NICOTINE-ADDICTION SYMPOSIUM
The target articles below have been published, as part of an ongoing
workshop on nicotine addiction, in Psycoloquy, a refereed journal of
Open Peer Commentary sponsored by the American Psychological
Association (APA) and indexed in Current Contents and in PsycInfo
(
http://www.apa.org/psycinfo/about/covlist.html). Qualified
professional biobehavioral, neural or cognitive scientists are hereby
invited to submit Open Peer Commentary on one or more of these target
articles.
If you are not familiar with the format or acceptance criteria for
Psycoloquy commentaries (all submissions are refereed), please consult
the websites below or email for instructions:
SUBMIT COMMENTARIES TO: psyc(a)pucc.princeton.edu
URLs:
http://www.princeton.edu/~harnad/psyc.html
http://www.cogsci.soton.ac.uk/psyc
TARGET ARTICLES on which commentary is invited:
(1)
Balfour, D. (2001), The Role of Mesolimbic Dopamine in Nicotine
Dependence.
Psycoloquy 12(001)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.001
ABSTRACT: It is now widely accepted that a majority of habitual
tobacco smokers become addicted to the nicotine present in the
smoke. This brief review focuses on the evidence that nicotine
exerts on the mesolimbic dopamine (DA) system that are entirely
consistent with it having the properties of a psychostimulant drug
of abuse. Thus, the ability of nicotine to reinforce self-
administration in experimental animals depends upon its ability to
stimulate the DA-secreting neurones which project to the nucleus
accumbens. Microdialysis studies show that acute nicotine
preferentially stimulates DA overflow in the shell of the nucleus
accumbens, whereas subchronic nicotine causes sensitisation of its
stimulatory effects on DA overflow in the core of the structure.
The presentation discusses the evidence that stimulation of DA
overflow in the accumbens shell is required to elicit or, more
likely, signal the 'rewarding' properties of the drug which
reinforce self-administration. Based on the results of studies with
other psychostimulant drugs, it is possible that these effects are
mediated by the D-3 receptors that are found in relatively high
density in the subdivision of the structure. The sensitised effects
of subchronic nicotine in the core of the accumbens are thought to
mediate the transfer from 'drug-liking' to 'drug-seeking' behaviour
and, therefore, to be of fundamental importance to the development
of dependence. The nature of the receptor(s) involved remains to be
established although there is circumstantial evidence for a role of
both D-1 and D-2 receptors. Studies reported in more recent years
have suggested that increased DA overflow in the accumbens is not,
in itself, sufficient to account for the rewarding properties of
addictive drugs. The review concludes by discussing the evidence
that drugs of dependence preferentially increase DA overflow into
an extra-synaptic compartment where it gains access, by a process
of volume transmission, to extra-synaptic DA receptors located on
adjacent cells. These receptors, it is proposed, facilitate the way
in which we learn about cues associated with pleasurable stimuli
and the ways in which the may be experienced again.
(2)
Le Houezec, J. (2001), Non-Dopaminergic Pathways in Nicotine
Dependence.
Psycoloquy 12 (002)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.002
ABSTRACT: There is strong evidence that nicotine exerts its
positive reinforcing effects through the dopaminergic reward
system. However, recent literature has shown that nicotine can
modulate other neurotransmitter systems, mainly through
pre-synaptic cholinergic receptors. This paper focuses on some of
the systems that could participate in the nicotine dependence
process.
(3)
Oscarson, M. (2001), Nicotine Metabolism by the Polymorphic
Cytochrome P450 2A6 (CYP2A6) Enzyme: Implications for
Interindividual Differences in Smoking Behaviour. Psycoloquy 12
(003)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.003
ABSTRACT: Cytochrome P450 2A6 (CYP2A6) is one of the most important
enzymes in human nicotine metabolism. Genetic polymorphisms in the
CYP2A6 gene causes important interindividual variability in CYP2A6
activity and this variation can explain some of the interindividual
variability in nicotine metabolism previously reported. Here I
summarise the current knowledge about the CYP2A6 polymorphism, and
also discuss the potential importance of this polymorphism for
differences in smoking behaviour.
(4)
Sivilotti, L. (2001), Nicotinic Receptors: Molecular Issues.
Psycoloquy 12 (004)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.004
ABSTRACT: Expression of neuronal nicotinic receptors in Xenopus
oocytes has shown that several different subunit combinations are
functional, with a range of pharmacological and biophysical
properties. In the nervous system, nicotinic receptors are found on
the soma or the presynaptic terminals of neurones: the precise
molecular identification of these receptor subtypes remains a
challenge to pharmacology.
