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目的探讨脑多巴胺受体显像中作为纹状体非特异性摄取的参照区。方法用大鼠体内研究资料，比较额叶皮质和小脑作为纹状体非特异性摄取参照区所获得的纹状体特异性结合１２５Ｉ（ｓ）（－）３碘２羟基６甲氧基Ｎ〔（１乙基）２吡咯烷基）甲基〕苯甲酰胺（ＩＢＺＭ）的结果。结果碘标记ＩＢＺＭ呈立体选择性和可逆性地与纹状体多巴胺Ｄ２受体结合。额叶皮质和小脑显示对配体的快速摄取和洗脱。当用小脑摄取作为纹状体非特异性摄取参照时，未能获得ＩＢＺＭ的饱和性，而用额叶皮质作为参照区时，可证实其可饱和性，Ｂｍａｘ＝４４ｐｍｏｌ／ｇ纹状体组织。Ｈａｌｏｐｅｒｉｄｏｌ的置换率和由大剂量ｓｐｉｐｅｒｏｎｅ或ｈａｌｏｐｅｒｉｄｏｌ竞争性抑制实验衍变而来的纹状体和其他脑区之间摄取差值百分率均提示：小脑摄取低估了纹状体的非特异性摄取，额叶皮质是一个合适的纹状体非特异性摄取参照区。结论在纹状体多巴胺Ｄ２受体显像中，特异性ＩＢＺＭ的结合和其他半定量参数的计算，最好选用额叶皮质作为非特异性结合参照区。
Objective To investigate the non-specific uptake of striatum in brain dopamine receptor imaging. Methods The data of rat in vivo were used to compare striatum with 125I (s) (-) 3iod 2hydroxyl obtained by comparing the frontal cortex and cerebellum as nonspecific uptake of striatum. 6 methoxy N ((1 ethyl) 2 pyrrolidinyl) methyl] benzamide (IBZM) results. Results Iodine-labeled IBZM displayed a stereoselective and reversible binding to the striatum dopamine D2 receptor. Frontal cortex and cerebellum show rapid uptake and elution of ligands. Saturation of IBZM was not achieved when cerebellar uptake was used as a reference for non-specific uptake of the striatum, whereas saturability was demonstrated with the frontal cortex as a reference area with Bmax = 44 pmol / g of striatum. Percentage differences in the rate of substitution of Haloperidol and striatum and other brain regions derived from high-dose spiperone or haloperidol competitive inhibition experiments suggest that cerebellar uptake underestimates the nonspecific uptake of the striatum, the frontal cortex Is a suitable non-specific uptake of striatal reference area. Conclusions In the calculation of specific IBZM binding and other semiquantitative parameters in striatal dopamine D2 receptor imaging, it is best to use the frontal cortex as the non-specific binding reference region.