Ponce de León Magdalena, Murgaš Matej, Silberbauer Leo R, Hacker Marcus, Gryglewski Gregor, Hahn Andreas, Lanzenberger Rupert
Department of Psychiatry and Psychotherapy, Medical University of Vienna, Austria; Comprehensive Center for Clinical Neurosciences and Mental Health, Medical University of Vienna, Austria.
Department of Biomedical Imaging and Image-guided Therapy, Division of Nuclear Medicine, Medical University of Vienna, Austria.
Neuroimage. 2025 May 1;311:121208. doi: 10.1016/j.neuroimage.2025.121208. Epub 2025 Apr 11.
Assessment of an antidepressant's occupancy at the serotonin transporter (SERT) in vivo using PET scans represents a demanding procedure. We evaluated novel approaches for SERT quantification to simplify the occupancy calculation. [C]DASB PET/MRI scans with bolus plus constant infusion were performed twice in 47 healthy controls and 31 patients with major depressive disorder with intravenous application of 8 mg citalopram or saline solution (randomized, cross-over, double-blind). Binding potentials (BP and BP) were estimated over time and within two radioligand equilibrium periods (before and after drug challenge). Reference occupancy was calculated as the relative decrease in post-drug BP between the placebo and citalopram scans. We introduced three methods for estimating SERT occupancy. Method 1 replaced the arterial blood sampling (BP) by reference region modeling during equilibrium timeframes (BP). Method 2 replaced the post-dose placebo equilibrium period with the pre-dose citalopram equilibrium period. Method 3 integrated aspects of both Methods 1 and 2, utilizing BP and the pre-dose citalopram equilibrium phase. The results showed equivalent occupancy values (p < 0.05) for the majority of VOIs and high agreement (max R = 0.89) between the reference (utilizing arterial blood sampling, along with the placebo and citalopram scan) and the proposed methods, indicating that they are a promising solution for simplifying occupancy estimation.
利用正电子发射断层扫描（PET）在体内评估抗抑郁药对血清素转运体（SERT）的占有率是一个要求很高的过程。我们评估了用于SERT定量的新方法，以简化占有率计算。对47名健康对照者和31名重度抑郁症患者进行了两次静脉注射8毫克西酞普兰或生理盐水（随机、交叉、双盲）的[C]DASB PET/MRI推注加持续输注扫描。随时间并在两个放射性配体平衡期（药物激发前后）内估计结合电位（BP和BP）。参考占有率计算为安慰剂和西酞普兰扫描之间药物后BP的相对下降。我们引入了三种估计SERT占有率的方法。方法1在平衡时间范围内（BP）通过参考区域建模取代动脉血采样（BP）。方法2用给药前西酞普兰平衡期取代给药后安慰剂平衡期。方法3整合了方法1和方法2的各个方面，利用BP和给药前西酞普兰平衡期。结果显示，大多数感兴趣区的占有率值相当（p < 0.05），参考方法（利用动脉血采样以及安慰剂和西酞普兰扫描）与所提出的方法之间具有高度一致性（最大R = 0.89），这表明它们是简化占有率估计的一种有前景的解决方案。
