TY - JOUR T1 - High resolution imaging of brain serotonin 5-HT1b receptors with [C-11]P943 JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 209P LP - 209P VL - 49 IS - supplement 1 AU - Sunhee Kim AU - Jean-Dominique Gallezot AU - Alexander Neumeister AU - Beata Planeta-Wilson AU - Paul Maguire AU - Timothy Mccarthy AU - Henry Huang AU - Yu-shin Ding AU - Richard Carson Y1 - 2008/05/01 UR - http://jnm.snmjournals.org/content/49/supplement_1/209P.2.abstract N2 - 903 Objectives: The initial human in vivo 5-HT1b receptor distribution with the 5-HT1b receptor antagonist, [C-11] P943 has been shown previously (AMI 2007). This study compares binding potential (BP) estimates using different kinetic methods. Methods: After administering [C-11] P943 to 14 healthy subjects (specific activity 3.4+2.1 Ci/umole; injected activity 16+2 mCi), data were acquired on a HRRT scanner for 2 h. Motion correction, co-registration and spatial normalization were performed. Pixel-wise BP images were created by both SRTM2 (simplified reference tissue model) and MRTM2 (multilinear reference tissue model, t > 20 min) with cerebellum as a reference region. SRTM2 had previously been shown to underestimate high BP values. ROIs were applied 1) from a template (Anatomical Automatic Labeling (AAL)) including four cortical regions, and globus pallidus (GP), and 2) new ROIs defined with guidance from the average BP image for nucleus accumbens (NA), substantia nigra (SN). Results: Visual and quantitative analysis of the individual and averaged BP images showed high BP in GP(1.15 +0.25 SRTM2/1.72+0.33 MRTM2), NA (0.99+0.40/1.23+0.46) and SN (0.68+0.24/1.03+0.33). The cortex has the highest BP in visual cortex (0. 94 + 0.24/1.09+0.23) and frontal (0.73 + 0.19/0.84+0.23) areas. As predicted by previous time-activity curve analysis, there was a significant (p<0.05) increase in BP values using MRTM2, more significantly in structures with high BP. However, there was no increase in intersubject variability with MRTM2 compared to SRTM2. Conclusions: These results demonstrate MRTM2 can be used to assess 5-HT1B BP with [C-11]P943. Research Support: Pfizer Inc and The National Center of PTSD ER -