On the Quantification of [18F]MPPF Binding to 5-HT1A Receptors in the Human Brain

[摘要] Previous studies have shown that 4-(2′-methoxyphenyl)-1-[2′-(N-2″-pyridinyl)-p-[18F]fluorobenzamido]ethylpiperazine ([18F]MPPF) binds with high selectivity to serotonin (5-HT1A) receptors in man. However, in these studies, the calculation of the binding potential (BP, which equals receptor density divided by equilibrium dissociation constant) used a metabolite-corrected arterial input. The aim of this study was to determine whether metabolite correction and arterial sampling are essential for the assessment of BP. Methods: Five analytic methods using full datasets obtained from 6 healthy volunteers were compared. In addition, the clinical applicability of these methods was appraised. Three methods were based on Logan analysis of the dynamic PET data using metabolite-corrected and uncorrected arterial plasma input and cerebellar input. The other 2 methods consisted of a simplified reference tissue model and standard compartmental modeling. Results: A high correlation was found between BP calculated with Logan analysis using the metabolite-corrected plasma input (used as the reference method for this study) and Logan analysis using either the uncorrected arterial plasma input (r2 = 0.95, slope = 0.85) or cerebellar input (r2 = 0.98, slope = 0.91). A high correlation was also found between our reference method and the simplified reference tissue model (r2 = 0.94, slope = 0.92). In contrast, a poor correlation was observed between our reference method and the standard compartmental model (r2 = 0.45, slope = 1.59). Conclusion: These results indicate that neither metabolite analysis nor arterial sampling is necessary for clinical evaluation of BP in the human brain with [18F]MPPF. Both the Logan analysis method with cerebellar input and the simplified reference tissue method can be applied clinically.

[学科分类] 医学（综合）

[关键词] serotonin receptor;binding potential;PET;modeling