Linked Life Data

9622603

Source:http://linkedlifedata.com/resource/pubmed/id/9622603

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1998-8-19
pubmed:abstractText
Effects of methylcobalamin (methyl-B12), a putative drug for treating human circadian rhythm disorders, on the melatonin-induced circadian phase shifts were examined in the rat. An intraperitoneal injection of 1-100 microg/kg melatonin 2-h before the activity onset time (CT 10) induced phase advances of free-running activity rhythms in a dose-dependent manner (ED50=1.3 microg/kg). Injection of methyl-B12 (500 microg/kg) prior to melatonin (1 microg/kg) injection induced larger phase advances than saline preinjected controls, while the injection of methyl-B12 in combination with saline did not induce a phase advance. These results indicate amplification of melatonin-induced phase advances by methyl-B12. Pinealectomy abolished the phase alternating effect of methyl-B12, suggesting a site of action within the pineal gland. In fact, methyl-B12 significantly increased the content of melatonin in the pineal collected 2-h after activity onset (CT 14). In contrast, no difference in melatonin content was found at CT 10, indicating that the effect of methyl-B12 may be gated after the activity onset time when endogenous melatonin synthesis is known to increase. These results suggest that methyl-B12 amplifies melatonin-induced phase advances via an increase in melatonin synthesis during the early subjective night at a point downstream from the clock regulation.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0006-8993
pubmed:author
pubmed:copyrightInfo
Copyright 1998 Elsevier Science B.V. All rights reserved.
pubmed:issnType
Print
pubmed:day
8
pubmed:volume
795
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
98-104
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Methylcobalamin amplifies melatonin-induced circadian phase shifts by facilitation of melatonin synthesis in the rat pineal gland.
pubmed:affiliation
Advanced Research Center for Human Sciences, Waseda University, Saitama, Japan. msikeda@mn.waseda.ac.jp
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't