PT  - JOURNAL ARTICLE
AU  - Matuskey, David
AU  - Park, Eunkyung
AU  - Nabulsi, Nabeel
AU  - Planeta, Beata
AU  - Esterlis, Irina
AU  - Williams, Wendol
AU  - D'Souza, Deepak Cyril
AU  - Huang, Yiyun
AU  - Morris, Evan
AU  - Carson, Richard
TI  - Age decline in the subcortical 5-HT6 receptor as imaged in male volunteers
DP  - 2013 May 01
TA  - Journal of Nuclear Medicine
PG  - 28--28
VI  - 54
IP  - supplement 2
4099  - http://jnm.snmjournals.org/content/54/supplement_2/28.short
4100  - http://jnm.snmjournals.org/content/54/supplement_2/28.full
SO  - J Nucl Med2013 May 01; 54
AB  - 28 Objectives Previous imaging studies have suggested an age-related decline in brain serotonin (5-hydroxytryptamine or 5-HT) measures in healthy subjects. This project seeks to investigate via positron emission tomography (PET) imaging whether the availability of 5-HT6 is also changed with age. Methods Twenty-nine healthy control subjects (all males; mean age 36±9; range 23-52 years) were scanned with the PET radiotracer [11C]GSK215083 that exhibits high binding affinity for the 5-HT6 receptor specifically localized in the striatum. Dynamic PET scans were acquired on the Siemens HR+. An early summed PET image was created and registered to the subject’s 3T MR anatomical image (6-parameter affine registration) which was then registered to an MR template using a non-linear transform with Bioimagesuite. Automatic regions-of-interest (Anatomical Automatic Labeling (AAL) for SPM2) were then applied to generate time-activity curves (TACs) in the striatum (caudate and putamen). The 90-min TACs were fitted with the MA1 (t*=40) model with a metabolite-corrected arterial input function, and regional binding potential (BPND) was calculated from the fitted VT values using the cerebellum as the reference region. Results Regional [11C]GSK215083 BPND displayed a negative correlation with age in the caudate (r = -0.51, P = 0.005) and putamen (r = -0.46, P = 0.01). 5-HT6 receptor availability in these two brain regions were found to be 22% (caudate) and 13% (putamen) lower with each decade of life studied. Conclusions PET imaging studies with [11C]GSK215083 infer an age-related decrease in 5-HT6 receptors in the striatum of healthy males. These findings indicate that age is a relevant factor to take into account when studying potential 5-HT6 receptor alterations in psychiatric disorders.