TY - JOUR
T1 - Interindividual variability and lateralization of μ-opioid receptors in the human brain
T2 - Individual differences in the μ-opioid receptor system
AU - Kantonen, Tatu
AU - Karjalainen, Tomi
AU - Isojärvi, Janne
AU - Nuutila, Pirjo
AU - Tuisku, Jouni
AU - Rinne, Juha
AU - Hietala, Jarmo
AU - Kaasinen, Valtteri
AU - Kalliokoski, Kari
AU - Scheinin, Harry
AU - Hirvonen, Jussi
AU - Vehtari, Aki
AU - Nummenmaa, Lauri
PY - 2020/8/15
Y1 - 2020/8/15
N2 - Alterations in the brain's μ-opioid receptor (MOR) system have been associated with several neuropsychiatric disorders. Central MOR availability also varies considerably in healthy individuals. Multiple epidemiological factors have been proposed to influence the MOR system, but due to small sample sizes the magnitude of their influence remains inconclusive. We compiled [11C]carfentanil positron emission tomography scans from 204 individuals with no neurologic or psychiatric disorders, and estimated the effects of sex, age, body mass index (BMI) and smoking on [11C]carfentanil binding potential using between-subject regression analysis. We also examined hemispheric differences in MOR availability. Older age was associated with increase in MOR availability in frontotemporal areas but decrease in amygdala, thalamus, and nucleus accumbens. The age-dependent increase was stronger in males. MOR availability was globally lowered in smokers but independent of BMI. Finally, MOR availability was higher in the right versus the left hemisphere. The presently observed variation in MOR availability may explain why some individuals are prone to develop MOR-linked pathological states, such as chronic pain or psychiatric disorders. Lateralized MOR system may reflect hemispheric work specialization in central emotion and pain processes.
AB - Alterations in the brain's μ-opioid receptor (MOR) system have been associated with several neuropsychiatric disorders. Central MOR availability also varies considerably in healthy individuals. Multiple epidemiological factors have been proposed to influence the MOR system, but due to small sample sizes the magnitude of their influence remains inconclusive. We compiled [11C]carfentanil positron emission tomography scans from 204 individuals with no neurologic or psychiatric disorders, and estimated the effects of sex, age, body mass index (BMI) and smoking on [11C]carfentanil binding potential using between-subject regression analysis. We also examined hemispheric differences in MOR availability. Older age was associated with increase in MOR availability in frontotemporal areas but decrease in amygdala, thalamus, and nucleus accumbens. The age-dependent increase was stronger in males. MOR availability was globally lowered in smokers but independent of BMI. Finally, MOR availability was higher in the right versus the left hemisphere. The presently observed variation in MOR availability may explain why some individuals are prone to develop MOR-linked pathological states, such as chronic pain or psychiatric disorders. Lateralized MOR system may reflect hemispheric work specialization in central emotion and pain processes.
KW - Ageing
KW - Brain lateralization
KW - Endogenous opioids
KW - Positron emission tomography
KW - [C]carfentanil
KW - μ-Opioid receptors
UR - http://www.scopus.com/inward/record.url?scp=85084978954&partnerID=8YFLogxK
U2 - 10.1016/j.neuroimage.2020.116922
DO - 10.1016/j.neuroimage.2020.116922
M3 - Article
C2 - 32407992
AN - SCOPUS:85084978954
SN - 1053-8119
VL - 217
JO - NeuroImage
JF - NeuroImage
M1 - 116922
ER -