Preferred Label : nucleus raphe magnus;
Uberon definition : The nucleus raphe magnus, located directly rostral to the raphe obscurus, is afferently
stimulated from axons in the spinal cord and cerebellum. This makes the magnus a likely
candidate for part of the motor system; however, it seems to participate in the endogenous
analgesia system. The magnus receives descending afferents from the periaqueductal
gray, the paraventricular hypothalamic nucleus, central nucleus of the amygdala, lateral
hypothalamic area, parvocellular reticular nucleus and the prelimbic, infralimbic,
medial and lateral precentral cortices . All of these brain areas influence the main
function of the raphe magnus. The main function of the magnus is mostly pain mediation;
in fact it sends projections to the dorsal horn of the spinal cord to directly inhibit
pain. The periaquiductal gray, the epicenter of analgesia, sends efferent connections
to the nucleus raphe magnus in when it is stimulated by opiates (endogenous or otherwise).
Electrical stimulation of the PAG produces analgesia, as well as administration of
morphine to the PAG or n.r. magnus. The antinociceptic effects of electrical stimulation
of the PAG can be blocked by administering naloxone, an opiate antagonist, to the
n.r. magnus. All of this seems to indicate that the magnus is part of the endogenous
opiate system, and acts to inhibit pain in the spinal cord. [WP,unvetted].;
Uberon synonym : magnus raphe nucleus; raphe magnus nucleus;
Uberon related term : raphe magnus; red nucleus, magnocellular division; nucleus raphC) magnus;
Origin ID : 0002156;
UMLS CUI : C0175515;
Automatic exact mappings (from CISMeF team)
- Semantic type(s)
- UMLS correspondences (same concept)
- Uberon cross reference
- part of
The nucleus raphe magnus, located directly rostral to the raphe obscurus, is afferently
stimulated from axons in the spinal cord and cerebellum. This makes the magnus a likely
candidate for part of the motor system; however, it seems to participate in the endogenous
analgesia system. The magnus receives descending afferents from the periaqueductal
gray, the paraventricular hypothalamic nucleus, central nucleus of the amygdala, lateral
hypothalamic area, parvocellular reticular nucleus and the prelimbic, infralimbic,
medial and lateral precentral cortices . All of these brain areas influence the main
function of the raphe magnus. The main function of the magnus is mostly pain mediation;
in fact it sends projections to the dorsal horn of the spinal cord to directly inhibit
pain. The periaquiductal gray, the epicenter of analgesia, sends efferent connections
to the nucleus raphe magnus in when it is stimulated by opiates (endogenous or otherwise).
Electrical stimulation of the PAG produces analgesia, as well as administration of
morphine to the PAG or n.r. magnus. The antinociceptic effects of electrical stimulation
of the PAG can be blocked by administering naloxone, an opiate antagonist, to the
n.r. magnus. All of this seems to indicate that the magnus is part of the endogenous
opiate system, and acts to inhibit pain in the spinal cord. [WP,unvetted].