(5)
Smith, G. & Sachse, C. (2001), A Role for CYP2D6 in Nicotine
Metabolism? Psycoloquy 12 (005)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.005
ABSTRACT: Nicotine is known to be metabolised to its major
metabolite cotinine by members of the cytochrome P450 monooxygenase
superfamily. Although CYP2A6 has now been identified as the
principal enzyme which catalyses this biotransformation, CYP2D6 is
also an active nicotine C-oxidase. Some 8% of the Caucasian
population have reduced or absent CYP2A6 activity; CYP2D6 may play
a significant role in nicotine metabolism in these individuals.
CYP2D6 is highly polymorphic - a number of studies linking CYP2D6
genotype to smoking behaviour have now been published. CYP2D6 may
have an important constitutive function in neurotransmitter
metabolism and CYP2D6 genotype is thought to be a critical
determinant in the success of antidepressant drug treatment.
(6)
Wonnacott, S. (2001), Nicotinic Receptors in Relation to Nicotine
Addiction.
Psycoloquy 12 (006)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.006
ABSTRACT: The first step in processing nicotine's effects on the
brain is the drug's interaction with neuronal nicotinic receptors
(nAChR). The diversity of nAChR subtypes, their various modes of
response (activation, desensitisation, prolonged inactivation), and
the complex pharmacokinetics of nicotine delivery conspire to make
this a complex issue that is difficult to unravel. The alpha4beta2
nAChR subtype has the highest affinity for nicotine and is the
primary candidate for mediating nicotine's central effects. Chronic
nicotine exposure (in both humans, animals and cell culture
systems) leads to an increase in numbers of alpha4beta2 nAChR
(upregulation), with functional implications for withdrawal.
However, there is little evidence presently that nAChR upregulation
is pertinent to the induction or maintenance of dependence.
However, the particular characteristics of the alpha7 subtype of
nAChR suggest that it may participate in long term changes in
synaptic efficacy that could be relevant to nicotine dependence.
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Below is a list of other recently published PSYCOLOQUY target articles
that are also currently undergoing Open Peer Commentary. Commentary is
invited on these articles too:
INDIVIDUAL TARGET ARTICLES:
Navon, D. (2001), The Puzzle of Mirror Reversal: A View From
Clockland. Psycoloquy 12 (017)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.017
Kramer, D. & Moore, M. (2001), Gender Roles, Romantic Fiction and
Family Therapy. Psycoloquy 12 (024)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.024
Sherman, J. A. (2001), Evolutionary Origin of Bipolar Disorder
(EOBD). Psycoloquy 12 (028)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.028
Overgaard, M. (2001), The Role of Phenomenological Reports in
Experiments on Consciousness. Psycoloquy 12 (029)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.029
Crow, T. J. (2000) Did Homo Sapiens Speciate on the Y Chromosome?
Psycoloquy 11 (001)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?11.001
Margolis, H. (2000) Wason's Selection Task with A Reduced Array
Psycoloquy 11 (005)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?11.005
Place, U. T. (2000) The Role of the Hand in the Evolution of
Language Psycoloquy 11 (007)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?11.007
Green, C. D. (2000) Is AI the Right Method for Cognitive Science?
Psycoloquy 11 (061)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?11.061
Reifman, A. (2000) Revisiting the Bell Curve Psycoloquy 11 (099)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?11.099
MULTIPLE BOOK REVIEWS:
Ben-Ze'ev, A. (2001), The Subtlety of Emotions. Psycoloquy 12
(007)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.007
Miller, G. F. (2001), The Mating Mind: How Sexual Choice Shaped
the Evolution of Human Nature. Psycoloquy 12 (008)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.008
Zachar, P. (2001), Psychological Concepts and Biological
Psychiatry: A Philosophical Analysis. Psycoloquy 12 (023)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.023
Bolton, D. & Hill, J. (2001), Mind, Meaning & Mental Disorder: The
Nature of Causal Explanation in Psychology & Psychiatry.
Psycoloquy 12 (018)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.018
Praetorius, N. (2001), Principles of Cognition, Language and
Action: Essays on the Foundations of a Science of Psychology.
Psycoloquy 12 (027)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?12.027
Carstairs-McCarthy, A. (2000) The Origins of Complex Language
Psycoloquy 11 (082)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?11.082
Storfer, M. D. (2000) Myopia, Intelligence, and the Expanding Human
Neocortex Psycoloquy 11 (083)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?11.083
Tenopir, C. & King, D. W. (2000) Towards Electronic Journals:
Realities for Scientists, Librarians, and Publishers Psycoloquy 11
(084)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?11.084
Sheets-Johnston, M. (2000) The Primacy of Movement Psycoloquy 11
(098)
http://www.cogsci.soton.ac.uk/cgi/psyc/newpsy?11.098
SUBMIT COMMENTARIES TO: psyc(a)pucc.princeton.edu
URLs:
http://www.princeton.edu/~harnad/psyc.html
http://www.cogsci.soton.ac.uk/psyc