Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1995-8-24
pubmed:abstractText
Compelling evidence exists that tobacco-smoking represents a form of drug addiction to nicotine. Like several drugs of abuse, nicotine activates the mesolimbic dopamine system and this effect appears to be of critical importance for the reinforcing properties of the drug. Specifically, nicotine has been shown to increase burst activity in dopamine neurones of the ventral tegmental area, i.e. a mode of firing pattern in these cells which is physiologically associated with basic motivational processes underlying learning and cognitive behaviour. The stimulatory action of nicotine on mesolimbic dopamine neurones is exerted both at the somatodendritic and at the terminal levels. Yet, the release of dopamine in the nucleus accumbens induced by systemically administered nicotine is abolished by the nicotine receptor antagonist, mecamylamine when administered locally in the ventral tegmental area, but not in the nucleus accumbens. Whereas continuous infusion of nicotine into the ventral tegmental area produces a long-lasting increase in accumbal dopamine release, analogously to the effect of systemically administered nicotine, continuous infusion of nicotine into the nucleus accumbens produces a very short-lasting dopamine release. Thus, nicotinic receptors in the ventral tegmental area appear to be more significant than those located in the nucleus accumbens for mediating the stimulatory effect of nicotine on dopamine release in the nucleus accumbens. The effect of nicotine on midbrain dopamine systems may help to explain the extremely high prevalence of tobacco-smoking in schizophrenics, who frequently display so-called hypofrontality, i.e. a reduced functional activity in the prefrontal cortex which provides a direct input to the ventral tegmental area dopamine cells.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0901-9928
pubmed:author
pubmed:issnType
Print
pubmed:volume
76
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
157-62
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Nicotine dependence, midbrain dopamine systems and psychiatric disorders.
pubmed:affiliation
Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
pubmed:publicationType
Journal Article, Review, Research Support, Non-U.S. Gov't