Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2010-7-13
pubmed:abstractText
Cannabinoid withdrawal produces a hypofunction of mesencephalic dopamine neurons that impinge upon medium spiny neurons (MSN) of the forebrain. After chronic treatment with two structurally different cannabinoid agonists, Delta(9)-tetrahydrocannabinol and CP55 940 (CP) rats were withdrawn spontaneously and pharmacologically with the CB1 antagonist SR141716A (SR). In these two conditions, evaluation of tyrosine hydroxylase (TH)-positive neurons revealed significant morphometrical reductions in the ventrotegmental area but not substantia nigra pars compacta of withdrawn rats. Similarly, confocal analysis of Golgi-Cox-stained sections of the nucleus accumbens revealed a decrease in the shell, but not the core, of the spines' density of withdrawn rats. Administration of the CB1 antagonist SR to control rats, provoked structural abnormalities reminiscent of those observed in withdrawal conditions and support the regulatory role of cannabinoids in neurogenesis, axonal growth and synaptogenesis by acting as eu-proliferative signals through the CB1 receptors. Further, these measures were incorporated into a realistic computational model that predicts a strong reduction in the excitability of morphologically altered MSN, yielding a significant reduction in action potential output. These pieces of evidence support the tenet that withdrawal from addictive compounds alters functioning of the mesolimbic system and provide direct morphological evidence for functional abnormalities associated with cannabinoid dependence at the level of dopaminergic neurons and their postsynaptic counterpart and are coherent with recent hypothesis underscoring a hypodopaminergic state as a distinctive feature of the 'addicted brain'.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1369-1600
pubmed:author
pubmed:issnType
Electronic
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
266-76
pubmed:meshHeading
pubmed-meshheading:20477755-Animals, pubmed-meshheading:20477755-Axons, pubmed-meshheading:20477755-Cannabinoids, pubmed-meshheading:20477755-Dopamine, pubmed-meshheading:20477755-Limbic System, pubmed-meshheading:20477755-Male, pubmed-meshheading:20477755-Marijuana Abuse, pubmed-meshheading:20477755-Mesencephalon, pubmed-meshheading:20477755-Neural Pathways, pubmed-meshheading:20477755-Neurogenesis, pubmed-meshheading:20477755-Neuronal Plasticity, pubmed-meshheading:20477755-Neurons, pubmed-meshheading:20477755-Piperidines, pubmed-meshheading:20477755-Pyrazoles, pubmed-meshheading:20477755-Rats, pubmed-meshheading:20477755-Rats, Sprague-Dawley, pubmed-meshheading:20477755-Receptor, Cannabinoid, CB1, pubmed-meshheading:20477755-Substance Withdrawal Syndrome, pubmed-meshheading:20477755-Substantia Nigra, pubmed-meshheading:20477755-Synapses, pubmed-meshheading:20477755-Tyrosine 3-Monooxygenase, pubmed-meshheading:20477755-Ventral Tegmental Area
pubmed:year
2010
pubmed:articleTitle
Altered architecture and functional consequences of the mesolimbic dopamine system in cannabis dependence.
pubmed:affiliation
Department of Animal Biology and Ecology, University of Cagliari, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't