Positron Tomograph for Preclinical Research

该共享仪器申请要求部分支持购买位于密歇根大学回旋加速器/PET中心的用于临床前研究的替代位置层析成像仪。许多美国国立卫生研究院资助的研究人员需要确定正电子标记的放射性示踪剂在实验动物中的生物分布。目前，回旋加速器/PET设备使用的是一台专用的、已有18年历史的动物PET，现在已经无法使用。这项拨款要求用一种现代的、功能性的扫描仪取代现有的层析成像仪，这种扫描仪能够成像灵长类动物的大脑，以及其他具有高解剖分辨率和良好灵敏度的小动物。拟议的替代层析成像仪不仅将允许正在进行的nih支持的研究继续进行，而且将促进放射性示踪剂生物医学成像新兴领域的新项目和用户的发展。临床前PET成像的一个主要用途是开发和表征新的放射性示踪剂。在小动物模型（通常是啮齿动物）的初始生物分布研究之后，在将新的示踪剂扩展到人类临床研究之前，进行体内灵长类动物成像研究以验证放射性示踪剂和所选分析方法的适用性。这将继续是替代层析成像仪的基本研究功能。层析成像应用的第二个主要领域涉及神经、心脏和肿瘤疾病动物模型的针对性研究。利用PET非侵入性测定放射性示踪剂分布的能力允许纵向实验方案的设计。与采用侵入性示踪剂分布的侵入性措施的设计相比，这大大减少了所需的动物数量，对于预期显著的个体间变异性的实验（例如：一些实验病变模型，基因转染研究等）或对动物有相当大投资的实验（例如灵长类动物研究）尤其重要。

This application for shared instrumentation requests partial support for the purchase of a replacement position tomograph for preclinical research to be located in The University of Michigan Cyclotron/PET Center. A number of NIH-funded investigators have research needs for determining the biodistribution of a positron-labeled radiotracers in experimental animals. At present, the Cyclotron/PET facility makes use of a dedicated, 18-year old animal PET that has now become unserviceable. This grant requests funds to replace the existing tomograph with a modern, functional scanner capable of imaging primate brain as well as well as other small animals with high anatomic resolution and good sensitivity. The proposed replacement tomograph will permit not only the continuation of ongoing NIH-supported research, but will facilitate the development of new projects and users in emerging areas of radiotracer biomedical imaging. A major prior use of preclinical PET imaging was in the development and characterization of novel radiotracers. After initial biodistribution studies in small animal models (usually rodents), in vivo primate imaging studies are performed to verify the suitability of the radiotracer and the chosen analytical approach before extending the new tracer to human clinical studies. This will continue to be an essential research function served by the replacement tomograph. A second major area of tomograph utilization involves targeted research in animal models of neurological, cardiac and oncological disorders. The ability to determine radiotracer distributions non-invasively with PET permits the design of longitudinal experimental protocols. This considerably reduces the numbers of animals needed in comparison to designs employing invasive invasive measures of tracer distribution, and is particularly essential to experiments where significant inter-individual variability is expected (e.g.: some experimental lesion models, gene transfection studies, etc.) Or where there is considerable investment in the animals (e.g. primate studies).