Dataset Information

Imaging the cannabinoid CB1 receptor in humans with [11C]OMAR: assessment of kinetic analysis methods, test-retest reproducibility, and gender differences.

ABSTRACT: The Radiotracer [(11)C]OMAR was developed for positron emission tomography (PET) imaging of cannabinoid type-1 receptors (CB1R). The objectives of the present study were to evaluate kinetic analysis methods, determine test-retest reliability, and assess gender differences in receptor availability. Dynamic PET data were acquired in 10 human subjects, and analyzed with one-tissue (1T) and two-tissue (2T) compartment models and by the Logan and multilinear analysis (MA1) methods to estimate regional volume of distribution (VT). The 2T model inclusive of a vascular component (2TV) and MA1 were the preferred techniques. Test-retest reliability of VT was good (mean absolute deviation ~9%; intraclass correlation coefficient ~0.7). Tracer parent fraction in plasma was lower in women (P<0.0001). Cerebral uptake normalized by body weight and injected dose was higher in men by 17% (P<0.0001), but VT was significantly greater in women by 23% (P<0.0001). These findings show that [(11)C]OMAR binding can be reliably quantified by the 2T model or MA1 method and demonstrate the utility of this tracer for in vivo imaging of CB1R. In addition, results from the present study indicate that gender difference in receptor binding should be taken into consideration when [(11)C]OMAR is used to quantify CB1R availability in neuropsychiatric disorders.

SUBMITTER: Normandin MD

PROVIDER: S-EPMC4528005 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Imaging the cannabinoid CB1 receptor in humans with [11C]OMAR: assessment of kinetic analysis methods, test-retest reproducibility, and gender differences.

Normandin Marc D MD Zheng Ming-Qiang MQ Lin Kuo-Shyan KS Mason N Scott NS Lin Shu-Fei SF Ropchan Jim J Labaree David D Henry Shannan S Williams Wendol A WA Carson Richard E RE Neumeister Alexander A Huang Yiyun Y

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism 20150401 8

The Radiotracer [(11)C]OMAR was developed for positron emission tomography (PET) imaging of cannabinoid type-1 receptors (CB1R). The objectives of the present study were to evaluate kinetic analysis methods, determine test-retest reliability, and assess gender differences in receptor availability. Dynamic PET data were acquired in 10 human subjects, and analyzed with one-tissue (1T) and two-tissue (2T) compartment models and by the Logan and multilinear analysis (MA1) methods to estimate regiona ...[more]

PMID: 25833345

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Dataset Information

Imaging the cannabinoid CB1 receptor in humans with [11C]OMAR: assessment of kinetic analysis methods, test-retest reproducibility, and gender differences.

Publications

Imaging the cannabinoid CB1 receptor in humans with [11C]OMAR: assessment of kinetic analysis methods, test-retest reproducibility, and gender differences.

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