The hypothesis so far formulated on the modalities of activation of these circuits apparently don't hold a critical re-examination.
mesh_terms: D000818:Animals; D002490:Central Nervous System / Q000503:physiopathology*; D004525:Efferent Pathways / Q000503:physiopathology; D004723:Endorphins / Q000502:physiology*; D008125:Locus Coeruleus / Q000503:physiopathology; D009020:Morphine; D009638:Norepinephrine / Q000502:physiology; D010146:Pain / Q000503:physiopathology*; D010487:Periaqueductal Gray / Q000503:physiopathology; D011903:Raphe Nuclei / Q000503:physiopathology; D051381:Rats; D012154:Reticular Formation / Q000503:physiopathology; D012701:Serotonin / Q000502:physiology; D009435:Synaptic Transmission
chemical_list: D004723:Endorphins; D012701:Serotonin; D009020:Morphine; D009638:Norepinephrine
vernacular_title: Meccanismi oppioidi di modulazione del dolore: i circuiti discendenti. Una revisione critica.