1.6

Dopamine and opiate craving in the human brain: An imaging approach

Institution/
contact address:

Erasmus University Rotterdam, Department of Psychology
PO Box 1738, 3000DR Rotterdam

Tel.: (010) 408 95 63

Contactperson/
researcher(s):

I.H.A. Franken, W. van den Brink, J. Booij, G.J. Den Heeten, H. Schmidt, C.B.L.M. Majoie, V.M. Hendriks, E.J. Vlieger, & D. Dooijes.

Goal of the study:

The overall goal of the present study is to test the two-pathway model of craving (chronic vs. instant) in human opiate addicts and to study its neurobiological substrates. In order to examine the possible influence of pre-existing genetically determined individual differences in D2 receptor availability in the striatum, an A1 allele genotyping will also be conducted.

Type of study:

Experimental study.

Research
questions:

The overall objective of the study, the testing of the two-path craving model, can be divided into the testing of the hypotheses:

– Chronic opiate craving and anhedonia are significantly associated with a reduced availability of D2 receptors in the striatum and with decreased activity of the striato-orbitofrontal circuit.

– Availability of D2 receptors in the striatum is significantly correlated with pre-existing genotypal polymorphism of the A1 allele.

And:

– Instant opiate craving is associated with an increased cue-elicited endogenous dopamine release in the striatum and with increased activity of the nucleus accumbens.

Population
studied:

Abstinent male heroin dependent subjects.

Design and
instruments:

The relation between craving (using self-report) and D2 receptor availability will be studied using ligand [123I]iodobenzamide (IBZM) and single photon emission computed tomography (SPECT).

Genetic influences on D2 receptor availability will be studied by measuring the the presence of the A1 allele (a polymorphism in the noncoding region of the D2 receptor gene).

Endogenous dopamine release will be measured using [123I]IBZM SPECT technique.

Activation of neural correlates of heroin craving (frontal cortex and striatum) will be measured by using blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI).

Startdate:

December 2000.

Duration:

4 years.

Initiative:

I.H.A Franken & W. van den Brink.

Collaboration:

AMC Amsterdam.

Funding:

ZonMw Netherlands Organisation for Health Research and Development.

Results:

Not available yet.

Reporting:

Dissertation, & journal articles.