PT  - JOURNAL ARTICLE
AU  - Van Laere, Koen
AU  - Goffin, Karolien
AU  - Casteels, Cindy
AU  - Mortelmans, Luc
AU  - de Hoon, Jan
AU  - Bormans, Guy
AU  - Pieters, Guido
TI  - In vivo PET of cerebral cannabinoid-1 receptor availability is inversely correlated to novelty seeking in healthy human volunteers
DP  - 2007 May 01
TA  - Journal of Nuclear Medicine
PG  - 110P--110P
VI  - 48
IP  - supplement 2
4099  - http://jnm.snmjournals.org/content/48/supplement_2/110P.2.short
4100  - http://jnm.snmjournals.org/content/48/supplement_2/110P.2.full
SO  - J Nucl Med2007 May 01; 48
AB  - 372 Objectives: Neurochemistry may account for personality traits as a variance of behavioural patterns among individuals, as has been demonstrated for the dopamine and serotonin system by genetic and neuroimaging studies. The cerebral cannabinoid-1 receptor (CB1R) is an ubiquitous G-protein coupled receptor which presynaptically modulates other neurotransmitters. We have correlated regional CB1R availability, using a novel high-affinity and subtype-selective PET radioligand [18F]-MK9470. with the temperament dimensions of Cloninger's Temperament and Character Inventory (TCI). Methods: 47 healthy volunteers (23 M/24 F, age range 18-69 years) were investigated by [18F]-MK9470 PET. Parametric images of CB1R availability were determined by an area-under-the-curve model. Images were analyzed on a voxel-basis by statistical parametric mapping (SPM2). TCI scores (240 item) were normalized and converted into Z-scores as input for partial correlation calculations, correcting for age and gender effects. Results: Novelty seeking was inversely correlated to global CB1R availability (p=0.003, corrected for multiple comparisons). The subdimension “extravagance” showed a highly significant inverse correlation to CB1R availability (p<0.0001), especially in the amygdala, anterior cingulate, bilateral parietal cortex and precuneus. Also “disorderliness” was inversely correlated to global CB1R availability (p<0.0001). Conclusions: Low CB1R availability correlates to some items of the 240 item TCI personality scores. These findings suggest a potential role for the CB1R in behaviour. Further investigation of the relationships between the monoamine and cannabinoid systems may increase understanding of the neurochemical and neuroanatomical interactions that underlie these traits. Research Support (if any): Research Council of the K.U.Leuven (OT/05/58), the Flemish Fund for Scientific Research (FWO/G.0548.06)