正电子发射断层扫描术在兔眼神经受体成像的应用  

Application of positron emission tomography for imaging of neuroreceptor in rabbit eyes

作　　者：汪维芳[1] 盛敏杰[1] 林安娟[1] 顾真寰[1] 陈轶卉[1] 石渡喜一 

机构地区：[1]同济大学附属上海第十人民医院眼科,上海市200072 [2]日本东京老人综合研究所PET医疗中心,日本东京市173-0022

出　　处：《眼科新进展》2009年第7期514-518,共5页Recent Advances in Ophthalmology

基　　金：同济大学医科科技发展基金资助(编号:2006062)~~

摘　　要：目的采用正电子发射断层扫描术(positron emission tomography,PET)对家兔眼内的神经受体进行定量检测及成像。方法选择家兔16只随机分为4组(n=4),用PET来检测4种不同的神经受体:标记化合物[11C]raclopride测定多巴胺D2受体;[11C]CFT测定多巴胺载体;[18F]MPPF用于测定5-羟色胺受体;[11C]SA4503测定σ1受体。对每一组家兔在完成基线测定后,不改变体位,进行第2次测定。每组中的2只家兔在测定前注射拮抗剂进行预处理测定;另2只家兔在测定过程中注射拮抗剂进行置换测定。并且在PET测定后15min进行体外放射自显影术,比较二者的测定值。结果PET的基础测定中眼球组织和脑组织都成像,但眼球组织的放射能较脑组织中明显低下。除[18F]MPPF,预处理测定显示眼前段的摄取减少25%～28%。但是置换测定中,只有[11C]SA4503摄取减少了20%,[11C]raclopride有16%被阻断,[11C]CFT则没有明显变化。PET成像后的放射自显影术可以看出家兔眼内的神经受体主要聚集于视网膜和虹膜睫状体,且放射自显影术成像比PET成像信号清晰。结论在兔眼中PET中神经受体的结合率没有特异性。Objective To study the quantitative detection and imaging of neuro- receptors by positron emission tomography （PET） in rabbit eyes. Methods Sixteen rabbits were randomly divided into four groups,four rabbits in each group. PET imaging was performed to detect four neuroreceptors in eyes： [^11C ] raclopride for monitoring dopamine D： receptor, [^11C ] CFT for dopamine transporter, [^18 F] MPPF for 5-HTA and [^11C ] SA4503 for σ1 receptor, respectively. After the assessment of baseline conditions of each group, the secondary measurement was done at the same body position. Two rabbits of each group were injected antagonist before the secondary measurement to take pretreatment measurement,while the other two rabbits were injected antagonist during the secondary measurement to take displacement measurement. Measured values were compared between two different measurements. Autoradiography was performed at 15 minutes after PET measurement. Results In PET imaging, four radioligands outlined the eyes and brain in the baseline, but the radioactivity levels in eyes were much lower than those in the brain. Except for [^18F] MPPF,pretreatment resulted in a slight reduction （25% to 28% ） in uptake of [^11C ] raclopride, [^11C ] SA4503 and [^11C ]CFT in the anterior segment of eyes. In the displacement study, slightly lower （ 20% ） reduction was found in [^11C ]SA4503,16% reduction in [^11C ] raclopride, but no reduction in [^11C ]CFT,respectively. The binding of neuroreceptors in the iris-ciliary body and retina were confirmed by autoradiography. However, the autoradiography signal in eyes was clearer than the PET signal. Conclusion The identification of radioligand-neuroreceptor binding by PET in rabbit eyes is not specific enough.

关 键 词：正电子发射断层扫描术 受体 放射自显影术 预处理测定 替换测定 

分 类 号：Q959.836[生物学—动物学] R77[医药卫生—眼科]